Top 200 Programs/Top 200 Programs.iso/Bob8/TESTWARE/GEOCLOCK/PRODUCT/GEOCLOCK.DOC

Text File | 1996-02-29 | 170KB | 3,773 lines

GEOCLOCK (TM) 7.2, 96/03/01,(C) 1996 Joseph R Ahlgren, BBS 703-241-7980

Help Master Menu

Use the up and down arrow keys or mouse to select the topic of interest.
Pressing ENTER or clicking the left button will display a menu of detailed
topics, while pressing ESCAPE or the right button will return to GeoClock.
If you are new to GeoClock, you should read the "Getting Started" section.
As you become familiar with the program, you should browse through the
other topics to learn about the GeoClock options and features.

 1.  Getting Started
 1.1  GeoClock Files
 1.2  Initial Setup
 1.3  Running GeoClock in Windows 3.x
 1.4  Configuring for SVGA Graphics
 1.5  Mouse
 1.6  Editing ASCII Files with the TED Editor
 1.7  Common Problems
 2.  Running GeoClock
 2.1  Getting Help
 2.2  Selecting A Map
 2.3  Measuring Distance
 2.4  City/Country Names
 2.5  Latitude/Longitude Lines
 2.6  Time
 2.7  Options
 2.8  Where
 2.9  GeoGlobe
 2.10 Quitting
 3.  About...
 3.1  About GeoClock
 3.2  About Time Zones
 3.3  About Sunrise and Sunset
 3.4  About the Terminator
 3.5  About Latitude and Longitude
 4.  Commands
 4.1  Command Summary
 4.2  Icon/Mouse Controlled Commands
 4.3  Help Control
 4.4  Map Selection
 4.5  Map Annotation
 4.6  Time Control and Display
 4.7  Map Display
 4.8  Sun and Moon Display Control
 4.9  Time, Zone and Format Control
 4.10 Special Commands
 4.11 Mouse, Graphics, and Color Control
 4.12 Zoom
 4.13 Distance Measurement
 4.14 Scripts
 5.  Advanced Topics
 5.1  Configuring for Your Time Zone
 5.2  City Locations on Maps
 5.3  Configuring for Your City
 5.4  Finding Your Latitude and Longitude
 5.5  City Name Placement and Time Display
 5.6  Make Zoom utility
 5.7  Colors and Default Colors
 5.8  Changing GeoClock Defaults
 5.9  Calendars and Daylight Saving Time
 5.10 Ephemeris Data and Accuracy
 5.11 Software structure
 5.12 Map Generation System
 5.13 Elevation Maps
 6.  Utilities and GeoGlobe
 6.1  GeoGlobe     Spinning Globe program
 6.2  GeoSetup     Customize GeoClock
 6.3  MakeZoom     Rebuild zoom tables
 6.4  XXGeoDat     Delete unnecessary GEOn.DAT files
 6.5  GeoNoDup     Delete unnecessary MAPn.EGA files
 6.6  SunData
 7.  HAM package
 7.1  HAM package features
 7.2  Starting the HAM package
 7.3  HAM CD-ROM
 7.4  Call Sign Analysis
 7.5  Use of other GeoClock features
 7.6  Twilight zone definition
 7.7  HAM data base
 7.8  Support
 7.9  Call Sign Analysis Algorithm
 8.  Registering/Updates
 8.1  Updates
 8.2  Available Maps
 8.3  About the GeoClock Bulletin Board
 8.4  GeoClock 7.1 special pricing
 8.5  Ordering GeoClock 7.1



 1.  Getting Started

Use the up and down arrow keys to select the topic of interest.  Pressing
ENTER will display information about that topic.  Press ESCAPE to return to
the main help menu.  If you are new to GeoClock, you should read all the
topics listed here.

 1.  Getting Started
 1.1  GeoClock Files
 1.2  Initial Setup
 1.3  Running GeoClock in Windows 3.x
 1.4  Configuring for SVGA Graphics
 1.5  Mouse
 1.6  Editing ASCII Files with the TED Editor
 1.7  Common Problems



 1.1  GeoClock Files

  The following describes and identifies the files associated with
GeoClock.

  GEOCLK71.LZH (or ZIP) contains the DOS version of GeoClock, this help
file, a set-up program, and several utility programs and data files to help
you get started in customizing the program.

README.1ST        Special information - read this first
GEOCLK.COM        GeoClock/GeoGlobe master program
GEOCLK.EXE        GeoClock DOS program for EGA/VGA/SVGA
GEOCLOCK.HLP      Help files text
GECONFIG.DAT      Text file with configuration data
GEOZONES.DAT      Text file with time zone data
GEOCLOCK.DAT      Text file with default map overlay data
GEOCLOCK.ICO      Win 3.x icon for GeoClock
TED.COM           Text editor program
VGATOEGA.EXE      Program to convert VGA maps to EGA
GEOSETUP.EXE      Program to help set up GeoClock
USCITY.BIN        Data base of US cities
WRLDCITY.BIN      Data base of World cities
MAKEZOOM.EXE      Program to make the zoom hierarchy
GEOSCR9.DAT       "Screen Saver" script
MAILER            Order form
MAP1.EGA          Map of the world
MAP2.EGA          Map of the 48 states
MAP2000.EGA       North polar projection map
MAP2501.EGA       View from space (orthographic projection) map
GEO1.DAT          City file for MAP1
GEO2.DAT          City file for MAP2
GEO2000.DAT       City file for MAP2000
GEO2501.DAT       City file for MAP2501
WHATSNEW.71       Short description of new features in 7.1
FILE_ID.DIZ       Shareware file description
VENDOR.DOC        Shareware vendor requirements

There is an optional GEOXTR71.LZH (or ZIP) file which contains some extra
files.  The files have not changed since GeoClock 6.0 was released:

MAP3.EGA          Map of North America
MAP4.EGA          Map of South Pacific
MAP5.EGA          Map of Europe
GEO3.DAT          City file for MAP3
GEO4.DAT          City file for MAP4
GEO5.DAT          City file for MAP5
ZIPCODES.BIN      US zip code lookup for GEOSETUP
XXGEODAT.EXE      Program to delete unneeded GEOn.DAT files
GEONODUP.EXE      Program to delete unneeded MAPn.EGA files
SUNDATA.EXE       Program to produce tables of sun rise/set and twilight
FILE_ID.DIZ       Shareware file description
VENDOR.DOC        Shareware vendor requirements

The Windows version of GeoClock is in GCKWIN71.LZH (or ZIP) and contains:

README.1ST        Special information - read this first
GEOCKWIN.EXE      GeoClock Windows program
GEOCKWIN.HLP      Help files text
GECONFIG.DAT      Text file with configuration data
GEOZONES.DAT      Text file with time zone data
GEOCLOCK.DAT      Text file with default map overlay data
USCITY.BIN        Data base of US cities
WRLDCITY.BIN      Data base of World cities
GEOSCR9.DAT       "Screen Saver" script
MAILER            Order form
MAP1.EGA          Map of the world
MAP2.EGA          Map of the 48 states
MAP2000.EGA       North polar projection map
MAP2501.EGA       View from space (orthographic projection) map
GEO1.DAT          City file for MAP1
GEO2.DAT          City file for MAP2
GEO2000.DAT       City file for MAP2000
GEO2501.DAT       City file for MAP2501
WHATSNEW.71       Short description of new features in 7.1
FILE_ID.DIZ       Shareware file description
VENDOR.DOC        Shareware vendor requirements


  The registered version of GeoClock includes these files, plus many map
files, customization files for each map, and some utility programs.

Several types of data files are used while GeoClock is running:
GECONFIG.DAT
  This text file contains the data to configure GeoClock for your system.
  It has information about your graphics system, your local time zone and
  location, and any commands you want to establish as defaults.
GEOCLOCK.DAT
  This text file contains the default overlay data for all GeoClock maps.
  The first line in this file gives the local time zone.  The second line
  gives the latitude, longitude, and city name for the primary city (i.e.,
  the city listed in the map legend).  Subsequent lines give the names and
  locations of other cities to be displayed.
GEO*.DAT
  * is any integer. These text files contain similar data to GEOCLOCK.DAT,
  including a primary city for the map, but the data apply only to MAP*.
  For example, GEO3.DAT contains the data for MAP3.  If a map has no
  corresponding GEO*.DAT file, cities and other data in GEOCLOCK.DAT are
  used instead.  These files can also contain other commands for display
  on the indicated map.
MAPn.EGA
  These binary files contain the maps.  The extension (.EGA) is the file
  format, and is used for EGA, VGA, and SVGA maps.  By convention, map
  numbers (n) have the following designations:
        1 -   99   640x480 (VGA) resolution world and regional maps
      100 -  299   North America detailed maps
      300 -  399   Central/South America detailed maps
      400 -  599   Europe detailed maps
      600 -  699   Asia detailed maps
      700 -  799   Middle East detailed maps
      800 -  899   Africa detailed maps
      900 -  999   Pacific detailed maps
     1000 - 1999   Other VGA resolution maps
     2000 - 2499   Polar or other large area non-rectangular projection
     2500 - 2999   Orthographic (View from Space) projection
     3000 - 3999   Small area (city) maps
     4000 - 5999   640x480 (VGA) resolution special maps
     6000 - 6999   800x600 (SVGA) resolution maps
     7000 - 7999   350x640 (EGA) resolution maps
     9000 - 9999   Azimuthal-equidistant (great circle) projection
GEOZONES.DAT
  This file contains all the time zone definitions (ZONE commands) in text
form.
GEOZONES.BIN
  This file is a processed version of GEOZONES.DAT and speeds the start-up
of the GeoClock program.
GEOINDEX.BIN
  This file contains the map directory used for the map selection (S) and
Zoom (Z) functions.  It is built automatically by GeoClock, and is
automatically updated each time you add or delete a map.
GEOZOOMU.TXT
  This text file contains the zoom-out hierarchy for the maps.  For each
map, the file gives the map to zoom-out to.  The file is produced by the
MAKEZOOM program, but can be edited by any ASCII text editor, including
TED, to change the hierarchy.
GEOZOOMU.BIN
  This binary file contains the zoom-out hierarchy in the format used by
GeoClock.  It is produced by MAKEZOOM from GEOZOOMU.TXT.
GEOSCRn.DAT
  These files contain scripts, which are activated by pressing the
corresponding key (for example, 9 to start GEOSCR9.DAT).
USCITY.BIN, WRLDCITY.BIN, ZIPCODES.BIN
  These files contain the data bases used by GEOSETUP and by the Where
function in GeoClock.







 1.2  Initial Setup

  GeoClock requires a hard disk, a minimum of 300K available RAM (up to
350K to use the HAM package), and a graphics adapter and monitor.

   GeoClock is contained in GEOCLK71.LZH and is designed to support
computers with a 256K EGA, VGA, or SVGA boards with a compatible color
monitor.  To get the program running, do the following:
  1.  Un-LZH GEOCLK71.LZH (by typing LHA e GEOCLK71) to the directory you
will run from.  It is best to have a directory dedicated to GeoClock.  If
you have special map files, also un-LZH all these (by typing LHA e
GEOMAP*).
  2.  Customize GeoClock for your location and time zone.  Run the
GEOSETUP program (see below), or follow the directions in "Configuring for
Your Time Zone" and "Configuring for Your City."
  3.  If you are a registered user, you need to run the REGISTER program
to enable the special features.  This is run automatically by GEOSETUP.
  4.  Run the MAKEZOOM program.  This is run automatically by GEOSETUP.
  5.  Run GeoClock by entering GEOCLK on the DOS command line.  The F1 key
provides help, and the Q key (Quit) terminates the program.  If you have a
VGA or better, the mouse is always active, and the Icon Bar at the top of
the screen allows you to click on several common GeoClock commands to
immediately explore the capabilities of the program.  Alternatively,
pressing the highlighted letter gives access to the command.

Running GEOSETUP
   The GEOSETUP program performs all the necessary initial customization of
GeoClock for your location.  It sets up time zone and primary city data,
and sets GeoClock for EGA, VGA, or SVGA operation.  Start GEOSETUP by
typing GEOSETUP at the DOS command line.
   GEOSETUP tries to detect the type of video card you have.  If you have a
VESA compliant SVGA (800x600x16), GEOSETUP will optionally test the card by
producing a 800x600x16 display.  If the display is correct, GEOSETUP will
customize GeoClock for SVGA display.
   If you have a US zip code (other than APO or FPO addresses) and the
ZIPCODES.BIN file, GEOSETUP will automatically supply the proper time zone
and latitude/longitude information.  All you need to do is enter your zip
code and city name when prompted.  If you do not have a US zip code, you
can select a city from the list displayed.  Pressing a letter key will
advance the cursor to the countries starting with that letter, the PageUp
and PageDown keys move to the next country, and the arrow keys allow you to
move through the list one at a time.  Press ENTER when you have found your
city, or a city close to your city.  In either case, you must specify
whether you have an EGA or VGA or SVGA based display.  With this
information, GEOSETUP builds an initial GECONFIG.DAT.







 1.3  Running GeoClock in Windows 3.x


The windows version of GeoClock (GEOCKWIN.EXE) is functionally and
graphically vert similar to GeoClock for DOS, but runs in windows in the 16
bit windows mode.  It supports windows style multitasking, will run in an
arbitrarily sized window, and in the foreground and background.

The DOS version of GeoClock runs well under windows 3.1 and is
significantly faster than the windows version, but as with any DOS graphics
program, there are a few limitations.  Most important, GeoClock will only
run in the full screen mode, and all other windows applications will be
suspended while GeoClock is running.  You can switch to another window by
pressing ALT-Escape, or by quitting GeoClock.

The GEOCLOCK.ICO file is a windows icon that can be used with GeoClock.

After GeoClock is installed, you can add GeoClock to a windows group by
following these steps:

1.  Select group you want GeoClock in (single click any icon in the group)
2.  Click File on Program Manager
3.  Click New...
4.  Click Program Item
5.  Click OK
6.  Type Program Description (GeoClock)
7.  Click Command Line
8.  Type c:\geoclock\geoclk.com (or whatever the correct path/program are)
9.  Click Working Directory
10. Type c:\geoclock (or whatever the correct path is)
11. Click Change Icon (if you get the "no icons" message, click OK")
12. Click Browse
13. Select the drive and directory where GeoClock was installed
14. Double click GEOCLOCK.ICO
15. Click OK
16. Click OK

GeoClock can then be run by clicking the GeoClock icon.







 1.4  Configuring for SVGA Graphics

   GeoClock can display maps in the 800x600x16 SVGA format.  Unfortunately,
each manufacturer of video cards has chosen a different way to enter this
graphics mode.  Worse, as new cards are introduced, these codes change. If
you have an SVGA and want to use the 800x600x16 mode with GeoClock, you
must add the appropriate SVGA command for your graphics adapter to your
GECONFIG.DAT file.  Most new graphics boards support the VESA standard
(although some require a special driver).  The GEOSETUP program
automatically test for a VESA compliant SVGA card.  SVGA with no parameters
uses the VESA standard.  Some other codes that have been verified are:

SVGA            VESA standard

SVGA24          Tecmar VGA/AD
SVGA31          Realtek
SVGA41          VEGA VGA,Orchid,STB,Genoa,Sigma,Allstar Peacock (VGA)
SVGA41          Tseng ET4000 chipset,definicon,Diamond
SVGA71          AT&T VDC600
SVGA82          Oak
SVGA84          ATI
SVGA88          Paradise VGA,AT&T VDC600,AST VGA Plus, Western Digital,
SVGA88          Compaq VGA,Dell VGA,Hewlett-Packard D1180A,NCR
SVGA91          Maxxon, SEFCO TVGA, Imtec, Trident TVGA 8800/8900, Phoebes
SVGA94          Logix, ATI Prism Elite
SVGA98          VEGA VGA,Tatung VGA,Video7 V-RAM VGA
SVGA100         Morse VGA
SVGA106         Ahead A, Ahead B, Genoa 6400, Hi Res 512
SVGA106         Zymos Poach, Epson LT-386SX,CompuAdd 316SL, ATI VGA Wonder
SVGA112         Cardinal, C&T chipset
SVGA112/2       Everex
SVGA113         NSI Smart EGA+
SVGA121         Quadram Ultra VGA
SVGA20226/258   VESA SVGA BIOS
SVGA20226/514   S3 based windows cards, Orchid 1280

You can use any ASCII text editor to edit the GECONFIG.DAT file, such as
EDIT included with DOS 5.0+, or TED, which is included with GeoClock (see
section 1.6).  Add the appropriate command to the end of the GECONFIG.DAT
file.

Unfortunately, there is no consistency between manufacturers and even
between models of a given manufacturer for the operation of SVGA modes.
Above is a list of some of the manufacturers and codes.  You can use the
VESA code if you have a VESA driver for your video card.  In particular,
the ATI Graphics Ultra card requires an ATI supplied VESA driver.  If your
adapter is not listed, check with your board supplier or user's manual. The
syntax is SVGAa/b/c/d, where a, b, c, and d are the decimal vales of the
AX, BX, CX, and DX registers to enter the 800x600x16 graphics mode by
executing INT 10.







 1.5  Mouse

     Certain GeoClock functions can be controlled by a mouse.  In
particular, Zoom, Distance Measurement, Lat/Long Toggle, City/Country
toggle, Speed, Time, Help, and Quit can all be controlled with a mouse.  In
addition, execution of the zoom and distance functions use the mouse.
     GeoClock is designed so that the mouse is always active when the
program is initially activated.   The most common GeoClock commands have
been included in an Icon Bar, and selections are made with the mouse
buttons.  Several mouse commands are also available (and described later in
this help) to modify availability/visibility of the Icon Bar for individual
users.  However, you may move the mouse-controlled cursor off the screen,
or press the ALT key, to remove the Icon Bar at any time desired.
     To use your mouse device with GeoClock, the INT 33 driver must be
loaded.  This driver, which comes with most mice, is usually called
MOUSE.COM or MOUSE.SYS.  You need this driver even if you are running under
windows and the windows mouse driver is loaded.  It is likely that it is
already installed if you have been using your mouse with other computer
programs.  Also, except for special versions of the Distance and Zoom
functions, the mouse can only be used on a VGA or better display.  It will
not work well with an EGA display because of its hardware characteristics.

