QRZ! Ham Radio 4/QRZ Ham Radio Callsign Database - Volume 4.iso/files/arrl/qst/qstdig12.93

Text File | 1994-11-20 | 43KB | 900 lines

DIGEST OF ARTICLES -- QST December, 1993

Following are digests of articles printed in the December, 1993 issue of
QST.  Such digests are being prepared for each issue of QST, and posted
periodically.  Subsequent issues will be posted one per week until they
"catch up" to the current date in mid-1994, thereafter monthly.

It is hoped that other hams will volunteer to post similar digests of
the other ham technical publications such as QEX, CQ, 73, COMMUNICATIONS
QUARTERLY, RTTY JOURNAL, et al.  Especially desirable would be digests
of publications in other countries, such as the RSGB RADIO COMMUNICA-
TIONS and ham magazines in Europe, Japan, Australia, and other countries
around the world.  We English speakers would especially enjoy them if
they were translated into our language, but they would also be valuable
additions to the world's knowledge if they were posted in the language
of origin.  Who knows?  Some bi-lingual ham somewhere might translate
them into English and re-post them.

Worldwide communications are getting better and better.  The time has
come to make the world's ham press available to all hams throughout the
world!

The major value of digests is to give readers sufficient information to
decide whether to obtain a copy of the full text.  If any U.S. reader
wants a copy of an article in QST, please inquire of other hams in your
own neighborhood.  Many have collections of back issues.  Anyone who is
unsuccessful in finding a fellow ham with a collection should try every
library in the area, especially those at universities and technical
colleges.  If all else fails, a copy can be obtained from the ARRL
Technical Department, 225 Main St., Newington, CT 06111-1494 USA for a
fee of $3.00 per copy.  Remember, it is both cheaper and quicker to
obtain one locally.

Readers in most other countries can obtain copies from their own
national ham organizations, sometimes translated into their own
languages.

-------------------------------CUT HERE---------------------------------
COPYRIGHT NOTICE: Copyright to all the following material from QST
Magazine is held by the American Radio Relay League (ARRL), effective on
the date of issue.  Permission is granted for redistribution of the
following in its entirety, or in part, provided that this copyright
notice is not removed or altered and that proper attribution is made to
ARRL as publisher of QST, to the authors of the original articles, and
to W. E. "Van" Van Horne, W8UOF, author of this compilation.
                              _________

                          TABLE OF CONTENTS


       (line number in parentheses - counting from CUT HERE line)

TECHNICAL ARTICLES (TA)

TA1:Taking the Mystery Out of Diode Double-Balanced Mixers          (67)
TA2:Measuring and Compensating Oscillator Frequency Drift          (117)
TA3:Computer-Controlled Electronic Test Equipment - Part 1         (160)
TA4:An Automated Mobile Radio-Direction-Finding System             (212)

PRODUCT REVIEW (PR)

PR1:The Ten-Tec Scout Model 555 MF/HF Transceiver                  (296)
PR2:QST Compares Packet TNCs                                       (382)

HINTS AND KINKS (HK)

HK1:Is Your Radio Equipment REALLY Grounded?                       (431)
HK2:Audio Patch Cords and RF                                       (451)
HK3:Tool Pouch Holds Hand-Held Transceivers                        (462)
HK4:How About NOT Using a 555?                                     (475)
HK5:A Fix for Faded Blue-Green Drake Dial Lighting                 (483)


TECHNICAL CORRESPONDENCE (TC)

TC1:FAX480 Updates                                                 (500)
TC2:Automobile RFI Solved                                          (518)

LAB NOTES (LN)

LN:Satellite-Tracking Software                                     (552)

NEW HAM COMPANION (NHC)

NHC1:The Frequency and Deviation Conspiracy                        (589)
NHC2:HF Mobiling - Taking it to the Streets                        (611)
NHC3:The Lure of the Ladder Line                                   (626)
NHC4:Radio and Railfanning                                         (645)
NHC5:The Doctor is IN                                              (668)
NHC6:The Joys of FM Simplex                                        (690)

GENERAL INTEREST ARTICLES (GI)