     Two special function, the Distance function activated by the @ key,
and the Zoom function activated by the Z key (available only to registered
users) use a graphics cursor which can be operated either from the keyboard
or by a mouse.  The mouse buttons and functions match the keyboard as
follows:

    Left Mouse Button           Control (CTRL) and Page-Up keys
    Center Mouse Button         Escape (ESC) Key and Enter
       (if available)
    Right Mouse Button          Alternate (ALT) and Page-Down keys
    Mouse Motion                Arrow and Shift-Arrow keys

     All the keyboard functions work, even if a mouse is activated.  For
example,  the arrow keys may be used to "fine-tune" the cursor position
after the mouse has moved the cursor to the vicinity of the desired point.
The Escape or Enter key is used if your mouse does not have a center
button.







 1.6  Editing ASCII Files with the TED Editor

     Some customizing GeoClock may require editing the various GEO*.DAT
files.  Any ASCII text editor can be used.  If you use a word processor to
edit the files, be sure to save the files in ASCII (DOS text) format rather
than the word processor's format.
     The public domain editor TED (Tiny EDitor) is supplied with GeoClock.
It is a simple text editor, perfect for customizing these text files.  To
edit a file (for example, GEOCLOCK.DAT), enter TED <file name> at the DOS
prompt.  For example:
TED GEOCLOCK.DAT
The file will appear on the screen, with a function key reminder block at
the bottom.  The arrow and other cursor positioning keys can be used to
move the cursor around the file.  The delete, insert, and other keys can be
used to change the text in the file.  Five function keys are especially
handy:
F1    ABORT      Exit editor without saving changes
F7    EXIT       Exit editor and save changes in ASCII format
F8    DEL EOL    Delete from cursor to end of line
F9    DEL L      Delete line
F10   UDEL L     Undelete line







 1.7  Common Problems

1 The sun is not in the right place.
  This is usually caused by your PC's system clock not being set to the
  correct time, or a wrong or missing PCZONE command in the GECONFIG.DAT
  file.  Run GEOSETUP to quickly configure GeoClock for your home town and
  time zone.  Alternatively, see "Configuring for Your Time Zone."
  GeoClock is initially set to assume your PC is in Eastern US time.

2 Your home town or your local time zone is not displayed.
  The world and U.S. maps in GeoClock (Maps 1 and 2) are initially
  configured for Eastern Time and Washington DC.  Run the GEOSETUP to
  quickly configure GeoClock for your home town and time zone.
  Alternatively, you can customize each map.  The first line of every
  GEO*.DAT file gives the time zone to display.  The second line of each
  GEO*.DAT file gives the latitude, longitude, and city name to be
  displayed at the bottom of the screen.  Use an ASCII text editor to
  change the GEO*.DAT files for your situation.  See "Configuring for Your
  City" and "City Locations on Maps."

3  Your hometown is not displayed in the right place.
  The most likely problems is that the coordinates you used are not
  accurate.   The coordinates that GEOSETUP produces from zip code data
  are not always accurate, especially in sparsely populated areas.  You
  might get better coordinates from your local airport, weather service, a
  good atlas, or call the GeoClock BBS.  Also be sure that you have the
  correct direction for the coordinates (most locations in the US are
  North (+) Latitude and West (-) Longitude).

4 The screen blinks.
  This is a problem on some EGA and VGA boards with the Trident chip set.
  Add the FLICKER and/or NOBLINK commands to the GECONFIG.DAT file.

5 The program does not work on a CGA or Hercules systems.
  That is correct.  The capability of these modes is too limited for
  GeoClock.

6 The maps and other data are hard to see on a grey scale or LCD VGA
  system.
  GeoClock is configured to look best on a full color VGA or EGA. If you
  answer the "Do you have a color display" question from the GEOSETUP
  program 'NO", it adds the following color commands to give good grey
  scale appearance:
  COLOR00307
  COLOR10902
  COLOR20228
  COLOR31806
  These may not the best for your particular system.  Use the CSET command
  described in section 4 to experiment to find the best values for your
  system, then change the lines in GECONFIG.DAT to the selected values.

7 The program always starts with the help menu.
  This menu is bypassed only on registered copies of the program.  If you
  have registered a previous version, you need to re-run the REGISTER.EXE
  program supplied on the original distribution disks (and probably on
  your hard disk) to register the updated version.

8 The Icon Bar does not appear.
  You have moved the mouse controlled cursor off of the screen, or pressed
  the ALT key.  Press ALT again, or move the mouse back on screen.  If you
  have an EGA system, the mouse cursor will not appear and the Icon Bar is
  controlled by the ALT key only.  Also, see the MOUSEX command (4.11)

9 The mouse does not work.
  You have an EGA system, or you have not installed the DOS mouse driver
  (INT 33 driver) that should have come with your mouse.

10 Zoom does not work right.
  The zoom data file may be out of date.  Rerun the MAKEZOOM program.

11 The BuckMaster CDROM does not work with GeoClock.
  Starting with the October 1995 release, BuckMaster has dropped the file
  (HAMCALL.129) that GeoClock uses, and will not release the format of the
  replacement file.  GeoClock does support the QRZ CDROM.







 2.  Running GeoClock

These topics give you a quick overview of how to run and control GeoClock.
More detailed explanations of these features, and details of more advanced
features, are in the other sections of this help system.

 2.  Running GeoClock
 2.1  Getting Help
 2.2  Selecting A Map
 2.3  Measuring Distance
 2.4  City/Country Names
 2.5  Latitude/Longitude Lines
 2.6  Time
 2.7  Options
 2.8  Where
 2.9  GeoGlobe
 2.10 Quitting



 2.1  Getting Help


Clicking the HELP icon, or pressing the "?" or F1 key, brings up this help
system.  You can navigate through the help system using the cursor keys or
a mouse.  You can print help by pressing ALT-P and answering the questions.
You can "C"hange the print to print to a file or to control the pagination.

If you use "C" to specify a file for printing, subsequent sections will
also be printed to the file by default.

You can contact GeoClock for technical help:
BBS  703-241-7980  (v.32bis, N81)
FAX  [phone]
CompuServe  70461,2340  (Joe Ahlgren)
Internet  [e-mail]







 2.2  Selecting A Map


There are several ways to change the map being displayed.

If you move the mouse cursor over a point on the map, and click the left
mouse button, the most detailed map containing that point will be displayed
(zoom-in).  Clicking the right button zooms out through successively less
detailed maps.

Clicking the MAPLIST icon, or pressing the "M" key, brings up a list of all
available maps.  You can pick a map by using the cursor keys and pressing
enter, or by clicking the map name directly with the mouse.

Pressing the "F" key brings up a list similar to "M", but provides more
detailed information about each map.

Pressing "K" displays the penultimate map.  You can use this to repeatedly
toggle between two maps.

The "+" and "-" keys move one map forward or backwards in the current sort
order (the sort order from the MAPLIST function).







 2.3  Measuring Distance


Clicking on this icon, or pressing D, starts a special two point distance
measuring function.  One point is fixed and the other is controlled by the
mouse.  Pressing a mouse button, or pressing ENTER, moves the first point
to the current mouse position.  At the bottom of the screen, the
coordinates of both points, the distance between them, and the azimuths
between them are displayed.  To exit the distance function, click the reset
icon in the upper right, or press ESCAPE.  In this function, if you do not
have a physical mouse and a VGA or better, the cursor can be moved with the
arrow keys, and shift-arrow will move the cursor 8 times faster than arrow.

In this function, the cursor can be moved with the arrow keys.  Shift-arrow
will move the cursor 8 times faster than the arrow keys alone.  If you do
not have a physical mouse and a VGA or better, this is the only way to move
the cursor.







 2.4  City/Country Names


Clicking on this icon, or pressing Y, toggles between display of city names
("city") and names of countries, states, and other geographic features
("country").







 2.5  Latitude/Longitude Lines


Clicking on this icons alternately displays and hides latitude and
longitudes lines.  It is equivalent to the GRID and NOGRID commands.







 2.6  Time


When properly set up by running the GEOSETUP program, GeoClock converts
your current local time to the various times around the world.  There are
several ways to vary the displayed time.

By clicking the SetTime icon, or pressing the "T" key, you can enter a new
time.  This display will correspond to this new time, but your system clock
will not be changed.

By clicking the Speed icon, or pressing the "S" key, you can change the
rate of time passage.  For example, by entering 1 at the rate prompt, the
displayed time will change by one hour every time the screen is updated.
This shows very quickly how the sunlight changes over time.  If you set the
rate to 24 or 48 hours, for example, you can see how the sunlight curve
changes over the seasons.

Clicking the Reset icon, or pressing the "R" key, will set both the time
and the rate back to the real time.  Note that the RESET icon only appears
when the time or rate has been changed.







 2.7  Options


Clicking to Options icon, or pressing the letter "O", allows you to change
some of the basic display parameters for GeoClock.  Repeat clicking (or
pressing right or left arrow or tab) a selected item cycles the item though
its possible values.  Clicking an unselected item, or using the up and down
arrows, selects a new item.  Pressing "Escape" quits without making any
changes, while pressing "Enter" applies the changes to the current map
being display, and makes the new values the default values until GeoClock
is exited.

Pressing Function Key 3 makes the current values the permanent default
values, which will be used every time GeoClock starts.  Pressing Function
Key 4 makes the current values the permanent values for the map currently
displayed.







 2.8  Where


Clicking the Where icon, or pressing the letter W, starts GeoClock
gazetteer.  This system can locate any of the approximately 4000 cities
included in the GeoSetup program.  Pressing or clicking a letter moves the
display to the state/country starting with that letter.  The cursor control
keys can be used to navigate through the city list.  Tab, or clicking the
appropriate data base name, will shift between US cities and world cities.
Local time for the highlighted city is displayed.  Clicking a city, or
pressing enter, will return to the map display, with the selected city
highlighted with time and ephemeris data.  The map displayed is the highest
resolution map showing the city.  Pressing "R" or clicking reset returns
the map to the original city.







 2.9  GeoGlobe


If you have the GeoGlobe program and start GeoClock using GEOCLK.COM (this
the default start program), clicking this icon will start GeoGlobe.  When
GeoGlobe is terminated, GeoClock will restart.  You can pass parameters to
the GeoGlobe program with the WCGLOBE command.

The GeoGlobe icon appears only if the GeoGlobe program is named
GEOGLOBE.EXE, is in the same directory as GeoClock, and GeoClock was
started with GEOCLK.COM rather than GEOCLK.EXE.







 2.10 Quitting


Clicking the DOS icon terminates the program and returns to DOS.  You can
also quit the program by pressing the Q key, or quickly pressing the escape
key twice.







 3.  About...

These topics provide information about GeoClock and the astronomical and
geographical "facts of life."

 3.  About...
 3.1  About GeoClock
 3.2  About Time Zones
 3.3  About Sunrise and Sunset
 3.4  About the Terminator
 3.5  About Latitude and Longitude



 3.1  About GeoClock

     "It's inconceivable that you won't like this program."  -- Jerry
Pournelle, BYTE

     GeoClock shows the current time (based on your computer's clock) with
a high quality map of the earth.  The current sun position is displayed,
and the parts of the earth in sunlight and twilight are highlighted.  This
display is automatically updated every few seconds.  Local sunrise, sunset,
the sun's azimuth and elevation, and times around the world are also
displayed.  A variety of map backgrounds and other options are available. A
graphics adapter and a hard disk are required.  GeoClock is an EGA-VGA-SVGA
program operating in the 16 color mode.
      GeoClock is distributed as shareware.  This means that if you use and
enjoy the program, you are expected to register it.  See "Ordering
GeoClock" for details.  The registered version includes the zoom, distance
measuring, and city time display functions, and at least 40 maps.

GeoClock    Joseph R Ahlgren    2218 N Tuckahoe St    Arlington VA 22205
          CompuServe 70461,2340 (Joe Ahlgren)
          Voice 703-241-2661         BBS 703-241-7980    FAX [phone]







 3.2  About Time Zones

     Time zones are more complicated than most people think.  To begin
with, they change with longitude, so that the sun is approximately overhead
at noon.  However, various political decisions based on uniformity, local
custom, and how to handle daylight saving time (or summer time), have made
time zones very complex.  There are a number of changes every year, and
countries can change their time systems without warning.
     Data for all known time zones (about 100, including permutations of
daylight saving time) are distributed with GeoClock.  They are included in
the GEOZONES.DAT file.
     To specify a time zone, several items are needed.  First, how the time
zone relates to the standard time zone must be defined.  This zone is
variously called Greenwich Mean Time (GMT) or Universal Time Coordinated
(UTC) or Zulu Time (Z).  US Eastern Standard Time is five hours behind
(earlier than) GMT.  Next, the dates and times when the zone changes to and
from summer time must be defined.  US Eastern Time goes to summer time on
April 7, 1991 at 0700 GMT, and returns to standard time on October 27, 1991
at 0700 GMT.  Finally, names for the time zone and the standard and summer
times must be specified.  As an example, US Eastern Time from April 1991 to
April 1992 is specified by:

ZONE   ET     EST     -5     EDT     -4     91/04/07:7   91/10/27:7

ET is the name the time zone is referred to by all GeoClock commands.  The
definition states that the zone is called EST and is 5 hours behind GMT,
except between 91/04/07 0700 GMT and 91/10/27 0700 GMT, when it is called
EDT and is 4 hours behind GMT.  A special time zone called ST gives true
local sun time.
     If the ZONE commands are not for the correct year, GeoClock will
automatically update.  This update is close but not always correct, and
countries' summer time definitions can change.  Therefore, I recommend that
the ZONE commands be kept current. A GEOZONES.DAT file with current time
zone data is available on the GeoClock Bulletin Board.
     The PCZONE command sets the relationship between the local time on the
PC's clock and GMT, i.e., declares which time zone the PC's clock is in. It
takes one parameter - a time zone code, as defined in the ZONE command. For
example, if you use Eastern Time, specify:
PCZONE ET
This command is best used in the GECONFIG.DAT file.








 3.3  About Sunrise and Sunset

     GeoClock calculates the sunrise and sunset times for your location.
The times are usually within one minute of local newspaper data.
     The precise moment of sunrise or sunset is difficult to determine.  It
depends not only on the position of the Earth and sun, but also on the
terrain near you (it appears to rise later from behind a mountain than from
the sea), and on the earth's atmosphere.  Another complication is that the
sun appears quite large, and takes about two minutes to shift position by
its own diameter.  All these factors together mean that even at sea level,
the sun appears to just break above the horizon when it is in reality
almost one degree BELOW the horizon.
     By default, GeoClock uses the value of 0.833 degrees below the horizon
to compute sunrise and sunset.  This agrees well with observed times at
moderate latitudes and flat terrain.  The SUNANGLE parameter, which is the
angle GeoClock uses for the sunrise and sunset calculations, can be
adjusted to correspond to your local conditions.







 3.4  About the Terminator

     The terminator is the boundary between day and night.  Its position
changes during the day (it makes a complete circuit around the Earth in one
day), and it also changes during the year.  Daylight is longer in the
northern hemisphere than in the southern hemisphere from about March 21 to
September 21, and daylight is longer in the southern than in the northern
hemisphere during the rest of the year.  You can see the changes by using
the time control features of GeoClock.
     The terminator more or less divides the Earth into halves: facing the
sun and facing away from the sun.  Like sunrise and sunset times, the pre-
cise location of the terminator is hard to define.  By default, GeoClock
shows the optical terminator, which corresponds to visual sunrise and
sunset.  The SUNLIGHT command can be used to control the precise terminator
position.  If it is set to the same value as SUNANGLE, the terminator
position will agree with sunrise and sunset.
     GeoClock also shows the twilight terminator.  By default, GeoClock
uses -6°, which corresponds to the civil definition of twilight: the time
when it is so dark that you must use your headlights.  The TWILIGHT
parameter is used to control the precise definition of this terminator.







 3.5  About Latitude and Longitude

     Every point on the Earth's surface has an address.  The first part of
the address is the latitude, which is the distance north or south of the
equator.  The second part of the address is the longitude, which is the
distance east or west of a line going from the north pole to the south pole
through Greenwich, England (this is called the Greenwich meridian). Since
the Earth is a sphere, these distances are expressed as angles.
     There are several ways to express these angles. The first system was
invented by the Babylonians about 5000 years ago.  It divides angles into
360 degrees (°), each degree into 60 minutes ('), and each minute into 60
seconds (").  The Washington Monument is 38° 53' 21.5" north of the
equator, and 77° 2' 8.0" west of the Greenwich meridian in this system.
This location is accurate to about 60 feet, or 0.5 seconds. GeoClock can
use this system.  For example, the Washington Monument is at
38x53x21.5N  77x2x8.0W
     A more modern system gives these same angles as decimal degrees. North
latitudes and east longitudes are positive, while south and west are
negative.  GeoClock can use this system also.  It is used for data files
distributed with GeoClock.  For example, the Washington Monument is at
+38.8893  -77.0356







 4.  Commands

GeoClock has a variety of commands, keys, and icons to control the display.

 4.  Commands
 4.1  Command Summary
 4.2  Icon/Mouse Controlled Commands
 4.3  Help Control
 4.4  Map Selection
 4.5  Map Annotation
 4.6  Time Control and Display
 4.7  Map Display
 4.8  Sun and Moon Display Control
 4.9  Time, Zone and Format Control
 4.10 Special Commands
 4.11 Mouse, Graphics, and Color Control
 4.12 Zoom
 4.13 Distance Measurement
 4.14 Scripts



 4.1  Command Summary

    GeoClock has a large number of commands which may be used to control
the display.  The most commonly used commands have been implemented in an
Icon Bar, which is displayed at the top of the screen.  A mouse device may
be used to activate any of these commands simply by moving the mouse
controlled cursor to the appropriate icon and clicking on it with the left
mouse key.  The commands consisting of a single letter (such as S) are
activated by pressing that letter.  The other commands (such as MAP) may be
included in the configuration file, in a data file, on the GeoClock command
line, or entered interactively by pressing the C (for Command) key while
GeoClock is displaying a map.
    The available commands are listed below. More detailed information is
available in other sections of Help.  Each group of commands listed below
is described in a separate section of this part of Help.

*** Icon/Mouse Controlled Commands
Quit           Quit to DOS
Reset          Reset time and speed
Help           On line help
Set            Set time
Speed          Set speed to time passage
Country/City   Toggle between city and country display
Lat-Long       Toggle latitude/longitude lines
Distance       Measure Distances
Maplist        Select a map from a list
Zoom           Zoom in (left button) or zoom out (right button)
Globe          Start the GeoGlobe program (if available)
*** Help Control
HELP (or H)  Activates Help system
?            Activates Help system
F1           Function Key 1 - Activates Help system
REM          Remark - remainder of line is ignored
*** Map Selection
M            select a map from compact list
F            Find map in list
MAP          Find map in list
MAPn         Changes to map number n
MAPPLUSn     Selects the next sequential map using sort method n
MAPMINUSn    Selects the previous sequential map using sort method n
RANDOM       Picks a map at random to display
NOMAP        No map displayed
MAPCENTERn   Center world map on longitude n
*** Map Annotation
FULL         City, sun rise/set, local time, sun position legend
NONE         No legend
TIME         Local time only legend
SUN          City, sun rise/set, local time legend
DATECHANGEn  Control display of next/previous date
HTA          Display specified city as primary city on all maps
HTS          Display specified city as primary city on maps it appears
HTN          Do not display specified city as primary city
NOHT         Same as HTN
MARKLIMIT    Control display of cities close to HTA/HTS city
HIDEMN       Do not display map name and number
SHOWMN       Display map name and number
POSMN        Set position and color of map name and number
TEXT         Display text on all maps
NAUTICAL     Display distances in nautical miles
STATUTE      Display distances in statute miles
*** Time Control and Display
YEAR2        Show 2 digit year (e.g., 91)
YEAR4        Show 4 digit year (e.g., 1991)
NOMONTH      Show month number
SHOWMONTH    Show month name
NODAY        Do not show day of week
SHOWDAY      Show day of week
NOSECONDS    Show time to last minute
SHOWSECONDS  Show time to nearest second
DST          Control Daylight Saving Time
ZONE         Define time zone
PCZONE       Specify PC time zone
*** Map Display
DATAFILE     Select extension for data files
COUNTRY      Display country names
NOMARK       Do not display location markers
MARK         Display location markers
FORCEMARK    Always display location markers
NOCITY       Do not display city names
CITY         Display city names
FONT-E       Set default font to 8x14
FONT-M       Set default font to 8x8
FONT-S       Set default font to 4x8
FONT-T       Set default font to 4x6
FONT-X       Set default font to external font
FONTLOAD     Loads an external font
SYMDEF       Loads an external symbol
SYMBOL       Display an external symbol
GRID         Display GeoClock Selected lat/long lines
NOGRID       Do not display GeoClock Selected lat/long lines
NOLINE       Do not display incremental latitude/longitude lines
LINE         Set lat/long line increment and display lines
TLINC        Set latitude line increment
GLINC        Set longitude line increment
GLSPEC       Display specific longitude line
TLSPEC       Display specific latitude line
CLINE        Clear all specific latitude/longitude lines
LINEPERM     Make TLSPEC and GLSPEC lines permanent
HIDELL       Do not show Latitude/Longitude values
SHOWLL       Show Latitude/Longitude values
LLCOLOR      Set color and style of lat/long lines and labels
INCLUDE      Include data file
GINCLUDE     Globe include data file
DRAWLINE     Draw line on map
VECTOR       Continue a line started by drawline
DRAWCIRCLE   Draw circle on map
DRAWFCIRCLE  Draw filled circle on map
*** Sun and Moon Display Control
SUNANGLE     Sun rise/set definition
SUNLIGHT     Terminator definition
TWILIGHT     Twilight terminator definition
TLMASK       Twilight area pattern
NOFILL       Do not display building of sunlit area
NORMAL       Normal Display
LIGHT        All sunlight is displayed
DARK         No sunlight is displayed
BLANK        Highlighting is not used
MOON         Control display of moon
EPHEMERIS    Control display of ephemeris data with Distance
*** Time, Zone and Format Control
T            Set new time
S            Speed to time change
U            Change display update interval
R            Reset time and speed
*** Special Commands
C            Enter a command
K            Go back to previous map displayed
D            Measure distance (two point)
@            Measure distance (three point)
Z            Select another map (Zoom)
L            Toggle between Lat/Long displayed
Y            Toggle city and country display
NETWORK@server@local@  Network control
FAST         Use reduced accuracy but faster calculations
SLOW         Use high accuracy but slower calculations
387          Activate speedup with 80387 or i486
HAMCD        Specify HAM CD-ROM data base
HAMDB        Specify HAM data base - maximum speed configuration
HAMDBX       Specify HAM data base - minimum memory configuration
HAM          Activate HAM features
NOHAM        Deactivate HAM features
CALL         Specify initial call sign
NOBLINK      Required for some Trident graphics boards
FLICKER      Required for some Trident graphics boards
QUIET        Does not beep on cycle completion
SOUND        Beeps on cycle completion
HALT         Terminate script and return to DOS
REPEAT       Start script over from first line
SCRIPT       Invoke specific script
WCGLOBE      Set parameters for GeoGlobe program
ZOOMFRACT    Set screen active area for zoom
*** Mouse, Graphics, and Color Control
FMOUSE       Use fast mouse reset
EMOUSE       Mouse with EGA restrictions
RMOUSE       Reset mouse with video mode switch
MOUSEX       Control Mouse/Icon interaction
SAVER        Special screen save mouse/keyboard action
ICONSIZE     Set initial icon size
EGA          Specify EGA graphics system
VGA          Specify VGA graphics system
SVGA         Specify 800x600 super VGA (SVGA) graphics system
SHOWVGA      Convert EGA maps to VGA for display
SHOWSVGA     Convert EGA and VGA maps to SVGA for display
CSET         Color change menu
COLOR        Set color
ECOLOR       Set color for elevation maps
TEXTBG       Set text background color
MCOLOR       Set color for Distance cursors
FCOLOR       Set map frame color
*** Zoom (Z)
*** Distance Measurement (D)
*** Scripts







 4.2  Icon/Mouse Controlled Commands

  Each of these commands is activated by moving the mouse over the icon and
clicking the left button.  There is a keyboard equivalent for each of these
commands.  The Icon bar itself can be removed by moving the mouse cursor
off the screen, or pressing the ALT key.  Moving the mouse back on the
screen, or pressing ALT again, will return the icon bar.

Quit           Quit to DOS
  Clicking on this icon, pressing Q, or pressing Escape twice quickly
  stops GeoClock and returns to DOS.

Reset          Reset time and speed
  Clicking on this icon, or pressing R, sets the time, speed of time
  passage, and update interval to their default values.  The icon is not
  displayed unless at least one of these values is not the default value.

Help           Online help
  Clicking on this icon activates the online help system. The top level
  menu of the Help system gives a list of a number of topics. The selected
  topic is highlighted, and the selection can be changed by using the
  arrow keys. More details can be obtained about the selected topic by
  pressing the ENTER key. The cursor keys, including the arrows, page up,
  page down, home, and end can be used to scroll through the information.
  ESCAPE returns to the top HELP menu. The + and - keys select the next
  and previous topic without returning to the top menu.  The mouse can be
  used to control help.  Click the left button on a topic will display
  that topic.  Clicking the right mouse button will return to the previous
  topic (or exit help if you are at the main menu).  Clicking the == icon
  also will return to the previous topic.  Clicking any of the symbols at
  the bottom of the screen will have the same effect as pressing that key
  (e.g., clicking the HOME symbol will move the beginning of the current
  topic).

Set            Set time
  Clicking on this icon, or pressing T, pops up a time window and allows
  you the edit the current time in yyyy/mm/dd hh:mm:ss format.  This does
  not change your PC's clock.  All times in GeoClock use the 24 hour
  format.  You can use the cursor keys to edit the time, use ENTER to
  accept the new time, or ESC or click outside the box to reject the new
  time.

Speed          Set speed to time passage
  Clicking on this icon or pressing S, prompts you for the rate of change
  of time per display update.  The prompt asks for the number of hours
  (possibly fractional or negative) for the displayed clock to be
  incremented during each cycle, e.g., 0.25 for 15 minutes every 1 to 20
  second cycle. The hour:minutes:seconds format can be used if desired,
  e.g., 0:15 for 15 minutes, or 0:0:5 for five seconds.

Country/City   Toggle between city and country display
  Clicking on this icon, or pressing Y, toggles between display of city
  names and country names.

Lat-Long       Toggle latitude/longitude lines
  Clicking on this icons alternately displays and hides latitude and
longitudes lines.  It is equivalent to the GRID and NOGRID commands.

Distance       Measure Distances
  Clicking on this icon, or pressing D, starts a special two point
  distance measuring function.  One point is fixed and the other is
  controlled by the mouse.  Pressing a mouse button, or pressing ENTER,
  moves the first point to the current mouse position.  At the bottom of
  the screen, the coordinates of both points, the distance between them,
  and the azimuths between them are displayed.  To exit the distance
  function, click the reset icon in the upper right, or press ESCAPE.  In
  this function, if you do not have a physical mouse and a VGA or better,
  the cursor can be moved with the arrow keys, and shift-arrow will move
  the cursor 8 times faster than arrow.

MapList        Zoom up to next higher level map
  Clicking on this icon, or pressing the M key, displays a list of all
  available maps.  The arrow keys or mouse can be used to select the
  desired map, and pressing ENTER or clicking on a map name will display
  that map.

Zoom           Zoom in or out
  Clicking the left mouse button anywhere on the screen (except on the
  icon bar), zooms in to the lowest level (most detailed) map containing
  the point under the cursor.  Clicking the right mouse button selects the
  next higher level map in the zoom hierarchy.

GeoGlobe       Start GeoGlobe program
  If you have the GeoGlobe program and start GeoClock using GEOCLK.COM
  (this the default start program), clicking this icon will start
  GeoGlobe.  When GeoGlobe is terminated, GeoClock will restart.  The
  GeoGlobe icon appears only if the GeoGlobe program is named GEOGLOBE.EXE
  and is in the same directory as GeoClock.







 4.3  Help Control

HELP (or H)  Activates help system
?            Activates help system
F1           Function Key 1 - Activates help system
  The help system can be activated any time a map is displayed (except
  when Zoom or Distance is active) by clicking the help icon, or pressing
  the ? key or function key 1. It can also be activated by entering HELP
  or ? at a command prompt. The top level menu of the Help system gives a
  list of a number of topics. The selected topic is highlighted, and the
  selection can be changed by using the arrow keys. More details can be
  obtained about the selected topic by pressing the ENTER key. The cursor
  keys, including the arrows, page up, page down, home, and end can be
  used to scroll through the information. ESCAPE returns to the top HELP
  menu. The + and - keys select the next and previous topic without
  returning to the top menu.  The mouse can be used to control help.
  Click the left button on a topic will display that topic.  Clicking the
  right mouse button will return to the previous topic (or exit help if
  you are at the main menu).  Clicking the == icon also will return to the
  previous topic.  Clicking any of the symbols at the bottom of the screen
  will have the same effect as pressing that key (e.g., clicking the HOME
  symbol will move the beginning of the current topic).
REM          Remark - remainder of line is ignored
  Remarks can be used within *.dat files for additional documentation of
  the various text files you may change to customize GeoClock maps.
Printing help
  You can print the help information for a particular topic or print the
  entire help text.  To print a particular topic, bring up the detailed
  help screen for that topic and press ALT-P.  To print all the help
  topics, bring up the help main menu screen and press ALT-P.  The menu
  will prompt you for a device name (LPT1 selects printer 1, but you can
  print to any device or to a file), and the number of lines printed per
  page (select 0 for a laser printer, because laser printers automatically
  produce margins at the top and bottom of every page).  Finally, press
  ENTER to start printing, or ESCAPE to abort the print.







 4.4  Map Selection

M            compact Map list
  Pressing this key displays a list of maps in compact form.  The arrow
  keys can be used to select a particular map.  Pressing ENTER displays
  the selected map.  The list is normally sorted in order of decreasing
  size.  It can be sorted in alphabetic order of title by pressing T, or
  in numeric order by pressing N.
F            Find map in list
  Pressing this key displays a list of available maps.  The arrow keys can
  be used to select a specific map from this list.  Pressing ENTER dis-
  plays the selected map.  The list is normally sorted in order of
  decreasing size.  It can be sorted in alphabetic order of title by
  pressing T, or in numeric order by pressing N.
MAP          Select MAP from list
  This command works identically to F.  If it is included on the GeoClock
  command line (for example, GEOCLK MAP), the selection menu will appear
  before the program starts.
MAPn         Changes to MAP number n
  This command displays a specific map.  For example, MAP5 displays map
  number 5.  If this command in included in GECONFIG.DAT, the map
  specified will appear as the first map displayed.
MAPPLUSn     Selects the next sequential map using sort method n
  This command chooses the next map in sequence.  If n is 1, it chooses
  the next high map number.  If n is 2, it chooses the next map in
  alphabetical order.  If n is some other number, it chooses the next map
  in coverage area.  If n is missing, it uses the method last selected in
  the "M"aplist or "F"indMap function.
MAPMINUSn    Selects the previous sequential map using sort method n
  This command chooses the previous sequential map using the sort mathod
  described above.
RANDOM       Picks a map at random
  This command chooses another map at random from those available in the
  directory (the same list as produced by the "F" command).
NOMAP
  The map annotation and sun highlighting from the previous map is
  displayed without the map background.
MAPCENTERn   Center world map on longitude n
  Centers any rectangular projection world map on longitude n (more or
  less).  For example, MAPCENTER-77 centers the world map on Washington.
  It does not have any effect on non-rectangular projection or non-world
  maps. Like FCOLOR, this command does not take effect immediately if
  used in the GEOn.DAT files  (except GEOCLOCK.DAT) or scripts, but does
  work correctly in GECONFIG.DAT, the command line, and "P".







 4.5  Map Annotation

Asterisks (*) indicate default values in GeoClock

FULL *       City, sun rise/set, local time, sun position legend
  GeoClock can display a time legend at the bottom of the screen.  FULL
  displays the full range of time and sun-related information on the
  legend.  This includes primary city name, its time and date, including
  local time zone name, and sunrise and sunset time.  (The time zone is
  the one specified in the corresponding GEO*.DAT file.)  It shows sunrise
  and sunset times for the primary city, the sun's subpoint coordinates,
  and the azimuth and elevation of the sun from the primary city.  The
  format of the time and date can be controlled with other commands (see
  "Time, Zone, and Format Control").
NONE         No legend
TIME         Local time only legend
SUN          City, sun rise/set, local time legend
DATECHANGEn  Control display of next/previous date
  If n is 0, the date is not indicated.  If n is 1, the local time shows
  a ":" if the local date is the same as the current date, it shows an
  up-arrow if the local date is one day ahead of the current date, and
  it shows a down-arrow of the local date is one day behind the current
  date.

HTA          Display specified city as primary city on all maps
  HTA/Lat/Long/ZoneCode/CityName   forces the specified city to be the
  primary city on all maps.  It overrides the first and second lines in
  every GEOn.DAT file, and thus is a shortcut method to configure GeoClock
  for your city.  For example, HTA/38.90/-77.03/ET/Washington   forces
  Washington to be the primary city on all maps, and displays ET (Eastern
  Time) for all ephemeris data.  HTA is an acronym from Home Town Always.
  HTA with no parameters uses the current primary city.
HTS          Display specified city as primary city on maps containing it
  HTS/Lat/Long/ZoneCode/CityName  It works identically to HTA, except that
  it uses the specified city only if the city appears on the map.  For
  example, HTS/38.90/-77.03/ET/Washington   would force Washington to be
  the primary city on MAP2 (US - 48 States), but not on MAP5 (Europe).
  HTS is an acronym for Home Town Showing.  HTS with no parameters uses
  the current primary city.
HTN          Do not display specified city as primary city
  HTN/Lat/Long/ZoneCode/CityName  It works identically to HTA, except that
  it does not display the specified city.  HTN is an acronym for Home Town
  Never.  HTN with no parameters uses the current primary city.
NOHT         Same as HTN.
MARKLIMIT    Control display of cities close to HTA/HTS city
  This sets the minimum distance from the home town city that a city must
  be to be displayed.  For example, MARKLIMIT5 means that any mark within
  5 pixels x and y of the home town mark will not be displayed.  The
  distances can be set independently, e.g., MARLIMIT5/10 means x of 5 and
  y of 10.  The default is -1, or no restriction.

HIDEMN *     Do not display map name and number
  Map number and name are not displayed.
SHOWMN       Display map name and number
  The map number and name are displayed in the upper right corner of the
  map.  This is especially useful with the ZOOM function.
POSMN        Set position and color of map name and number
  POSMNxp/yp/fg/bg  xp is the horizontal (x) position of the title.  0
  means center, x > 0 means start the title at x pixels right of the left
  edge, x < 0 means end the title x pixels left of the right edge.  The
  default value is -1.  yp is the vertical (y) position of the title.  0
  means center, y > 0 means the upper edge of the title is y pixels below
  the upper edge, y < 0 means the lower edge of the title is y pixel above
  the bottom edge.  1 is the default.  fg is the text color, and 7 is the
  default.  bg is the background color.  -1 means transparent and is the
  default.
TEXT         Display text on all maps
  TEXTx/y/font/color/bg*text     No spaces before the * are allowed.  x
  is the horizontal coordinate of the starting pixel for the string (if
  negative, from the right of the screen), y is the vertical coordinate
  of the starting pixel (if negative, from the bottom of the screen,
  font is 0 for 8x14, 1 for 4x6, 2 for 8x8, 3 for 4x8, and 4 for the
  Xfont.  color is the color number for the text, and bg is the
  background color (-1 means transparent).  The text itself can be
  anything. The underscore (_) is interpreted as a space.
NAUTICAL     Display distances in nautical miles
STATUTE  *   Display distances in statute miles







 4.6  Time Control and Display

Asterisks (*) indicate default values in GeoClock

    GeoClock displays time in a most significant to least significant
format, i.e., year/month/day hour/minute/second.  The following commands
control the details of the time display format.
YEAR2 *      Show 2 digit year  (e.g., 91/05/01 12:14:45)
YEAR4        Show 4 digit year  (e.g., 1991/05/01 12:14:45
NOMONTH *    Show month number rather than name.
SHOWMONTH    Show month name rather than number (91 MAY 01 12:14:45).
  The standard 3 letter English abbreviations are used by default. The
  text for the month names can be specified by giving the 12 strings to be
  used for the 12 months. For example:
  SHOWMONTH JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
NODAY *      Does not show display the day of the week.
SHOWDAY      Show day of week
  This command displays the day of the week (1991/05/01 WED 12:14:45). As
  in SHOWMONTH, the default is the standard 3 letter English abbreviation,
  but other names can be specified:
  SHOWDAY SUN MON TUE WED THU FRI SAT
NOSECONDS    Shows time to last minute
  This command shows time to the last minute (1991/05/01 12:14)
SHOWSECONDS * Show time to nearest second
  This command shows time to the nearest second (1991/05/01 12:14:45).
DST          Control Daylight Saving Time
  The method GeoClock uses to handle summer time when current data is not
  available in GECONFIG.DAT is close, but not perfect.  This command
  specifies for which years the GeoClock computed correction is to be
  applied.  By default, GeoClock does not use summer time before 1980.
     DST is used to change this date.  The syntax is:

  DST year1 year2 extrapolation
     Year1 is the earliest year in which to use summer time under the
  current specification, and year2 is the latest year in which to use
  summer time.  If year2 is omitted, there is no upper limit.  For
  example, DST 1950 specifies that summer time is to be used from 1950 on,
  while DST 1985 1995 specifies that summer time is to be used only
  between 1985 and 1995.  "extrapolation" specifies the algorithm used to
  estimate summer time dates which are not included in the GEOZONES file.
  If extrapolation is 1, the date used is the one closest same day of the
  week to the specified date (for example, 95/04/02 (a Sunday) would
  become 96/03/31 (also a Sunday).  If "extrapolation" is missing or any
  other value, and the original date is in the first or last week of the
  month, the new date is the same day of the week also in the first or
  last week of the month.  For example, 95/04/02 would become 96/04/07.