GI1:Heroics in the Heartland                                       (716)
GI2:Eritrea: A Nation Reborn                                       (737)
GI3:A Cold Season                                                  (768)
GI4:The First VHF Contest from Cuba                                (783)
GI5:Gatti-Hallicrafters: The First Grand Ham DXpedition            (803)
GI6:Ham and Former Ham Share 1993 Nobel Prize                      (838)
------------------------------------------------------------------------

TECHNICAL ARTICLES (TA)

Title>TA1Taking the Mystery Out of Diode Double-Balanced Mixers
Author>Joshi, Shankar
Source>QST Dec 93, pp. 32-35
Abstract>Description of double-balanced and double-double-balanced diode
mixers, their advantages, and how they are used.  Also a review of
representative available integrated-circuit mixers usable at frequencies
up to 35 GHz.

Digest>Mixers are commonly used in radio equipment to convert signals
from one band of frequencies to another through heterodyning.  A simple
mixer in a superheterodyne receiver accepts an input signal and a
local-oscillator signal; its output is an intermediate-frequency (i.f.)
signal.  But this output also includes the original two input signals,
plus various harmonics and beat frequencies.

The local-oscillator signal is the highest amplitude of any signal
present.  For this reason, the balanced-mixer was developed to balance
it out.  The double-balanced mixer takes it one step further and also
balances out the original signal input.  Consequently, to a first-order
approximation, the output of a double-balanced mixer is the i.f. signal
only.  Actually, all the other, unwanted, signals are still present but
reduced by orders of magnitude.

In this article, Mr. Joshi explains the design and application of the
most advanced types of double-balanced mixers available today.  The
heart of the DBM is a diode ring, or bridge circuit, comprised of four
Schottky diodes formed in a single integrated circuit.  The input and
local-oscillator signals are both applied in balanced form, each taken
from the secondary of a center-tapped ferrite toroidal transformer.  The
output of the circuit is typically taken between the center taps of the
two input transformers, in unbalanced form.

The author describes the characteristics of each of the major components
in considerable detail.  A table lists the parameters of ten
representative types of Schottky diodes which are rated for operation at
maximum frequencies that range from 4 GHz. to 35 GHz, depending upon
model number!

He further describes the double-double-balanced mixer (DDBM). Thus is a
circuit that takes the balancing process another step.  It uses two
Schottky quad-diode rings, each fed by a pair of toroidal transformers.
It tends to balance out the distortion products even more thoroughly
than the single DBM.  It also offers better signal-handling capabilities
and higher isolation between the inputs and the output.

DBMs are available as either discrete components or packaged complete
circuits including transformers, as well as ring diodes, in single cans.
                               _________


Title>TA2:Measuring and Compensating Oscillator Frequency Drift
Author>Hayward, Wes - W7ZOI
Source>QST Dec 93, pp. 37-41
Abstract>A description of a controlled temperature chamber and its use
in determining the frequency vs. temperature characteristic of
oscillators.  Also describes temperature compensation circuits and how
to adjust them using the chamber.

Digest>In this day when much amateur radio gear uses synthesized
frequency determination, there is still a place for analog oscillators
of the time-honored Hartley, Colpitts, and other classic designs.  All
of these show some amount of frequency drift, primarily due to
temperature changes.  The author describes the construction of a simple
controlled-temperature chamber that can be used to measure the
temperature-versus-frequency characteristic of oscillators.  By using
it, one can design and insert temperature compensation into the
oscillator circuit.

The author built his temperature chamber out of flake-board and
styrofoam.  For a heating element, he uses a light bulb.  A thermometer
continuously measures the inside temperature.  Also included is an
exhaust fan that can be used to exhaust hot air and draw in outside air
when rapid cooling is desired.  He suggests that another fan be placed
inside the chamber to stir the air and insure that the temperature is
uniform throughout.

 Mr. Hayward describes his experiences in measuring and developing
temperature-compensation circuitry for two oscillators.  His recommended
approach is that first, every attempt be made to make the
frequency-determining components, especially the coil and capacitor of
the oscillator tank circuit, to be as thermally stable as possible.
Then, when the exact relationship between temperature and frequency is
experimentally established, a capacitor with a negative
temperature-coefficient can be used to offset the measured drift and
reduce it nearly to zero.  He shows how the required size of such a
capacitor is calculated.