ZONE         Define time zone
  This command defines a time zone: it relates the time zone to the
  standard time zone (variously called Greenwich Mean Time (GMT) or
  Universal Time Coordinated (UTC) or Zulu Time (Z)); it specifies the
  dates and times when the zone changes to and from summer time; and it
  names the time zone and the standard and summer times.  As an example,
  U.S. Eastern Time is specified by:
  ZONE   ET     EST     -5     EDT     -4     91/04/07:7   91/10/27:7
  ET is the name the time zone is referred to by all GeoClock commands.
  The definition states that the zone is called EST and is 5 hours behind
  GMT, except between 91/04/07 0700 GMT and 91/10/27 0700 GMT, when it is
  called EDT and is 4 hours behind GMT.
  If the offset to GMT is 100 or larger, the time zone will give true
  local sun time (i.e., the sun is at its highest elevation at exactly
  12:00 every day).  A special time zone named ST (for sun-time) is
  defined in the GEOZONES.DAT file for this zone.
  If the ZONE commands are not for the correct year, GeoClock will
  automatically update them by changing each date to the closest date in
  the correct year which falls on the same day of the week.
PCZONE       Specify PC time zone
  The PCZONE command sets the relationship between the local time on the
  PC's clock and GMT, i.e., declares which time zone the PC's clock is in.
  It takes one parameter - a time zone code, as defined in the ZONE
  command. For example, if you use Eastern Time, specify:
  PCZONE ET
  This command is best used in the GECONFIG.DAT file, and it must follow
  the ZONE command that it references.







 4.7  Map Display

Asterisks (*) indicate default values in GeoClock

DATAFILE     Select extension for data files
  This command sets the extension to be used for GEOn files.  By default,
  it is DAT (the previous default).  This allows multiple sets of GEOn
  files to be used with the maps.  If the extension does not exist, then
  DAT is used.  For example, DATAFILE XYZ would first check GEOn.XYZ, and
  if it does not exist, then check GEOn.DAT, and it that did not exist,
  check GEOCLOCK.DAT.
COUNTRY      Display country names
  Supporting the above capability is a control character used after the !
  in GEOn entries: Z.  Any city (or entry in the GEOn.DAT file) with a !Z
  is not displayed unless the COUNTRY command has been given.  CITY
  reverts back to normal display, and cities with the !Z are not
  displayed.  In the data files included, this capability is used to
  toggle between normal display of cities and times, and display of
  country names.
NOMARK *     Do not display location markers.
MARK         Display location markers for cities.
FORCEMARK    Always display location markers for cities, regardless of the
  presence of the "N" flag.

NOCITY *     Do not display city names
CITY         Display city names.  The city names and locations are
  contained in the corresponding GEO*.DAT file.  The name is usually
  displayed to the right of the location, but the name may be moved if it
  does not fit.  The location can be controlled by the user, and local
  time can be added (see Advanced Topics).

FONT-E       Set default font to 8x14.  This font size is used for city and
  time display on the maps unless it is overridden by an !E,M,S, or T on
  the corresponding line in GEO*.DAT.
FONT-M *     Set default font to 8x8
FONT-S       Set default font to 4x8
FONT-T       Set default font to 4x6
FONT-X       Set default font to external font
FONTLOAD     Loads an external font
  FONTLOAD filename   loads the external font specified by <filename>
  The format of the external font file is:
  Byte 0   horizontal character width in bits (w)
  Byte 1   vertical character height in bits (h)
  Byte 2   first character in table (c1)
  Byte 3   last character in table (c2)
  Bytes 4 through 4+(c2-c1+1)*h*entier((w+7)/8)  character bits
  If the requested character is not in the c1..c2 range, the character
  is displayed as c1.

SYMDEF     Load an external symbol definition
   SYMDEF filename   loads the external symbol specified by <filename>.
   The format of the external file is:
   Initial Byte    length      Meaning
    0               2          Number of pixels in the x direction (nx)
    2               2          Number of pixels in the y direction (ny)
    4               2          x pixel corresponding to the symbol center
    6               2          y pixel corresponding to the symbol center
    8               8          Name of symbol (trailing spaces)
    10              nx*ny      Color of pixel (going horizontally from 1 to
                               nx, then vertically from 1 to ny).  0-
                        15 displays as that color.  16-255 is
                 transparent.
  Multiple symbol definitions can be included in a single file by
  concatenating the above structure.
SYMBOL     Displays on external symbol
  SYMBOL  name  lat  long      displays the symbol referred to by <name>
  (defined by a previous SYMDEF command) centered on lat long.  This
  symbol is drawn before any city names or times are drawn, so the
  symbol can be overwritten by this data.
  SYMBOL  filename  lat long      displays the symbol defined in
  <filename> centered on lat long.  This symbol is drawn before any city
  names or times are drawn, so the symbol can be overwritten by this data.
  SYMBOL  filename  name  lat long      displays the symbol defined in
  <filename> and named <name> centered on lat long.  This symbol is drawn
  before any city names or times are drawn, so the symbol can be
  overwritten by this data.

GRID         Display GeoClock Selected lat/long lines
  This command overrides all the other Lat/Long commands and display
  GeoClock selected lines.  It is equivalent to LINE, TLINCx, GLINCy, and
  SHOWLL, where x and y are selected by GeoClock on a map by map basis.
NOGRID *     Do not display GeoClock Selected lat/long lines
  This commands negates the GRID command.
NOLINE *     Do not display latitude/longitude lines
  NOLINE removes all latitude/longitude lines from the display.
LINE         Set lat/long line increment and display lines
  This command enables latitude and longitude lines on the display, and
  sets the spacing between the lines. For example, LINE15 draws latitude
  and longitude 15 degrees apart.
TLINC        Set latitude line increment
GLINC        Set longitude line increment
  TLINC and GLINC allow the spacing between latitude and longitude lines
  to be set independently. For example, TLINC 15 and GLINC 30 set the
  latitude spacing to 15 degrees, and the longitude spacing to 30 degrees.
TLSPEC       Specific latitude line
GLSPEC       Specific longitude line
  TLSPEC and GLSPEC allow specific latitude and longitude lines to be
  displayed.  For example, TLSPEC -67 draws a latitude line at 67 degrees
  south (the antarctic circle).  Up to 20 of these special lines can be
  specified.
CLINE        Clear all specific latitude/longitude lines
  CLINE removes all non-permanent special lines from the display.  CLINE1
  removes all line including permanent lines.
LINEPERM     Make TLSPEC and GLSPEC lines permanent
  LINEPERM makes all currently defined TLSPEC and GLSPEC lines permanent,
  i.e., they will be displayed on all maps.  If TLSPEC and GLSPEC commands
  are followed by LINEPERM in GECONFIG.DAT, these lines will be permanent.
  A similar sequence in a GEOn.DAT file will make these lines permanent.
  CLINE1 clear all permanent lines.

HIDELL *     Do not show Latitude/Longitude values
  This command suppresses the latitude and longitude labels.
SHOWLL       Show Latitude/Longitude values
  This command labels all the latitude and longitude lines displayed. The
  labels appear on the top and left edges of the display. The labels may
  overlap other data.  Optionally, SHOWLL can control which axis are
  labeled: SHOWLLn
    n and 1 = 0  show left latitude
    n and 2 = 0  show right latitude
    n and 4 = 0  show top longitude
LLCOLOR      Set color and style of lat/long lines and labels
  This command takes two parameters LLCOLOR a/b.  a is the color number
  for the lat/long lines (the default is 6).  b is the color number for
  the lat/long line labels (the default value is 7).  If a is negative,
  the lines will overwrite all map features, while if a is positive it
  will only overwrite colors 1,2,3 (water, land, and land/water).

INCLUDE (or I)   Include data file
  When contained in a GEOn.DAT file, INCLUDE <file>  suspends reading from
  the file being processed, and processes all commands in the <file>.
  When all commands in that file have been processed, reading resumes from
  the original file.  INCLUDE may be nested up to ten levels.  INCLUDE may
  also be used in response to the "P" command.  In this case, the named
  file will be included at the end of the GEOn.DAT file for the map
  currently displayed.
    The effect of the INCLUDE command will be negated when a new map is
  selected or a new file is specified with INCLUDE.  The INCLUDE command
  can be abbreviated by I (i.e., I DATELINE).  An include file can be set
  on the command line or in a script by using the @ character as a
  separator (e.g., GEOCLK  MAP1  I@dateline).  This syntax is not allowed
  in data files or in response to P or C.
GINCLUDE (or GI)  Global include data file
  The commands works the same as include above, except that the file is
  included on all maps.  Orindarily, the GINCLUDE command would be in
  GECONFIG.DAT, but it can be on the command line (using the @
  character) or in response to P or C.  The command is canceled by
  GINCLUDE or GI with no file name specified.  If both GI and I are
  active on the same map, both files will be processed.
DRAWLINE         Draw line on map
  DRAWLINE lat1 long1 lat2 long2 color   draws a line between (lat1,long1)
  and (lat2,long2) on the current map.  Color is the color in which the
  line will be drawn.  See "Color Control" for an explanation of the use
  of color.  If omitted, color defaults to 5 (yellow).  Example:
  DRAWLINE 38.9 -77.0 34.0 -118.3 0
  draws a line between Washington DC and Los Angeles in color 0.
    The DRAWLINE command cannot be issued from the [C]ommand level.  It
  operates ONLY when contained in a GEO*.DAT file that is processed for
  the map, or in a text file that is appended to a map with the INCLUDE
  command.
VECTOR (or V)     Continue a line
  VECTOR latx longx   draws a line starting at the position of the last
  DRAWLINE or VECTOR, to (latx,longx) using the color specified in the
  last DRAWLINE.  For example, if the following lines immediately follow
  the line in the DRAWLINE example:
  VECTOR  41.83   -87.75
  VECTOR  38.67   -90.25
  a line from Los Angeles to Chicago to St, Louis will be drawn in color
  0.  The VECTOR command may be abbreviated by V (i.e., V 41.83 -87.75).
DRAWCIRCLE        Draw circle on map
  DRAWCIRCLE latcenter longcenter latrad longrad color    draws an ellipse
  centered at (latcenter,longcenter) and with latitude (vertical) radius
  latrad and with longitude (horizontal) radius longrad, and with color
  color. The command operates ONLY when contained in a GEOn.DAT file that
  is processed for the map. Color is the color in which the line will be
  drawn. If omitted, color defaults to 5, which is displayed as yellow.
  Example:
  DRAWCIRCLE  38.9  -77.0  10 20 6
  draws an oval centered on Washington DC that is 10 degrees from the
  center to the northernmost point, and 20 degrees from the center to the
  easternmost point, and in color 6.  Alternatively, the form:
  DRAWCIRCLE latcenter longcenter -radius 0 color   can be used.  This
  draws a circle of the specified radius (in kilometers) in the specified
  color around the specified center point.  For example:
  DRAWCIRCLE  38.9  -77.0  -100 0 6
  draws a 100 km circle in color 6 around Washington DC.  The negative
  sign in front of the radius, and the 0 after the radius, are required to
  ensure compatibility with the older system.
DRAWFCIRCLE       Draw a filled circle on map
  DRAWFCIRCLE has the same syntax as DRAWCIRCLE, except that the circle or
  ellipse drawn is solid rather than outlined.







 4.8  Sun and Moon Display Control

SUNLIGHT     Terminator definition
  SUNLIGHT angle   specifies the sun's elevation angle for the terminator.
  The default is -0.8333, which corresponds to apparent sunrise and
  sunset, when the edge of the sun is just visible.  0 corresponds to the
  geometric terminator, which divides the earth into two equal halves.
TWILIGHT     Twilight terminator definition
  TWILIGHT angle   specifies the sun's elevation angle for the twilight
  terminator.  The default is 0.  -6.00 corresponds to civil twilight, -12
  corresponds to nautical twilight, and -18 corresponds to astronomical
  twilight.  If this angle is greater than or equal to the SUNLIGHT
  parameter, the twilight area is not displayed.
TLMASK       Twilight area pattern
  TLMASK n   specifies the fraction (in 16ths) of halftoning for twilight
  display.  4 is the default, which gives 1/4 light and 3/4 dark for the
  twilight area.  You may have to experiment with this value to get the
  best display for your monitor.  A value of 4 may give a better effect,
  particularly if you wish to emphasize the terminator relatively to the
  twilight line.
NOFILL       Do not display building of sunlit area
  Does not perform area fill operations directly to the screen when a map
  is initially displayed.  The map will be displayed, and after a short
  delay the entire sunlit area will be displayed.  This sometimes solves
  stack overflow errors during fill with some graphics cards.
SUNANGLE     Sun rise/set definition
  SUNANGLE angle   sets the elevation angle of the sun used to compute
  sunrise and set.  The default is -0.8333 degree, which corresponds to
  the sun just breaking the horizon, considering refraction effects. This
  parameter does not affect the terminator line calculations.

NORMAL *     Normal Display
  This highlights the sunlit area and displays the sun symbol at the sun's
  subpoint.
LIGHT        All sunlight is displayed
  This highlights the entire screen, and does not display the sun symbol.
  This often provides a better display of details of small-area maps, on
  which terminator display may be unimportant, e.g., city maps.
DARK         No sunlight is displayed
  This does not highlight any of the screen, and does not display the sun
  symbol.
BLANK        Highlighting is not used
  This does not perform any highlighting.  This is appropriate for some
  specialized maps which use more than 7 colors.
MOONdisp     Control display of moon
  If disp is 0 or omitted, no moon is displayed.  If disp is 1, a moon
  symbol is displayed with approximate phase information over the
  correct sub-point.  If disp is 2, the text moon illumination fraction
  is displayed with the moon symbol.  If disp is 3, the symbol,
  illumination, lat, long, azimuth, and elevation are all displayed.  If
  disp is increased by 4, the moon is displayed using the calendar
  convention (i.e., the moon looks like the symbol in printed
  calendars).  For example, if disp is 6, the moon symbol is displayed
  using the calendar convention, and the moon illumination fraction is
  displayed in text.
EPHEMERISdisp  Control display of ephemeris data with the Distance
  function.  If disp is 0 or omitted, only coordinates and distances are
  displayed with the distance function.  If disp is 1, the current local
  time and time zone are displayed, along with the sun rise, sun set,
  sun azimuth, and sun elevation, for the selected point.







 4.9  Time, Zone and Format Control

These commands are special - they are activated by pressing a letter key
while a map is displayed.  They can also be used in GE*.DAT files, in
response to a "P" prompt, and on the command line.
T            Set new time
  Pressing the T key prompts you for a new display time in yy/mm/dd
  hh:mm:ss format.  This does not change your PC's clock.  All times in
  GeoClock use the 24 hour format.  The EGA/VGA/SVGA version shows a pop-
  up window with this command.  You can use the cursor keys to edit the
  time, use ENTER to accept the new time, or ESC to reject the new time.
  If this command is used on the command line or in a DAT file, the
  included data is interpreted as year month day hour minute second.  The
  data must be given with no extra characters, and exactly two digits per
  item.  Missing data is set to 2000/01/01 00:00:00.  For example,
  T9205151207 is taken as 1992/05/15  12:07:00.  A four digit year is
  allowed.  When used on the command line or in a DAT file, the data may
  have a + or - followed by a number.  With this format, the current
  vertual time is incremented or decremented by the specified number of
  days.  For example, T+30 increments the time by 30 days, while T-0.25
  decrements the time by 1/4 day = 6 hours.
S            Speed to time change
  Pressing the S key prompts you for the rate of change of time per
  display update.  The prompt asks for the number of hours (possibly
  fractional or negative) for the displayed clock to be incremented during
  each cycle, e.g., 0.25 for 15 minutes every 1 to 20 second cycle. The
  hour:minutes:seconds format can be used if desired, e.g., 0:15 for 15
  minutes, or 0:0:5 for five seconds.
U            Change display update interval
  Pressing the U key prompts you for the screen update interval in
  seconds. When this value is entered, the display is immediately drawn.
  Subsequently, the screen in updated at the specified interval and
  synchronized with the clock. Thus, if 15 is specified, the screen will
  be updated at 0, 15, 30, and 45 seconds past the minute. If your
  computer is not fast enough to achieve the specified interval, the
  smallest integer multiple of this interval which works will be used.
R            Reset time and speed
  Pressing this key restores the display time to the current time, and the
  display update rate to real time.  R "undoes" F, T, and U.







 4.10 Special Commands

The first seven commands are special - they are activated by pressing a
letter key while a map is being displayed.
C            Enter a command
  Pressing this letter key brings up a box for entering a command.  Type
  the command and any parameters, followed by ENTER.  The command will
  take effect immediately.
K            Go back to previous map displayed
  Pressing the K key returns the display to the previous map which was
  displayed.  This is useful if you want to switch back and forth between
  two maps.
D            Measure distance (two point)
  Pressing the key starts the distance measuring function.  This function
  is available only to registered users.  See "Distance Measurement" for
  more information.  This function only works with VGA and better
  displays.
@            Measure distance (three point)
  Pressing the key starts the distance measuring function.  This function
  is available only to registered users.  See "Distance Measurement" for
  more information.  This function works with EGA and better displays.
Z            Select another map
  Pressing the key starts the "Zoom" function.  This function is available
  only to registered users.  It is not a true zoom, but selects maps which
  contain the point under the cursor.  See "Zoom" for more information.
  This function works with both EGA and VGA or better displays.
L            Toggle between Lat/Long displayed
  Pressing this key toggles between GRID and NOGRID.
Y            Toggle city and country display
  Pressing this key toggles between CITY and COUNTRY.

NETWORK@server@local@  Network control
  This command sets GeoClock to run in network mode.  For every file to be
read, the directory "local" is check, and if the file exists there, it is
used.  If not, the directory "server" is used.  When a file is written, it
is always written to the "local" directory.  Usually, GeoClock and all its
files will be installed in the "server" directory, and each user will have
his own "local".  The user can then customize his GeoClock without
affecting other users.  Ordinarily, the NETWORK command should be on the
command line (FILE/PROPERTIES/COMMANDLINE in Windows 3.x).  For example,
C:\SERVER\GEO\GEOCKWIN.EXE  NETWORK@C:\SERVER\GEO@X:\LOCAL\GEO@
will start GeoClock using C:\SERVER\GEO as the server directory, and
X:\LOCAL\GEO as the local directory.
  A special form of the command is  NETWORK  with no additional characters.
In this case, GeoCLock uses the directory containing the GEOCKWIN.EXE file
as the server directory, and the current default directory as the local
directory.

FAST         Use reduced accuracy but faster calculations
  Forces GeoClock to use a faster but slightly less accurate algorithm for
  drawing the sunlit area. This is the default for systems without an
  80x87.
SLOW         Use high accuracy but slower calculations
  Forces GeoClock to use the high accuracy algorithm for drawing the
  sunlit area.  This is the default for systems with an 80x87. On systems
  with an 80x87, the difference in speed between SLOW and FAST is negli-
  gible, while on those systems without an 80x87, FAST is approximately
  twice the speed of SLOW.  These options do not effect polar,
  orthoscopic, or azimuthal-equidistance maps.
387          Activate speedup with 80387 or i486
  This command activates the use of special 387/486 commands which speed
  up calculations, especially on polar, orthoscopic, and azimuthal-
  equidistance maps. If you do not have a 387 type coprocessor, the
  results of using this command are unpredictable. It MAY work on IIT and
  CYRIX 287s, and Intel 287XLs.

The following five commands control the optional HAM features.
HAMCD        Specify option HAM CD-ROM data base
HAMCD file
  specifies that the QRZ or BuckMaster HamCall (April 95 and earlier)
  CDROM is loaded and should be used to obtain extra information about US
  call signs.  If the file parameter is missing, all online local CDROM
  drives will be checked for the data base.  This will almost always
  correctly identify the CD, but you may specify the complete path to the
  data base (for example, HAMCD D:\CALLBK\CALLBKC.DAT or HAMCD
  D:\HAM0\HAMCALL.129 ) if GeoClock cannot automatically locate this data
  base.  When a call sign is parsed, the CD will be checked first.  If the
  call is not found, the GeoClock HAM data base (see below) will be used.
HAMDB        Specify HAM data base - maximum speed configuration
  HAMDB file   loads the HAM call sign data base from file the named file.
  Only the first occurrence of this command in a GeoClock execution is
  effective (i.e., the data base will not be reloaded or changed). A good
  place for this command is in the GEOn.DAT file corresponding to your HAM
  map. The HAM data base and other required files are an extra cost option
  in GeoClock.
HAMDBX       Specify HAM data base - minimum memory configuration
  HAMDBX file   specifies the file with the HAM data base.  Whenever a
  call sign needs to be analyzed, the data base is loaded into temporary
  memory, and the memory is released after analysis.  This slows the
  analysis slightly, but requires about 60Kb less RAM.  If you are
  shelling to GeoClock from another program and get Error 203 messages whe
  you use the HAM features, placing this command in GECONFIG.DAT may solve
  the problem.
HAM          Activate HAM features
  This command activates the HAM features on azimuthal-equidistance maps.
  A good place for this command is in the GEOn.DAT file corresponding to
  your HAM map.
NOHAM        Deactivate HAM features
CALL         Specify initial call sign
  This commands allows the initial call sign, when a HAM map is brought
  up, to be specified.  For example, GEOCLK MAP9009 CALL=K3NA   will cause
  the HAM package to be activated with K3NA data displayed.  The last
  displayed call sign will be displayed after switching away from and then
  back to a HAM map.

The following two commands may be needed to control screen flickering or
flashing on some graphics boards that do not follow the IBM standard
exactly.
NOBLINK      Required for some Trident graphics boards
  This command prevents the markers from blinking on the Distance screen
  on some graphics adapters. You may want to use the MCOLOR command with
  NOBLINK to improve marker readability.
FLICKER      Required for some Trident graphics boards
  This command forces GeoClock to bypass the video BIOS and issue changes
  to the video memory start address and palette directly to the video
  hardware. This is necessary to prevent flickering or blinking of the
  display on some graphics adapters.

QUIET        Do not beep on cycle completion (default)
SOUND        Beep on cycle completion
HALT         Terminate script and return to DOS
REPEAT       Start script over from first line
SCRIPT       Invoke a specific script
  SCRIPTx   invokes script x (i.e., the file GEOSCRx.DAT).  x may be any
  number.  This is especially useful from the command line.  Note that if
  GEOSCR0.DAT exists, it is automatically invoked when GeoClock starts
  unless the SCRIPTx command is in the GECONFIG.DAT file or on the command
  line.
WCGLOBE      Set parameters for GeoGlobe program
  This command sets the parameters for the GeoGlobe program.  All the
  parameters on the WCGLOBE line are passed to GeoGlobe when GeoGlobe is
  started by clicking the Globe icon.  For example
  WCGLOBE  P /X
  Causes GeoGlobe to be started with the P (preload the data base) and /X
  (display axis) parameters when the Globe icon is clicked.
ZOOMFRACT    Set screen active area for zoom
  This command sets the size of the active area on the map for zoom to
  prevent zoom to areas  too close to the screen edge, and to allow map to
  map lateral zooming.  ZOOMFRACT1.0 allows zooming to any area on the
  screen.  ZOOMFRACT0.95, for example, does not allow zooming closer to
  the edge than 5% of the screen dimensions.  This parameter also affects
  the Where function, ensuring that the selected city is not too close to
  the edge of the map.  One consequence of this is that clicking near the
  edge of the map will bring up the highest resolution map containing that
  point but not near the edge, so the zoom function can be used to
  navagate laterally through the maps.







 4.11 Mouse, Graphics, and Color Control

The commands below specify the capabilities of your color graphics system
and mouse. See also "Configuring for EGA/VGA/SVGA Graphics Systems."

FMOUSE       Use fast mouse reset.
  Use the fast mouse software reset (function 21h) to initialize the
  mouse.  Microsoft and some other mice use a very slow (several second)
  hardware reset for the normal mouse initialize function, while the
  software reset works equally well.  If there is a long delay when using
  Z or D the first time these functions are used, adding FMOUSE to the
  GECONFIG.DAT file may improve the speed significantly.  Some mice do not
  recognize the software reset.  In this case, the mouse will not work
  with FMOUSE.
EMOUSE       Mouse with EGA restrictions
  The EGA display does not support some mouse functions because the
  display's state cannot always be determined.  If you have a true EGA
  system, rather than a VGA or better, this statement should be included
  in GECONFIG.DAT or the mouse may interfere with correct display.  It is
  automatically added by GEOSETUP if appropriate.
RMOUSEn      Reset mouse with video mode switch
  This parameter controls mouse resets whenever the video mode is changed.
  While this should happen automatically, some mouse drivers, including
  the standard mouse driver with OS/2, do not follow this standard.  By
  default, GeoClock resets the mouse every time the video mode is
  switched.  If the mouse works but mode switches are very slow, or the
  system hangs sometimes when the video mode switches, try RMOUSE1.
MOUSEX       Control Mouse/Icon interaction
  This controls the interaction between the mouse and the icon bar.

  MOUSEX0   The icon bar and mouse cursor are not displayed until the
  mouse is moved or ALT is pressed.  When a new map is displayed, the icon
  bar and cursor initially are not displayed.  This is intended for
  scripts.

  MOUSEX1   The icon bar is controlled only by ALT.  Mouse movement has no
  effect on the icon bar.  The icon bar state is preserved through map
  changes.

  MOUSEX2   The icon bar is never displayed.

  MOUSEX3   The icon bar is controlled by ALT and by the mouse moving off
  and on the screen.  The icon bar state is preserved over map changes.
  This is the default when GeoClock starts.

SAVER        Special screen save mouse/keyboard action
  When this command is execute, *any* mouse movement or click, or any
  keystroke, will cause GeoClock to terminate.  This is usefull when
  GeoClock is used as a screen saver.

ICONSIZE     Set initial icon size
  ICONSIZE1 sets the initial icon to an 8 pixel bar with the function
  names, rather than the 46 pixel bar with true icons.  The ALT key will
  toggle the icon size.

EGA          Specify EGA graphics system
  This command should be included in the GECONFIG.DAT file if you have an
  EGA system. The command prevents VGA and SVGA maps from being displayed.
VGA          Specify VGA graphics system
  This command specifies that you have a VGA system. This is the default
  for GeoClock, so the command is usually not required. If you have a
  super EGA (one that supports 640x480) rather than a true VGA, this
  command may be required. The format of the command is VGAa/b/c/d , where
  a, b, c, and d are the decimal values of the AX, BX, CX, and DX
  registers to enter the 640x480x16 graphics mode by executing INT 10.  If
  you do not have a true VGA, but an EGA capable of 640x480 graphics, you
  may have to add the EMOUSE command to GECONFIG.DAT.
SVGA         Specify 800x600 super VGA (SVGA) graphics system
  This command specifies that you have an 800x600x16 color Super VGA
  (SVGA) display. The format of the command is SVGAa/b/c/d , where a, b,
  c, and d are the decimal vales of the AX, BX, CX, and DX registers to
  enter the 800x600x16 graphics mode by executing INT 10. If the
  parameters are omitted, the VESA standard parameters are used.
  "Configuring for EGA/VGA/SVGA Graphics Systems" has parameter values for
  a number of SVGA manufacturers.
SHOWVGA      Convert EGA maps to VGA format for display
  This command forces all EGA maps to be displayed in VGA format. GeoClock
  converts the maps on the fly by duplicating some horizontal lines. Using
  this command allows the higher resolution VGA characters and lines to be
  displayed on EGA maps, and prevents your graphics system from changing
  video modes when switching between EGA and VGA maps. It does NOT enhance
  the resolution of EGA maps.
SHOWSVGA     Convert EGA and VGA maps to SVGA format for display
  This command forces all EGA and VGA maps to be displayed in SVGA format.
  GeoClock converts the maps on the fly by duplicating some horizontal and
  vertical lines. Using this command allows the higher resolution SVGA
  characters and lines to be displayed on EGA and VGA maps, and prevents
  your graphics system from changing video modes when switching between
  EGA, VGA, and SVGA maps. It does NOT enhance the resolution of EGA maps.

All the supported graphics adapters provides for the simultaneous display
of 16 colors from a palette of 64.  The 16 colors that can be displayed
simultaneously are used to represent 16 features displayed by GeoClock.
See "Colors and Default Colors" (4.7) for details.
    The following three commands are used to control the colors displayed
on the screen for these 16 features.

CSET         Color change menu
  This command is activated by pressing P (to get the command prompt),
  followed by CSET.  A menu is displayed with the 16 color feature names,
  numbers, and color values.  The color values are expressed by combi-
  nations of the following letters:
       B  = bright blue              b = dim blue
       G  = bright green             g = dim green
       R  = bright red               r = dim red
  For example, white is rgbRGB (r + R = full red, full green, full blue),
  bright yellow is rgbRG (full red, full green, dim blue), and grey is rgb
  (dim red, dim green, dim blue).  To change to color of a feature, enter
  the feature number, followed by a space and the color value.  For ex-
  ample, to change the color of non-sunlit land (feature 2) to brown,
  enter:
  2 gR
  and to change the color of sun-lit land (feature 10) to bright yellow
  enter:
  10 rgbRG
  You can experiment with different color values to produce the most
  pleasing effect.  CSET shows changes in the color palette as you enter
  them.
COLOR        Set color
  The COLOR command provides a way to change the GeoClock default colors.
  The format is:
  COLORnddbb
  where n is the feature number (0-7), dd is the color value for the non-
  sunlit feature, and bb is the color value for the sunlit feature (n+8).
  The easiest way to get the proper values is to use the CSET menu. The
  proper COLOR commands to produce the colors as modified by CSET are
  given on the right hand side of the CSET menu. For example, for the
  color values given in the CSET example, the command is COLOR22062.
ECOLOR       Set color for elevation maps
  The ECOLOR commands provides a way to change the colors used for
  elevation maps.  The format is the same as the COLOR command:
  ECOLORnddbb   These colors are not effected by CSET.
TEXTBG       Set text background color
  TEXTBGn    changes the text background color number to n.  The default
  value is 4.
MCOLOR       Set color for Distance cursors
  This command sets the colors of the Markers on the "D"istance screen. It
  may be required to improve the appearance of the cursors if the NOBLINK
  command was used.  The syntax is MCOLORxxyy. Marker 1 is set to color
  value xx, and Marker 2 is set to color value yy. For example, MCOLOR5961
  sets Marker 1 to 59 (bright cyan) and Marker 2 to 61 (bright magenta).
FCOLOR       Set map frame color
  FCOLORn  sets the color of the frame around the map display to n.  The
default value is 15 (white).  A value of 0 through 15 frames the map in
that color.  Any other value (for example, -1) does not display any frame.







 4.12 Zoom

    The Zoom function comes in two forms.  If you have a VGA or better
display and a mouse, the first form is always active and can be used at any
time.  The second form is activated by pressing the letter Z, and works on
all display types and is somewhat more precise.

  **** First Form ****
    If you position the cursor anywhere on the screen (except the icon bar)
and click the left mouse button, GeoClock will display the highest
resolution map containing the point under the cursor.  If you click the
right mouse button the next map in the hierarchy defined by the MAKEZOOM
program will be displayed.  If you click the left button while on a lowest
level map, or the right button while on the top level map, a short beep
will sound and the map display will not change.

  **** Second Form **** (registered users only)
    This function allows the user to change the map background using the
cursor.  A mouse or the arrow keys can be used.  To invoke the function,
press the letter Z.  The screen will be stabilize without any time or
sunlight information, and an Iron-Cross type cursor will appear.  Among
other things, the Zoom function can be used to identify all maps that
include a given location.
    Use the mouse and/or arrow keys to locate a position on the map.  (If
you hold the shift key down with the arrow keys, the cursor will move 8
times faster than non-shifted arrows.)  Each press of the right or left
button on the mouse, or CONTROL or ALTERNATE keys on the keyboard, will
switch to a new map containing that point.
    The left mouse button or CTRL selects the next smaller map containing
the point under the cursor (zooms in).  The right mouse button or ALT
selects the next larger map containing the point under the cursor (zooms
out).  The "Z" key switches to the smallest map (most detailed) containing
the point.  The cursor will remain at the specified latitude/longitude
during the switch.  When the desired map is displayed, press the middle
button or the ESCAPE key to return to time display.







 4.13 Distance Measurement

    The distance measurement function comes in two forms.  The first is
activated by pressing D or clicking the Distance icon, requires a mouse and
displays two points.  The second is activated by pressing the @ key,
displays three points and does not require a mouse.

  **** First Form ****
    Clicking on the distance icon, or pressing the letter D, activates the
two point distance function.  One pointed is fixed and the other is
controlled by the mouse.  Pressing a mouse button, or pressing ENTER, moves
the first point to the current mouse position.  At the bottom of the
screen, the coordinates of both points, the distance between them, and the
azimuths between them are displayed.  If the EPHEMERIS command (see) is set
to 1, the sun rise, sun set, sun azimuth, and sun elevation will be
displayed for the selected point (the red cursor, the one fixed by a mouse
click).  To exit the distance function, click on the reset icon in the
upper right, or press ESCAPE.

  **** Second Form ****
    This function provides a display of the coordinates of three selected
points, and the distances between them, as controlled by a mouse or the
keyboard.  The function is invoked by pressing the "@" (shift 2).  City
names remain on the map, and two text lines appear at the bottom of the
screen.  They indicate latitude and longitude of three points, and
distances between them.
    Point 3 is the current cursor position, which you can change with mouse
motion or the arrow keys.  (If you hold the shift key down with the arrow
keys, the cursor will move 8 times faster.)  Point 1 is selected by the
left mouse button or the CONTROL key on the keyboard.  Point 2 is selected
by the right mouse button or the ALTERNATE key.
   To maintain smooth cursor movement, the distance and coordinate displays
are updated only when the cursor is not moving.  By default, the display
shows distance (in km and miles) on the top line, and location (in
degrees/minutes/seconds) on the bottom.  By pressing "A", azimuth (in
degrees, first from A to B, then B to A) and distance (in km) will be
displayed.  "D" returns to distance only.  Pressing "." will display
locations in degrees and fractions, while "'" will return to DMS format.
 To return to the normal GeoClock display, press ESCAPE or the center mouse
button.







 4.14 Scripts

   Up to 10 scripts can be played by GeoClock.  Each script consists of
GeoClock command lines (including a map selection command) and optionally a
time (by default, 15 seconds).  At the end of the specified interval, the
next command line in the script is executed.
   One way to start a script is to press a number key (0 through 9).  The
corresponding script file is named GEOSCR0.DAT through GEOSRC9.DAT.
Another way to invoke a script is to use the command SCRIPTx, where x is
any number.  The corresponding script file is GEOSCRx.DAT.  If this command
is on the command line or in GECONFIG.DAT, that script is executed as soon
as GeoClock starts.  If not, and if GEOSCR0.DAT exists, it is executed
automatically when GeoClock is started. If the script encounters a REPEAT
command, the script restarts at the beginning of the file.  If the script
encounters a HALT command, GeoClock immediately stops and returns to DOS.
The script stops when the end of the script file is reached, or any key is
pressed.
  Example:
GEOSCR9.DAT contains:
MAP1  LINE30  SHOWLL
MAP2  LINE5
RANDOM  30  NOLINE
REPEAT

When 9 is pressed, MAP1 with LINE30 and SHOWLL is displayed for 15 seconds.
then MAP2 with LINE5 is displayed for 15 seconds, then a randomly selected
map is displayed for 30 seconds with NOLINE, and the sequence repeats.

Scripts can also be used as macro keys.  For example, if GEOSCR1.DAT
contains:
MAPP1

then when 1 is pressed, the next sequential map in map number sequence is
displayed.  If GEOSCR2.DAT contains:
T+0.0416666667

then when 2 is pressed, the current time is advanced by one hour (1/24
day).