In his final summary, the author concludes: "You can have 'rock stable'
oscillators if you're willing to build and apply some simple measurement
gear".
                               _________


Title>TA3:Computer-Controlled Electronic Test Equipment - Part 1
Author>Portugal, Ron
Source>QST Dec 93, pp. 42-50
Abstract>First installment of construction articles for computer-based
bench instruments.  This one covers the microprocessor board that will
be used as the base for the instruments to come.

Digest>Most hams today seem to have computers in their shacks, or are
contemplating them.  They are frequently used for keeping logs, filling
out QSL cards, and for operating in the ham digital modes: RTTY, Packet,
PACTOR, etc.  This article adds one more use for the station computer.
It can be used as a control center for test equipment.  As such, it will
operate as the power supply, provide the control logic, record the data,
display the results either as numbers or graphs, and provide a base on
which relatively inexpensive, very effective bench equipment can be
home-built.

In this first installment, Mr. Portugal describes, and provides
construction details for, building the microprocessor board that will
become the first building block of the array of test instruments.  It
utilizes a Zilog Z-8671 microcomputer chip.  That chip contains an
RS-232 serial port in addition to its general purpose central processing
unit (CPU).  All communications between it and the main computer are
through the RS-232 port.

The Zilog chip is designed for use as a controller and is popular
because of its ease of use.  All programming is done in the Basic
language.  Many of its functions are preprogrammed when the chip is
manufactured.

The author plans, in future installments, to give full construction
details for building the following items:

        1. Completely monitored, triple-section power
           supply.
        2. Inductance/capacitance (L/C) meter.
        3. 1-Hz. to 10-MHz. frequency-synthesized
           sine/square-wave generator.
        4. 500-MHz. frequency counter.
        5. Provision for additional instruments to be added
           in the future.

He indicates that all of these pieces of equipment can be built for
costs ranging from $50.00 to $150.00 each.

A complete kit of parts for the microcomputer board, also including the
Zilog Technical Manual, is available from Ronald J. Portugal, 52 Susan
Lane, North Haven, CT 06473 for $150.00 plus $4.00 for domestic
shipping.
                               _________


Title>TA4:An Automated Mobile Radio-Direction-Finding System
Author>Flanagan, Robert H. - KA1RBH and Calabrese,
        Louis A., Jr. - N1LZD
Source>QST Dec 93, pp. 51-55
Abstract>Describes an automated RDF system built into an automobile.  It
calculates bearings automatically.  The only human action required to
find a hidden transmitter is to plot the bearings on an accurate map.

Digest>The authors describe a very sophisticated radio-direction-finding
(RDF) system built into an automobile. They state that such a system
"currently costs well into four figures...." so is not for widespread
amateur use, but it is described for general background information.

The system is assembled from a number of components, each of which
represents a recent development in technology. The bearing of a radio
signal in relation to the body of the vehicle is measured by a Doppler
RDF unit that uses four vertical quarter-wave antennas mounted on the
roof.

To convert the relative bearing to a true compass bearing requires that
the heading of the vehicle be measured accurately.  This is done using a
flux-gate compass.  Then the absolute location of the vehicle must be
known and located on a detailed map.  The precise location is measured
by a global-positioning system (GPS) receiver. This is the
satellite-based measuring system that was developed by the U.S. Defense
Department and has only recently been released for civilian use.

Finally, bearings taken from the vehicle at two or more locations must
be plotted in relation to an accurate map to determine the location of
the transmitter being sought. This is done on a laptop computer that
automatically locates the intersection of two or more bearings in
relation to the United States Geodetic Survey (USGS) Universal
Transverse Mercator (UTM) grid.  That grid covers the entire U.S. with
squares, 1 km. on a side, which are plotted on very detailed
topographical maps.