 5.  Advanced Topics

These are topics of interest only to advanced users or are topics of
specialized interest.

 5.  Advanced Topics
 5.1  Configuring for Your Time Zone
 5.2  City Locations on Maps
 5.3  Configuring for Your City
 5.4  Finding Your Latitude and Longitude
 5.5  City Name Placement and Time Display
 5.6  Make Zoom utility
 5.7  Colors and Default Colors
 5.8  Changing GeoClock Defaults
 5.9  Calendars and Daylight Saving Time
 5.10 Ephemeris Data and Accuracy
 5.11 Software structure
 5.12 Map Generation System
 5.13 Elevation Maps



 5.1  Configuring for Your Time Zone

     GeoClock has a comprehensive system for handling all known time zones
in the world.  The GEOZONES.DAT file contains definitions of all time zones
and daylight saving time systems identified to date.  You can read or print
this file for the complete list.
     These definitions include the dates for switching between standard and
summer time (for example, 91/04/07 and 91/10/27 for most of the U.S. in
1991), the common names for standard and summer time (for example, EST and
EDT), and a codename to refer to the definition (for example, ET).
Ordinarily, you should not need to change these definitions.  Each time
zone is preceded by the keyword ZONE.
     To make sure that GeoClock gives the proper sun position, you must
tell GeoClock what time zone your PC's clock uses.  (For most users, this
will be the time zone in which you live.)  This is done by editing
GECONFIG.DAT (use TED if you do not have a favorite ASCII editor) and
adding the proper PCZONE command.  This command should be placed in the
GECONFIG.DAT file.  The format is:

PCZONE  codename

where codename is the codename for the time zone, as listed in the ZONE
commands.  There should be no other characters on this line.

    Some common codenames are:
ET      Eastern Standard/Daylight Time
EST     Eastern Standard Time all year (most of Indiana)
CT      Central Standard/Daylight Time
MT      Mountain Standard/Daylight Time
MST     Mountain Standard Time all year (Arizona)
PT      Pacific Standard/Daylight Time
AKT     Alaska
HST     Hawaii
UKT     United Kingdom, Ireland
+1A     Most of continental Europe
+2A     Eastern Europe
JST     Japan

    The GEOSETUP program will prompt you for the time zone code (or supply
it automatically if you live in a US zip code area) and place the time zone
code in the GECONFIG.DAT file.







 5.2  City Locations on Maps

    GeoClock has great flexibility in displaying cities on the maps.  For
most maps (e.g., MAP2) there is a corresponding text file (e.g., GEO2.DAT)
that contains the customization information for that map.  GEOCLOCK.DAT is
used for MAP1, and any other map that does not have a corresponding
GEOn.DAT file.
    The first line of any GEOn.DAT file is the time zone codename that
determines which time zone will be used for time display on that map.  For
example, ET indicates Eastern time, and CT indicates central time.  (See
"Configuring for Your Time Zone.")  This should normally be the time zone
codename for the first city listed (the second line of the file).  This
city is the "primary" city for the map.  The rest of the lines in the file
specify the names and locations of other cities to be displayed.
    The format for display of a city is   "Latitude Longitude Name".
Either decimal degrees or degrees minutes seconds (DMS) may be used.  In
the decimal degree format, the minus sign (-) indicates south latitude
(south of the equator) and west longitude (in the western hemisphere).  For
DMS format, separate entries by an "x", and place the direction indicator
at the end.  For example, 31 degrees 15 minutes west longitude would be
31x15W in DMS, and -31.25 in decimal, while 45 degrees 12 minutes 38
seconds north latitude would be 45x12x38N in DMS and 45.2106 in decimal.
Some examples of these lines are:

  34.00     -118.25   Los Angeles
  30x3N     31x15E    Cairo
  -26.17    28.03     Johannesburg
  27x49N    85x21E    Katmandu Nepal

    The first city listed in a file is the "primary" city.  It is used for
the astronomical calculations which are normally shown at the bottom of the
map.  The sunrise and sunset time, azimuth and elevation to the sun, local
time, and the sun's sub point (the point on earth where the sun is directly
overhead) can be displayed for this location.







 5.3  Configuring for Your City

    You will probably want to customize the display by entering cities of
your choice on some maps.  In particular, you may want to make the city
where you live the "primary" city on one or more of the maps.  This will
give sunrise and sunset, plus other sun-related data for your city on the
legend lines at the bottom of the each map.

   The simplest method is to use the GEOSETUP program.  This will add the
proper HTS command to GECONFIG.DAT.  The syntax for HTS is:

HTS/latitude/longitude/TimeZone/CityName.

For example:  HTS/41.98/-91.64/CT/Cedar_Rapids
places a marker and the name Cedar Rapids on every map where the city
appears, and gives sunrise, sunset, sun azimuth, sun elevation, and time
for Cedar Rapids at the bottom of all maps.  (The underscore _ is displayed
as a space.)  Alternatively, you can use HTA instead of HTS.  This uses
Cedar Rapids for the sunrise, etc., data, on all maps.  This command can be
added to the end of GECONFIG.DAT at the same time that the PCZONE command
is added, or included on the GEOCLK command line.
    An alternative and more flexible method is to install your city as the
primary city in only some GEO*.DAT files, (for example, GEO2.DAT).  You can
do this by editing the file at the DOS command line (e.g., TED GEO2.DAT).
You can use any ASCII text editor, but TED is especially easy and is
supplied with GeoClock (See section 1.6).  Using the cursor and editor
keys, replace the first line of the file, if necessary, so that the time
zone codename corresponds with your time zone.  Then position the cursor at
the end of the first line and press ENTER.  This will create a blank second
line.  Next, enter your latitude, longitude, and location name on the
second line.  Finally, press F7 to save these changes.  (See "City
Locations on Maps" (1.5) for details on entering the latitude/longitude
definitions for cities.)
     Repeat this for every map you want to change.  It is not necessary to
change all the files, or to use the same city in every file.
     For example, here is part of the GEO2.DAT file that comes with
GeoClock:
                    ET
     38.90   -77.03 Washington
     33.75   -84.38 Atlanta
     42.33   -71.08 Boston
     ....
     Suppose you live in Cedar Rapids, Iowa and want Cedar Rapids to appear
as the primary city on one or more maps.  The first step is to determine
your latitude and longitude (see "Finding Your Latitude and Longitude"
(1.7)).  Next, use the TED editor that came with GeoClock, or any other
text editor, to edit the GEOn.DAT file corresponding to the map file you
want to change.  For example, to change MAP2 (the US map), edit GEO2.DAT.
If you use TED, just enter TED GEO2.DAT.  Change the first line to your
time zone, if necessary.  Cedar Rapids is in the Central time zone, so use
the editor to change ET to CT.  Next, make Cedar Rapids the first city
listed.  In this case, it is 41.98N and 91.64W.  Adding this data to the
GEO2.DAT file gives:


                    CT
     41.98   -91.64 Cedar Rapids
     38.90   -77.03 Washington
     33.75   -84.38 Atlanta
     42.33   -71.08 Boston
     ....
    If you want Cedar Rapids to appear on a map, but do not want it as the
primary city, enter its latitude, longitude, and name in the list of cities
on the GEO*.DAT file, but not as the first city.







 5.4  Finding Your Latitude and Longitude

     Accurate lat/long are essential for proper display of cities on a map,
and also for accurate sunrise and sunset times of a map's "primary" city.
An error of one degree of longitude changes sunrise and sunset by four
minutes.  The easiest way to find a particular latitude and longitude is to
look it up in an atlas.  The next easiest way is to call your local airport
or weather bureau for the information.  You can also leave a request for
information on the GeoClock Bulletin Board, and you should get a reply in a
short time.







 5.5  City Name Placement and Time Display

     For registered users only, additional control over city placement,
color, size, and local time display is possible.  All are marked by
characters appearing after an exclamation point (!) on a city line in
GEOn.DAT.  This new data consists of an optional string of characters as
follows:

     A - show city name Above mark
     B - show city name Below mark
     L - show city name Left of mark
     R - show city name Right of mark
     Y - show city name in color 5 (Yellow by default)
     E - show city name in 8x14 font
     M - show city name in 8x8 font (default)
     S - show city name in 4x8 font
     T - show city name in 4x6 font
     X - show city name in external font (see FONTLOAD command)
number - show city name in color number (e.g., 6 shows city name in
         color 6).  Color numbers are described in "Color Control."
     N - show a name without a mark.  This is particularly useful if you
         want to name an area, such as the Pacific Ocean
     Z - indicates a country name rather than a city name
     O - display the last symbol defined (see SYMDEF) instead of the normal
         marker for the city.

     After these optional codes, the line may be followed by a space and a
time zone code.  If included, this specifies that the local time for that
city is to be displayed to the right of the city name.  If a "*" is
included, the name of the time zone will be displayed in addition to the
time.  THE SPACING OF THESE CHARACTERS IS CRITICAL.  For example:

                  ET
   38.90   -77.02  Washington !E
   42.65   -73.75  Albany !Y
   35.08  -106.65  Albuquerque ! *MT
   42.28   -83.75  Ann Arbor !A
   33.75   -84.39  Atlanta !0
   44.30   -69.76  Augusta
   33.52   -86.81  Birmingham ! CT
   46.80  -100.78  Bismarck !B6 *CT

     In this example, Washington will be displayed in the 8x14 font, Albany
will be displayed in yellow, Albuquerque will be followed by the local time
and MST or MDT as appropriate, Ann Arbor will appear above the marker,
Atlanta will be displayed in color 0 (red), Birmingham will appear follow
by local (central) time but without a CST or CDT, and Bismarck will be
displayed below the marker in color 6 (black) and followed by local time
and CST or CDT.







 5.6  Make Zoom utility


The MakeZoom utility allows the zoom-up sequence for the always active
mouse zoom to be defined.  Clicking the right button, or the zoom-up icon,
uses this take to find the next map up.  Initially, MAKEZOOM scans the map
directory and builds a candidate zoom up text file named GEOZOOMU.TXT.
This file has one line per map:
mapnumber  zoomoutmapnumber   mapname -> zoomoutmapname
Only the two numeric fields are processed, the rest is comment.  Then the
program makes the GEOZOOMU.BIN file, which GeoClock uses.  This file is
produced automatically when MAKEZOOM is run.  If desired, the GEOZOOMU.TXT
file can be edited to change the zoom sequence.  When MAKEZOOM is run, if
the GEOZOOMU.TXT file already exists, you are prompted to either use this
file, or produce a new one.  You should run this program every time you add
or delete a map.

You can use the MAKEZOOM utility for the windows version of GeoClock by:
MAKEZOOM W







 5.7  Colors and Default Colors

    The EGA graphics adapter provides for the simultaneous display of 16
colors from a palette of 64.  The VGA graphics adapter provides for the
simultaneous display of 16 colors from a palette of 262144.  Most programs
use the default palette, which roughly corresponds to the colors provided
by the CGA in text mode.  In order to make the map display the most at-
tractive, the EGA/VGA/SVGA version of GeoClock does not use this standard
palette.  Instead, the 16 colors that can be displayed simultaneously are
used to represent 16 features displayed by GeoClock. The first eight
numbers are for features not in sunlight, and the second eight are for
features that are in sunlight:
    The 16 color values are expressed by combinations of the following
letters:
       B  = bright blue              b = dim blue
       G  = bright green             g = dim green
       R  = bright red               r = dim red
  For example, white is rgbRGB (r+R=full red, g+G=full green, b+B=full
  blue), bright yellow is rgbRG (r+R=full red, g+G=full green, b=dim
  blue), and grey is rgb (dim red, dim green, dim blue).  These colors are
  also indicated with numerical values determined by the formula:

   Color value = 32*r + 16*g + 8*b + 4*R + 2*G +B

Default colors in GeoClock are as follows:

Feature      Use                  Color         rgbRGB   Color Value
  0    Political Bdy (dark)       red           ---R--      4
  1    Water (dark)               blue          -----B      1
  2    Land (dark)                dark green    -g----     16
  3    Land/Water Bdy (dark)      green         ----G-      2
  4    Text Background (dark)     black         ------      0
  5    Aux Text Color (dark)      yellow        rgbRG-     62
  6    Lat/Long Lines (dark)      black         ------      0
  7    Frame and Text             white         rgbRGB     63

  8    Political Bdy (light)      bright red    rgbR--     60
  9    Water (light)              light blue    --b--B      9
 10    Land (light)               green         ----G-      2
 11    Land/Water Bdy (light)     light green   -g---G-    18
 12    Text Background (light)    black         ------      0
 13    Aux Text and Sun (light)   yellow        rgbRG-     62
 14    Lat/Long Lines (light)     black         ------      0
 15    Frame and Text             white         rgbRGB     63

    The "rgbRGB" designators are used for changing display colors with the
CSET function.  The color values are used with the COLORnddbb command at
the [C]ommand line or in GECONFIG.DAT.
    In order to avoid an annoying "blinking" effect on every screen update,
it is desirable that there be identical colors for colors 4 and 12, and for
colors 7 and 15.







 5.8  Changing GeoClock Defaults

    There are at least four ways to change default values in GeoClock.
Most default values can be overridden for all operation by inserting
another command in the GECONFIG.DAT file.  This can be done with any text
editor.  For example, MARK, CITY, and LINEnn commands are often added to
the GECONFIG.DAT file.  Some users also add their favorite map at the end,
so it (rather than Map 1) comes up automatically for display on initiating
the program.
    The second way to change default values is by adding commands as para-
meters when executing GeoClock (usually by typing GEOCLK at the DOS command
line).  The third way is through the normal [C]ommand process.
    The fourth is by adding commands in map data files (GEO*.DAT).  With
this method, you should be aware of which commands will apply only to a
given map, and which ones will change all map displays until a contrary
command is issued.
    Some commands in GeoClock are "global," while others are "non-global."
Global commands remain in effect until they are countermanded with a
contrary command, or the program is terminated.  Non-global commands lose
their effect once the user changes maps.  Most commands regarding map
display, map annotation, time control, the terminator, and twilight are
global.  INCLUDE, DRAWLINE, and daylight/darkness commands (NORMAL, LIGHT,
etc.) are non-global.







 5.9  Calendars and Daylight Saving Time

   Time zones are not built into the GeoClock program.  Rather, they are
defined in the GEOZONES.DAT file.  These definitions are for the current
year, and are usually updated at least twice a year.
   Time can be specified for individual locations by entries in GEO*.DAT
files.  (See "City Name Placement and Time Display.")
   In the abstract, time is an immutable commodity.  However, its measure-
ment and legal specification are constantly changing.  Time zones, daylight
saving time, and even the calendar itself have changed from year to year or
century to century.  Some important factors in the measurement of legal
time (which is what GeoClock shows) are discussed below.

   Great Britain adopted Greenwich Mean Time as the first standard time by
act of Parliament in 1880.  The four standard time zones were adopted in
the U.S. in 1883.  The Meridian Conference, held in Washington in 1884,
established the Greenwich (near London) as the reference point for world-
wide longitude measurements, and for the general scheme of time zones.
    Some countries have switched from one time zones to another by law
(e.g., Latvia).  Also, time zone boundaries have been moved within coun-
tries (e.g., Russia), and portions of some countries have been assigned to
different time zones (e.g., western Ohio).  Thus, if you specify dates in
past years, times shown GeoClock are not always correct.
    GeoClock will display "standard" times for dates prior to 1884, But
they obviously do not correspond to actual time measurements which were
used then.  These were usually based on local sun time.

    Daylight saving time is a special case.  Much of the U.S. has observed
DST since World War II, and a uniform set of dates was specified in 1967.
The DST period (now in all states except Arizona, Hawaii, and part of
Indiana) has been from early April to late October since 1987.  All con-
tinental European countries have observed summer time from late March to
late September since 1980 or 1981, and some have done so for several
decades.  Great Britain and Ireland have summer time from late March to
late October.
    The DST command allows daylight saving time to be used under the cur-
rent set of specifications for a period of years selected by the user.
(See "Time Control and Display.")  The default period is back to 1980 and
indefinitely into the future.  However, there does not seem to be any
practical way of selectively recognizing individual countries' different
summer time patterns in the past, or in the future.  For example, GeoClock
(with GEOZONES.DAT set for current time patterns) will not correctly show
times in 1979, when France observed summer time but Germany did not.

    The SHOWDAY function in GeoClock gives days of the week accurately back
to the year 100 AD.  It uses the Julian calendar up to October 4, 1582, and
the Gregorian calendar from October 15, 1582 on.
    An error of less than one day in 100 years caused the Julian calendar
to diverge from accepted benchmarks.  By the 16th century, the vernal
equinox occurred around March 11, rather than March 21.
    Pope Gregory XIII promulgated the "new style" calendar in 1582.
Thursday, October 4, 1582 was followed by Friday, October 15.  Catholic
countries adopted the Gregorian calendar immediately, or within a few
years.  Most Protestant countries on the Continent adopted the new calendar
around 1700.  England and the American colonies changed in 1752, by act of
Parliament.  Thus, days of the week shown by GeoClock for events in England
and America between 1582 and 1752 are generally incorrect.
    Orthodox Christian countries adopted the Gregorian calendar later.
Russia was the last European country to do so, after the communist revo-
lution of 1917.  As a result, the USSR celebrates the October Revolution
(October 25, 1917 in the "old style" calendar) on November 7.







 5.10 Ephemeris Data and Accuracy

     The ephemeris data in GeoClock is calculated using formulas from
"Astronomical Formulae for Calculators" (Jean Meeus, Willmann-Bell Inc,
Richmond VA).  They were calibrated by comparing with data from
"Interactive Computer Ephemeris" (ICE) (Nautical Almanac Office, Code FA,
US Naval Observatory, Washington, DC 20392).  For a period of 400 days
including 1991, the maximum and RMS latitude errors are 0.0047383 and
0.0019377 degrees, while the maximum and RMS longitude errors are 0.0131104
and 0.0053660 degrees.  This accuracy is approximately four times better
than the method used in GeoClock 4.2 and earlier, and should provide better
accuracy for past and future years.
     The terminator is shown as the locations where the sun's center is a
specified angle above the horizon, ignoring atmospheric effects.  For the
default value of 0 degrees, the sunrise occurs earlier and the sunset
occurs later than the terminator indicates.  The sun rise and sun set times
are also computed as the times that the sun's center is a specified angle
above or below the horizon.  The default value, -0.8333, corresponds to the
normal definition of sun rise and set (as printed in newspapers and
almanacs), where the visible top edge of the sun just breaks the horizon.







 5.11 Software structure

     GeoClock is written entirely in Turbo Pascal version 5.0, except for
the mouse interface routines and a few inline sections required for speed.
It has approximately 14000 lines of source code. It uses 8 byte reals for
most calculations, and thus relies on the 80x87 emulation package for
systems without a math co-processor. It uses a custom graphics package
which provides access to special hardware features (such as independent
control of screen planes, fast fill, and preserving the graphics memory
during text display) that are not available in the EGAVGA.BGI driver.







 5.12 Map Generation System

     The maps used for the GeoClock program were produced by a custom data
base and software system. This system consists of a highly compressed
vectorized map data base and a set of programs to convert the data into
custom maps. The data bases are used. The primary data base is a PC
conversion of World Data Bank II. It contains approximately 5.7 million
vectors covering coastlines, islands, lakes, rivers, and similar geologic
features, together with political boundary data. It covers the entire
earth, and included features are accurate to approximately 600 meters.
World Data Bank II was converted to this custom PC format by an ad hoc
program which took advantage of specific features of both data bases. In
its operational form, the PC data base uses approximately 0.84 bytes per
vector, and in archival form takes approximately 0.5 bytes per vector. The
data base is therefore easily stored and manipulated on an AT class PC.

A secondary data base is a PC conversion of 1979 1:2 Million Digital Line
Graph data base from USGS.  It includes highway and railroad data in
addition to much more detailed physical and political features, and
contains about 8.3 million vectors covering the 50 states, compressed to
about 13 MB (1.6 bytes per record) on the PC.

A third data base is a PC conversion of the 1992 "Digital Chart of the
World", made by digitizing 1:1 Million ONC charts (and some other paper
sources).  The extracted the data (highway, railroad, coastlines, islands,
lakes, rivers, and streams) contains about 30 million vectors and
compressed to about 50 MB on the PC.

A graphics tablet and several custom programs are used to add features than
were not contained in the original data bases, for example, the borders of
the countries of the former USSR.

     Custom maps are generated by using two programs. The first, MAPGEN,
reads the appropriate parts of the map data base and produces separation
files of the required feature data as EGA, VGA, or 800x600 raster images.
Rectangular, polar, orthoscopic, azimuthal-equidistant, and Lambert
projections may be used in forming these separation files. Depending on
complexity and scale, this process takes between 30 and 300 seconds on an
AT with a co-processor. The second, MOVIE, allows the user to process the
separation files to select the features and colors for the final map,
including filling areas. This program also writes the map in a rasterized
compressed format with headers and trailers so that it may be easily used
as background data for other programs (for example, the GeoClock program).

     Both these programs, and the converted data bases, are proprietary and
not yet available to the general public. World Data Bank II is available
from National Technical Information Center, Springfield, VA, for about
$1000 on 5 reels of tape.  Both the 1;2,000,000 DLG data base ($30 on one
CD-ROM) and the Digital Chart of the World ($200 on 4 CD-ROMs) are
available from the US Geological Survey (Earth Science Information Center)
in Reston VA.







 5.13 Elevation Maps


  GeoClock supports color-coded elevation maps.  Since these maps use
color in a radically different way that normal GeoClock maps, several
commands are required to give good map display, and some GeoClock features
do not work, or work poorly, on these maps.  Very few such maps are
available, and they are available on from the GeoClock BBS.
  The ECOLOR command sets the colors for elevation maps.  While there is a
built-in palette for elevation maps, it is highly recommended that ECOLOR
statements be included in the GEOn.DAT files for these maps.
  Elevation maps use palette positions that correspond to the sunlit area
on normal maps.  Thus, the sunlight pattern cannot be displayed on
elevation maps.  The BLANK statement should be included in the GEOn.DAT to
avoid display problems.  Carefully designed elevation maps and palettes may
support sunlight display.
  For the same reason, the colors for annotation may be different between
elevation maps and normal maps.  Also, the normal lat/long line drawing
system, that overwrites only water and land, and not edges and political
borders, does not work with elevation maps.  An LLCOLOR command is required
to prevent color corruption on these maps.  Also, the icon display, and the
distance function, will be distorted (the "advanced" distance function,
activated by pressing @ (shift-2) works correctly but does have distorted
colors).
  The GEOn.DAT files distributed with new elevation maps will properly
handle all these factors.









 6.  Utilities and GeoGlobe

  GeoClock includes a number of utility programs, and the GeoGlobe spinning
Globe Program

 6.  Utilities and GeoGlobe
 6.1  GeoGlobe     Spinning Globe program
 6.2  GeoSetup     Customize GeoClock
 6.3  MakeZoom     Rebuild zoom tables
 6.4  XXGeoDat     Delete unnecessary GEOn.DAT files
 6.5  GeoNoDup     Delete unnecessary MAPn.EGA files
 6.6  SunData



 6.1  GeoGlobe     Spinning Globe program

   GeoGlobe is an optional program which displays a very smoothing
revolving globe on a VGA screen.  It shows the sunlight curve, and the
globe revolves around the center of the screen as the earth revolves around
the sun.  It uses several advanced techniques to ensure smooth operation,
and provides 60 or 72 frames per second animation (in contrast to 30 fps
for TV, 24 fps for movies, and 15 fps for multimedia displays).
   The program is started by entering  GEOGLOBE  at the DOS command line or
by clicking the GeoGlobe icon while GeoClock (GEOCLK.COM) is running.  It
is stopped by pressing any key.
   GeoGlobe runs best if you have at least 1.3 MB of free RAM (any
combination of low RAM, EMS, and XMS).  If you do not have this much free
memory, GeoGlobe will be forced to read some data from the disk on each
revolution. If you have a large enough disk cache, this may be acceptable.
If the disk light comes on after several revolutions of the globe, you do
not have enough memory to provide the best GeoGlobe performance.

Here are all the options available on GeoGlobe:
R  Do not load data into conventional RAM
E  Do not load data into expanded (LIM) memory
X  Do not load data into extended (HIMEM) memory
P  Preload the globe data before starting display
D  Always retrieve globe data from the disk
W  Do not "walk" the globe
All the above work WITHOUT a leading /

The following options require a leading / and usually need a parameter:
/Dn     Wait n milliseconds between frame display.  This is the minimum
     wait, and may be longer if the refresh rate of the monitor does not
     divide n, or if it takes longer to read and process the frame.  You
  may have to use this parameter under OS/2 2.x or windows 3.x in the
386 mode, because of the way the screen refresh is emulated on these
systems.
/Wfile  Read the walk data from named file (default is the internal
     table give an eliptical walk)
/Wyyyxxx  Show a fixed globe yyy pixels up from the lower right corner,
     and xxx pixels left from the lower right corner.
/Cxxbbgg  Use palette numbers (same as used in CSET) xx for background,
     bb for blue (ocean) and gg for green (land).
/L  -  does NOT display the sunlight curve
/Lbbgg - displays the sunlight curve, using color bb for water in shade,
and  gg for land in shade.  The sunlit colors are still set by /C
/Kn - performs one walk step every n globe frames.  n=105 gives approximate
      synchronization between the day and the year.  On a fast computer,
      GEOGLOBE /K105 gives one complete revolution around the screen in
      about 36.5 minutes, with each day taking about 6 seconds.
/T - Show approximate date
/X - Show rotation axis
/B - starts the globe at a random position
/Bmmdd - starts the globe at approximately date month mm, day dd.  The
actual starting point may be off by a day or two.

The options are used on the GeoGlobe command line (for example,
GEOGLOBE /T /X ) when GeoGlobe is started directly from DOS, or via the
WCGLOBE command (for example   WCGLOBE /T /X  in GECONFIG.DAT) when
GeoGlobe is execute from GeoClock.

GEOGLOBE.DOC has more detailed documentation on GeoGlobe and its files.







 6.2  GeoSetup     Customize GeoClock


   The GEOSETUP program performs all the necessary initial customization of
GeoClock for your location.  It sets up time zone and primary city data,
and sets GeoClock for EGA, VGA, or SVGA operation.  Start GEOSETUP by
typing GEOSETUP at the DOS command line.
   GEOSETUP tries to detect the type of video card you have.  If you have a
VESA compliant SVGA (800x600x16), GEOSETUP will optionally test the card by
producing a 800x600x16 display.  If the display is correct, GEOSETUP will
customize GeoClock for SVGA display.
   If you have a US zip code (other than APO or FPO addresses), GEOSETUP
will automatically supply the proper time zone and latitude/longitude
information.  All you need to do is enter your zip code and city name when
prompted.  If you do not have a US zip code, you can select a city from the
list displayed.  Pressing a letter key will advance the cursor to the
countries starting with that letter, the PageUp and PageDown keys move to
the next country, and the arrow keys allow you to move through the list one
at a time.  Press ENTER when you have found your city, or a city close to
your city.  In either case, you must specify whether you have an EGA or VGA
or SVGA based display.  With this information, GEOSETUP builds an initial
GECONFIG.DAT.







 6.3  MakeZoom     Rebuild zoom tables


The MakeZoom utility allows the zoom-up sequence for the always active
mouse zoom to be defined.  Clicking the right button, or the zoom-up icon,
uses this take to find the next map up.  Initially, MAKEZOOM scans the map
directory and builds a candidate zoom up text file named GEOZOOMU.TXT.
This file has one line per map:
mapnumber  zoomoutmapnumber   mapname -> zoomoutmapname
Only the two numeric fields are processed, the rest is comment.  Then the
program makes the GEOZOOMU.BIN file, which GeoClock uses.  This file is
produced automatically when MAKEZOOM is run.  If desired, the GEOZOOMU.TXT
file can be edited to change the zoom sequence.  When MAKEZOOM is run, if
the GEOZOOMU.TXT file already exists, you are prompted to either use this
file, or produce a new one.  You should run this program every time you add
or delete a map.

MAPZOOM go    runs the program automatically, rebuilding the text file and
selecting the highest resolution world map as the top of the heirarchy.

MAKEZOOM W    runs the program for the Windows version of GeoClock







 6.4  XXGeoDat     Delete unnecessary GEOn.DAT files


  This program scans the current directory and delete all GEOn.DAT files
which do not have a corresponding MAPn.EGA file.







 6.5  GeoNoDup     Delete unnecessary MAPn.EGA files


GEONODUP allows you to eliminate duplicate GeoClock maps and data files.
If you have several identical maps, except for resolution and perhaps
features displayed, this program will identify them and allow you to check
and delete the unneeded maps.  For example, it will show MAP6002 and MAP2
as duplicates.  The algorithm used may identify non-duplicate maps as
duplicates (for example, old format elevation maps), so you should display
the maps using the "D" function before you delete them.

This program searches the current directory for possible duplicate maps
When potential duplicates are found, a list all the maps, their names,
and resolution are given.  The user can delete any of the maps, or view the
maps, or continue the   search.  Maps selected for deletion are renamed to
.OLD or .nnn .  After the user verifies that the renamed maps are indeed to
be deleted,   DEL *.OLD  will remove them from the directory permanently.
After this program is run, you should rerun MAKEZOOM.

GEONODUP  go   will run the program without interaction and will delete
files automatically.







 6.6  SunData


SunData computes the sun rise and set, and twilight begin and end, for any
place on earth for any date after 100 CE.  It requires the files
distributed with GeoClock 6.0 or later (GEOCLK6?.ZIP or GEOCLK7?.ZIP)

To run SunData, enter  SUNDATA at the DOS command line.  The program first
allows you to select a city using the GeoClock Gazetteer.  If the city or
location of interest in not in the list, and you know the latitude and
longitude of the location, select a close by location *in the same time
zone*.

Next, press Y confirm the data, or N to change the city name, lat/long, or
sunlight and twilight definition angles.

Next, enter the start date in yy mm dd format (for example, 1995 Feb 10 is
95 02 10).  For dates before 1950 or after 2049, you must use the yyyy form
(i.e., 1582 10 01).  mm dd  gives the current year, while dd gives the
current month and year.

Finally, enter the end date (in the same format except dd is not allowed),
or a single number to get that number of consecutive days.

The program will list the date and day of week, the times of sun rise and
sun set, the times of morning twilight begin and evening twilight end, and
the local time zone name, for each date selected.

See the documentation with GeoClock for details on how to operate the city
selection system and about the algorithms used.  The optional [output file]
parameter on the SunData command line causes SunData to write the output to
the named file in addition to the screen.

SunData is offered without charge, but it does require the files from
GeoClock.  GeoClock is offered as shareware, which means that if you use
and enjoy the GeoClock program, you must register it.  See the
documentation and MAILER file with GeoClock for more information.







 7.  HAM package

  The HAM package is an add-in to the registered version of GeoClock.  It
supports a variety of features to support HAM, SWL, and DX operators, and
includes a custom Equidistant-Azimuthal (Great Circle) projection map
centered on your location.

 7.  HAM package
 7.1  HAM package features
 7.2  Starting the HAM package
 7.3  HAM CD-ROM
 7.4  Call Sign Analysis
 7.5  Use of other GeoClock features
 7.6  Twilight zone definition
 7.7  HAM data base
 7.8  Support
 7.9  Call Sign Analysis Algorithm



 7.1  HAM package features

  The GeoClock HAM package activates several new features of particular
interest to amateur radio operators and short-wave listeners. These
include:

Azimuthal-Equidistant (Great Circle) maps.

Day, night, and twilight zone display:
- Twilight zone parameters can be set to indicate boundaries of sun
  illumination on the F- and D-layers of the ionosphere.

Amateur radio call sign analysis (based on a user-maintainable call sign
data base).  When a call sign (or prefix) is entered, the following
information is displayed:
- Remote station location
- short and long great circle path
- short and long path azimuth and range
- remote station (reciprocal) azimuth
- UTC, local, and remote station local time
- DXCC and WAE country identifications
- CQ and ITU zones
- Continent, area, and location names

  The package has three major components: a custom Azimuthal-Equidistant
map centered on your station; a call sign data base, and a utility program
to process the text call sign data base into the GeoClock form. Your
registered copy of GeoClock will use this data base to overlay HAM data on
the custom map.

   The custom Azi-Equi map centered on your location is named MAP9009.EGA.
A custom GEO9009.DAT file is also provided to control the display of HAM
data.

   If the optional QRZ or Buckmaster HamCall (April 95 and earlier) CDROM
is online, the GeoClock HAM package will use the CDROM to provide very
accurate coordinates and headings for US call signs in the data base.

   These features are provided in addition to the other features of
GeoClock.







 7.2  Starting the HAM package

   To start the HAM package, enter "GEOCLK MAP9009" at the DOS prompt.
The program will start with your custom map and an indication of the sun
and terminator locations.  In the present release, ham features are
activated only on the custom map.

   TIP:  Edit your GECONFIG.DAT file with an ASCII text file editor and
add the command "MAP 9009" as the last line of this file.  You will now be
able to start the GeoClock program by simply entering GEOCLK at the DOS
prompt.  GeoClock will then start up automatically with your custom map
displayed.

  You should see a color Equi-Azi map displayed on your screen against a
black background.  Your location at the center of the map is shown with a
cross symbol.  Around the edge of the map are tick marks for every 10
degrees of azimuth.  In the bottom right corner, your name, call sign, and
location will be displayed.  In the bottom left corner two clock lines will
be displayed: GMT clock and local time at your location.  The format of
clock information can be tailored to suit your taste in clock style.  See
the "commands" section of the help system.

  In a few seconds (depending on the speed of your computer), the current
sunlight, night, and twilight zones will be displayed.  A yellow "sun" will
appear at the current sun subpoint (i.e., the spot on Earth where the sun
is currently directly overhead).  GeoClock will continue to adjust the
display to keep up with real time, at a rate dictated by the processing
power of your computer.  The date/time of the present display is shown on
the clocks in the lower left corner.

  Note: The rate of updates can be slower (approximately half as fast for
the worst case) whenever the boundaries of the twilight zone approach the
edges of the Equi-Azi map.  This is because a larger number of calculations
are required in order to accurately display the twilight zone boundary
around the map edge. GeoClock automatically adjusts to this condition in
order to insure that the map display remains accurate.







 7.3  HAM CD-ROM

   If your computer has a CD-ROM drive, and the QRZ or Buckmaster HamCall
(April 95 and earlier) CDROM is on line, GeoClock can use the database on
the CD-ROM to provide very accurate locations (within a few km) and bearing
for US call signs in the Data Base.  In addition, the name and home town of
the owner of the call sign is displayed when the call sign is keyed in.
This feature is activated automatically if the  HAMCD  command is in
GECONFIG.DAT.  If the CD-ROM drive is on a network or otherwise non-
standard, that command can be used to specify the exact path and file name
of the data base.

IMPORTANT: Starting with the October 1995 issue, the BuckMaster CD-ROM is
not compatible with GeoClock because the publisher deleted the file that
GeoClock uses.

You can obtain the QRZ CDROM at retail, or directly from the publisher:

QRZ Ham Radio CDROM
Walnut Creek CDROM
1547 Palos Verdes Mall, #260
Walnut Creek  CA  94596
Voice: 800-786-9907 or 510-674-0783
FAX: [phone]
Internet:  [e-mail]







 7.4  Call Sign Analysis

   To activate call sign analysis, simply begin to type in the letters and
numbers of the amateur radio call sign of interest.  When the first key is
depressed, a window pops open and the call sign you are typing is displayed
in the window.  Backspace and cursor keys may be used to correct any typing
errors.  When the call sign has been completely entered, press the RETURN
key.

  To abort call sign entry, press the ESCape key.  To clear the call sign
display, press any letter, then BACKSPACE and RETURN.

  You do not need to enter an entire call sign.  GeoClock will operate on
call sign prefixes.  However, GeoClock contains over 1,700 entries in its
call sign analysis database.  By entering a complete call sign, you will
frequently benefit from more precise location information.

  Call signs containing "/" may be entered directly from the keyboard;
e.g., FR5ZD/E, KN3T/KH6, HB0/DL7FT and SP9PBE/6.

  Once a call sign has been entered, GeoClock displays the following
information:
  a.   a cross "mark" at the location of the station is added to the map.
The location chosen is the most accurate location known to the database.
  b.   the local time at that distance location is added to the bottom
left corner of the screen.  This is the third clock time, labelled "mark:".
This time is continually updated, along with all the other clocks on the
screen.  Rules for local daylight savings (summer) time are applied.
  c.   short and long great circle paths from your location to the
distance "mark" are displayed on the map.  If you look carefully, you will
see the long path has a yellow color.  (On an Equi-Az map, the long path is
obvious: it is the path which crosses the edge of the map.)  In addition,
the left side of the screen shows the following for both short and long
paths:
  -- azimuth (direction) from your location to the mark.
  -- azimuth from the mark to your location.
  -- distance in miles and kilometers.
  d.   on the left side of the screen, additional information about the
call sign is shown:
  -- DXCC country: standard prefix and country name.
  -- WAE country: standard prefix and country name.
  -- area: state, region, or ooblast within the country for this
particular call sign.  For USSR ooblasts, the ooblast number is also shown.
  -- mark: the city or geographical spot which is displayed on the map and
used for distance and bearing calculations.
  -- CQ zone(s) for the area named above.
  -- ITU zone(s) for the area named above.

  To erase the information, press the minus (-) key.







 7.5  Use of other GeoClock features

  Most of the GeoClock commands and features described in the other
sections of HELP are available while using the HAM package. In addition to
real time operation, GeoClock can be instructed to operate at other dates
and times, and to operate at accelerated rates.  Distances and great circle
directions can be determined between any locations on the globe.  There are
many commands which allow you to customize the type and style of
information displayed on GeoClock.  You should take time to read the
remaining GeoClock help sections to learn about these additional
capabilities.  These will help you get the most out of your GeoClock
system.

   GeoClock also includes many additional maps of the world, polar regions,
continents, oceans, and individual countries.  These additional maps allow
you to zoom in on specific areas on interest in the globe; e.g., twilight
zone crossings of Africa, etc.

  While using your custom map and ham features, you can enter these other
GeoClock commands by holding down the SHIFT key while pressing the
appropriate letter.  For example, pressing SHIFT and T (for Time) allows
you to change the date/time used to calculate the displayed day, night, and
twilight zones.

  Note:  The SHIFT key must be used.  The CAPS LOCK key and caps-lock
status is ignored.  Any keys pressed without the SHIFT will be interpreted
as characters for a call sign.

  GeoClock supports two commands which are specific to ham features.
The HAMDB command specifies the name of the call sign database to be used.
This command should be in the GECONFIG.DAT file. For example,HAMDB HAM.HDB
specifies that HAM.HDB contains the call sign data base.  This database
MUST be in the format produced by GENHAMDB, not in text format.  Only the
first use of HAMDB in a given run has effect - the data base cannot be
changed while GeoClock is executing.

  The second command, HAM, specifies that the HAM features are to be
activated.  The best place to this command is in the GEO9009.DAT file
corresponding to your Azimuthal-Equidistant (Azi-Equi) map.  In the current
release of GeoClock, the HAM features may only be used when the Azi-Equi
map is displayed.  NOHAM deactivates the HAM features.







 7.6  Twilight zone definition

  One of the strengths of GeoClock is the ability for you to use the
TWILIGHT and SUNLIGHT commands to determine the boundaries of the day zone,
twilight zone, and night zone. You can set these boundaries to any value
desired.

  The value is the offset, in degrees, of the zone boundary from the edge
of the (geometric) sunlight part of the earth.  Typical values of interest
for shortwave operating include:

SUNLIGHT   -6.596       Boundary where sun starts/stops illuminating the
                        D-layer.  This controls absorption on the lower
                        frequency shortwave radio bands.
TWILIGHT   -14.165      Boundary where sun starts/stops illuminating the
                        F-layer. These values are based on average D- and
                        F-layer heights.  They define the Ionospheric Gray
                        Line: a twilight zone where shortwave radio signals
                        can pass through the D-layer without absorption.
                        Within this zone signals will encounter an illuminated
                        F- layer whose ionization level will be normally
                        enhanced over that found in the night zone.

Other common values for these commands include:

SUNLIGHT   -0.833       Sunset/sunrise at sea level, taking into account the
                        bending of light through the Earth's atmosphere and
                        the apparent width of the sun.
TWILIGHT   -6           Boundary of civil (legal) twilight, where it is bright
                        enough to work outdoors.
TWILIGHT   -12          Boundary of nautical twilight, where it is bright
                        enough to see the horizon.  One can take navigational
                        sightings with a sextant in this zone.
TWILIGHT   -18          Boundary of astronomical twilight, where sunlight on
                        the upper atmosphere interferes with the use of
                        telescopes by astronomers.
  To use the same values for twilight definition on all maps, enter these
commands in the GECONFIG.DAT file.  To specify values for each particular
map, the commands should appear in the GEO*.DAT file (where "*" represents
the map number; e.g., GEO9009.DAT for your custom Equi-Az map).







 7.7  HAM data base

  Analysis of amateur radio call signs is driven by information contained
in the ham database.  The database consists of three files:
  -- HAM42B.DAT:  An ASCII text file containing information described
below.  The "42B" in the name indicates the version number of the database:
"42" indicates that this database was prepared to support GeoClock version
4.2, and "B" indicates this is the second release of the database for this
GeoClock version.  You may have received a more recent version number.
  -- GENHAMDB.EXE:  An executable utility which converts the ASCII text
file into a binary format used by GeoClock for call sign analysis. Database
validation is also performed by this utility.
  -- HAM.HDB:  The binary format produced by the GENHAMDB.EXE utility
program.

               HAM42B.DAT

   The text form of the call sign data base consists of lines specifying
key data about a group of call signs. Each line consists of 11 data items:

1. CallPattern - the leading characters of the call sign group. For
example, PY signifies all call signs beginning with the characters PY.

  Wildcard characters are used in describing call sign patterns as follows:
  # -- represents any single digit; i.e., 0, 1, 2, ... 9.
  @ -- represents any single alphabetic character; i.e., A, B, ... Z.
  ? -- represents any single character, either alphabetic or numeric.
  * -- represents any string of characters.

  For example, PY#Z* represents any call sign beginning with PY, followed
by any single digit, then the letter Z, and then anything else. PY0ZZ would
match this pattern.

  All characters are interpreted as upper case.  This file has been created
in lower case.  If you add entries of your own, you may wish to make them
upper case so that you can easily recognize your own additions for future
maintenance and debugging purposes.

2. HamLat - the latitude of the location corresponding to this call sign.
This may be in decimal degrees (-15.146 for 15.146 degrees South), or in
degrees/minutes/seconds ("15 8 45.6S"). If the latter format is used, the
latitude must be enclosed in quote marks.

3. HamLong - the longitude of the location corresponding to this call sign.
This may be in decimal degrees (-15.146 for 15.146 degrees West), or in
degrees/minutes/seconds ("15 8 45.6W"). If the latter format is used, the
latitude must be enclosed in quote marks.

4. HamTimeZone - the time zone code for local time for this call sign
group.  For example, ET stands for US Eastern time.   The time zone
acronyms are defined in the GEOZONES.DAT file.

5. HamCQzone - the CQ zone for this call sign group. If the zone has
imbedded spaces, it must be enclosed in quotes; e.g., "3 4 5".

6. HamITUzone - the ITU zone for this call sign group. If the zone has
imbedded spaces, it must be enclosed in quotes.

7. HamContinent - the continent for this call sign group. NA, SA, AF, EU,
AS, AN, and OC may be used as abbreviations.

8. DXCCprefix - the standard DXCC call sign prefix designation for this
CallPattern.  The DXCC country identification for this CallPattern is
determined by this prefix.

9. AreaName - the name of the area within a country which is covered by
this CallPattern; e.g., state, ooblast, region, or other political
subdivision.  This must be enclosed by quotes.

10. MarkName - the name of the specific place used to represent this call
sign group. Ordinarily this should correspond to the latitude,
longitude,and time zone specified above. If the MarkName is missing,the
Areaname is used.  This must be enclosed by quotes.

11. WAEprefix - the standard WAE call sign prefix designation for this
CallPattern.  The WAE country identification for this CallPattern is
determined by this prefix.  If omitted, it is assumed that the WAE country
is the same as the DXCC country.

NOTE -- Items enclosed in quotes must be separated from one another by at
least one space.  All items must be contained on a single line.

   Another type of line in the text call sign data base specifies
equivalences in call signs. For example, ZY* =PY* specifies that any call
sign starting with ZY should be treated as if it started with PY; i.e.,
ZY5EG can be processed as if the call was PY5EG.

  Through appropriate combinations of "equates" and wildcards, the database
and analysis algorithm is capable of accurately determining the location of
any call sign heard on the air, including special prefixes.

  Mobile call signs (K3NA/MM, for instance) will be processed but not
result in a location display on the map, since the exact location of the
station is not predictable in advance.

  You may add additional entries to the HAM42B.DAT (or later versions) file
with a simple ASCII file editor, following the conventions outlined above.

  Any line beginning with a space in column 1 is interpreted as a comment.
You can see a typical comment line in the first line of the HAM42B.DAT
file, where columns are named for your convenience.

          GENHAMDB

  After the HAM42B.DAT file has been modified, it must be converted into a
format which can be processed by the GeoClock program.  The program
GENHAMDB.EXE does this conversion.  To start the program, enter at the DOS
prompt:  GENHAMDB (filename).  Example: GENHAMDB HAM42B.DAT

  Conversion processing can take several minutes, depending on the speed of
your computer.  The GENHAMDB utility provides you with a cryptic status of
the current state of the conversion process.

  When conversion is completed, GENHAMDB prompts you for a name for the
converted file.  The normal convention is to use the name HAM.HDB.  If you
do not specify a name, GENHAMDB will assume HAM.HDB.

NOTE -- GeoClock is initially configured to look for the database under the
name HAM.HDB.  To change this, you must modify the GEO9009.DAT file with an
ASCII file editor.  The command line HAMDB specifies the name of the .HDB
file to use when your custom map is displayed.  For simplicity, you may
wish to always tell GENHAMDB to name its output as HAM.HDB.

  After writing the .HDB file to disk, GENHAMDB allows you to test the
database without running GeoClock.  You will be prompted for a call sign.
GENHAMDB takes the call sign given and looks it up in the data base, and
displays the data base entry, including a summary of the equivalences used
in the analysis.  You can test as many call signs as you wish before
exiting the program.

  Note -- You will also see other numbers displayed along with the data
base entry.  These other numbers are used by the GeoClock software
developers in order to debug errors.

  To exit GENHAMDB, enter an empty call sign (i.e., just press the RETURN
key).

  If you wish to conduct further tests on the HAM.HDB file, simple re-enter
GENHAMDB by typing the following command at the DOS prompt:
     GENHAMDB HAM.HDB /D
where "HAM.HDB" is the name of the .HDB binary file to be tested. GENHAMDB
takes note of the "/D" debug switch on the command line, skips the database
construction phase, and prompts you to enter test call signs.







 7.8  Support

   The call sign data base included with the HAM version of GeoClock was
developed by Eric Scace, K3NA.  This is also a copyrighted software
product.  You may use the database for any other software which you have
developed for your personal use (e.g., contesting software, QSL card
processing programs, etc).  However, the database can not be incorporated
into any software product which is sold or distributed as shareware without
prior permission.

   Questions, comments, additional data and corrections to the ham database
are welcomed!  These can be sent to Eric via the GeoClock RBBS, or by other
means to:

  Eric L. Scace  K3NA
  10701 Five Forks Road
  Frederick MD  21701

  home:  [phone]
  work:  [phone]
  fax:   [phone]
  telex: [phone]  ERIC UC
  X400 e-mail:  C:USA  A:Telemail  O:Sprintmail
    FN: Eric  SN: Scace  MI: L.
  amateur radio BBS:  K3NA @K3NA







 7.9  Call Sign Analysis Algorithm


Matching Algorithm (ALG-2):
1.   Use ALG-1 on the input string.
2.   If input string does not contain a "/", done
3.   If there was no match, go to step 7
4.   If the match after the / is exact, done
5.   If the end string is /A, /M, or /P, done
6.   If the end string is a single numeric, replace the first non-leading
numeric in the string before the /. If ALG-1 produces a match, done.
7.   If the string exactly matches one of the */ entries, use that entry
8.   Use the shorter of the strings before and after the / (after if equal)
    and apply ALG-1

ALG-1:
1.   Find the most stringent straight match on the input string
2.   Find the most stringent equate match. If none, go to 4
3.   Make the substitutions, and find the most stringent straight match
(Can be done recursively up to a maximum limit.)
4.   If only one match was found, done
5.   If both a straight and substitution match were found, use the more
stringent.







 8.  Registering/Updates

GeoClock is distributed as shareware. This means that if you use and enjoy
the program, you are expected to register it.  See "Ordering GeoClock" for
details.  Registering your copy makes continued improvement and support for
GeoClock possible.  Furthermore, the registered version includes the zoom,
distance measuring, and city time display functions, plus many additional
maps.  You also get access to additional map files from the GeoClock
Bulletin Board System.

 8.  Registering/Updates
 8.1  Updates
 8.2  Available Maps
 8.3  About the GeoClock Bulletin Board
 8.4  GeoClock 7.1 special pricing
 8.5  Ordering GeoClock 7.1



 8.1  Updates

     If you have registered an older version of GeoClock, you can register
a new version without cost.  Just un-LZH the files from the newest
shareware version of GeoClock and run the REGISTER.EXE program that was
included on your original distribution disks.  The latest version is always
available from the GeoClock computer bulletin board system (BBS).







 8.2  Available Maps


     GeoClock includes a large number of maps.  All these maps have border
data for the former USSR, former Czechoslovakia, and former Yugoslavia as
of the release date of this version.  While the specific maps included
change from time to time to reflect changing interests, the following maps
are currently included with registration:

Africa                   Australia & NZ           British Isles
Canada                   Caribbean                Europe
Far East                 Former USSR              Japan
Meso America             Mexico                   Middle East
N America                New York City (2)        North Pole
S America                SW Asia/India            South Pacific
South Pole               United States (2)        US Regional (13)
View-From-Space (6)      World (3)

These basic maps are also available in 800x600 resolution.

There are four supplemental map sets providing detailed coverage of every
country in the world, the US states, and the Canadian Provinces.

North America has approximately 50 maps, including the 50 US states and the
Canadian provinces.

Europe has approximately 40 maps, including all the countries of the former
USSR.

Middle East / Asia / Pacific has approximately 35 maps.

Africa / South America has approximately 35 maps including Central America
and the Caribbean.


The maps distributed are changed from time to time to reflect changing
interests.  The GeoClock Bulletin Board always has all the maps available
to registered users.







 8.3  About the GeoClock Bulletin Board

    A free computer Bulletin Board System (BBS) provides support for users
of GeoClock.  It always has the latest version of the program available for
downloading.  In addition, it provides a forum for all interested parties
to exchange programs and information concerning GeoClock and high quality
mapping for the IBM PC.
    Everyone is welcome to use this BBS, but registered GeoClock users have
access to certain special files and have higher access limits. HAM package
owners also have access to the latest version of the HAM data base. Please
have your registration number handy when you log on for the first time.
Except for these special files, the messages and files on the board are
available to everyone. Your comments and suggestions are welcome.
    You need a modem (1200, 2400, 9600 v.32, 14400 v.32bis) and terminal
emulation software (such as Procomm or Crosstalk) for your PC to access the
BBS.  The BBS uses N-8-1 communications.  The BBS number is 703-241-7980.
This is a Washington DC metro area number. GeoClock is also available from
many Shareware catalogs, computer bulletin boards, and CompuServe (CSID
70461,2340).







 8.4  GeoClock 7.1 special pricing

License for multiple users at a single site (for LAN use, estimate the
number of LAN users of GeoClock):

Number    Price
1         $ 35/User
2-9       $ 30/User
10-20     $ 25/User
21-40     $ 20/User
41+       $ 15/User

Site licenses, corporate licenses, educational licenses, and other large
quantity licenses are available.  Contact GeoClock directly (voice 703-241-
2661, FAX [phone]) for details.

SVGA basic map set - $10.

Supplemental Map Sets: $ 20 for one, $30 for two, $35 for three, $40 for
all four ordered at the same time.  Available sets:
  Basic (included with GeoClock registration)
  North America
  Europe
  Asia/Pacific
  South America/Africa/Middle East

Spinning Globe: $15

HAM radio support package: $ 30

Custom maps - $30 for rectangular projection maps covering at least 120,000
square miles (at least 300 miles North to South) outside the US, or at
least 800 square miles (25 miles North to South) within the US.  Other
projections and sizes by negotiation.

Custom modifications to GeoClock - by negotiation.  Custom modifications
can generally be made on a fixed price basis after agreement to
specifications.

The supplemental maps and HAM package can be used by each registered user
without additional charge.  The supplemental map sets contain detailed maps
of all individual countries in the areas listed above.  Geo*.dat files
accompany each country(s) map(s) and provide both city and country data.

In all cases, the purchaser must make all required copies from the supplied
master copy, and must protect the software the same way the purchaser
protects its own proprietary software to ensure that the license is not
violated.

Terms: Payment must be by VISA, MasterCard, American Express, or check in
advance.  Purchase Orders are accepted only for unlimited site licenses and
custom programming.  No CODs.







 8.5  Ordering GeoClock 7.1

    Registration of GeoClock includes a copy of the latest DOS and Windows
versions of the program, a large set of maps (the basic set described in
"Available Maps"), a file with the names and locations of many world cities
for customizing the maps, a "starter set" of map overlay files, and an
installation program for automatic set-up on a hard disk. Updates to the
program are available to registered users at no charge from the GeoClock
BBS.
    The supplemental map sets(North America; Europe; Middle East, Asia &
Pacific; South America & Africa), and the HAM package, can be ordered with
the initial registration or later. Custom maps and quantity license
agreements are available. Write for details.
    Orders paid by cash or check are accepted by mail.  VISA, MasterCard,
and American Express orders may be made by mail, voice, FAX, or
electronically via the GeoClock BBS.
    Purchase orders, and checks drawn on or payable to banks outside the
USA, are not accepted. International postal money orders mailed separately
have not proved reliable and should be avoided.  In all cases, specify
whether 5.25" (1.2MB) or 3.5" (1.44MB) disks are required.

$35  GeoClock registration, DOS and Windows programs, and basic map set
$5   Extra for international air mail and handling
$10  SVGA basic map set
$20  One supplemental map set
$30  Two supplemental map sets
$35  Three supplemental map sets
$40  All four supplemental map sets
$30  HAM package (include your call sign and QTH)
$15  Spinning Globe program

You can also order the basic GeoClock registered versions ($35) via
CompuServe's SWREG  (search for the keyword GEOCLOCK)

GeoClock   2218 N Tuckahoe St, Arlington, VA  22205-1964
Voice: 703-241-2661 (normal business hours)
BBS: 703-241-7980 (24 hours)
FAX: [phone] (24 hours)
CompuServe: 70461,2340
Internet: [e-mail]