Once the computer shows the exact location of the transmitter in
relation to the grid, it is easy to find it on the appropriate USGS map.
The computer program that accepts the data from the RDF unit, the
compass, and the GPS receiver, processes them, and displays the bearings
on a grid, was written by the authors.  Copies are available from Mr.
Flanagan, KA1RBH.

One practical problem that the authors had to overcome in the operation
of the system was the fact that signals are received not only directly
from the transmitter but also by reflection from buildings, cars, metal
poles, and a myriad of other objects common in residential areas.  The
system must sort out the direct signals and ignore the reflected ones.

In order to eliminate most of the stray signals, the program accumulates
bearings for one minute at a time, selects the angle from which the
largest number of bearings was detected, and rejects any that were more
than 15-degrees from that angle.  Then it averages all the bearings
within that angle to report the most probable direct bearing. As the car
moves, more and more bearings are calculated and, as the vehicle gets
closer, the uncertainty of position becomes smaller and smaller.

The authors describe two improvements that they would like to add to the
system.  First, it would be a great convenience to be able to display a
highly detailed map on the computer screen with the grid squares and
plotted bearings superimposed so that they could dispense with the
cumbersome paper maps.

Second, they are considering using packet radio to interconnect all the
"hunters" in a foxhunt so that all participants would have the benefit
of the bearings taken by the others.  The result would be: "Working as a
group, we could watch our bearings zeroing in as our screen display is
updated automatically.  Even the fox could get in on the action and
watch our progress!"  They did not address the question of whether this
would defeat the purpose of the foxhunt!

The authors report that they have utilized their automated system in
several foxhunts and have found it to be a "great tool" because it is
"fast, accurate, and allows the operator to concentrate on other
activities, such as driving and picking the next location for a
bearing."
------------------------------------------------------------------------

PRODUCT REVIEW (PR)
     conductor: Mark Wilson, AA2Z
                Editor, QST
                        _________


Title>PR1:The Ten-Tec Scout Model 555 MF/HF Transceiver
Author>Newkirk, David - WJ1Z
Source>QST Dec 93, pp. 77-80
Abstract>A review of the least expensive, nearly full-function HF
transceiver now on the market.

Digest>The Ten-Tec Scout is a highly innovative new transceiver that
offers good performance on all bands from 1.8 to 29.0 MHz.  It features
50-watts output, very small size, a built-in keyer, and an ultra-low
price!

One of the ways that Ten-Tec has kept the price down involves the method
of band changing.  There are no bandswitch and built-in multi-band
components!.  Instead, a separate module for each band must be plugged
into a front- panel receptacle.  The listed price of $495.00 is actually
for a single-band receiver; each additional band requires the purchase
of a module for $25.00.

Reminiscent of the famous National HRO receivers of 40 or more years
ago, the plug-in modules can be considered either an advantage or a
drawback, depending upon one's point of view.  For one thing, buyers do
not have to pay for bands they do not intend to use.  Also, one can make
an argument that plug-in coils can be more efficient than the
bandswitched variety.  On the other hand, if one buys a full complement
of 8 extra plug-in modules, the additional $200.00 makes a total price
not far below that of competitive rigs.

In the process of keeping both the physical size and also the price
small, Ten-Tec has made some compromises.  For one thing, the
frequency-determining circuit is a permeability-tuned oscillator, not a
synthesizer.  Like all oscillators, this one is subject to some drift as
well as step changes caused by physical jarring.  But the drift is not a
big problem, for two reasons:  First, the rig contains a frequency
counter that displays the actual frequency; and second, the
frequency-counting software detects the drift and counters it
automatically!  These compensating actions are not instantaneous,
however, and both the operators and others in QSO with them can detect
the frequency changes as they occur.

The Scout's small front panel contains only 5 knobs: tuning, audio gain,
i.f. bandwidth, offset tuning (RIT), and microphone gain.  In addition,
there are three switches, two jacks, a four-digit frequency display, 1
LED indicator, and a meter.

The switches are: (1) a 3-position Tune-Off-Noise Blanker.  In the Tune
position, the transmitter emits a low-power signal (CW) for antenna
adjustment.  The Noise Blanker activates the impulse-noise limiter
circuit. (2) Speed-Off-RIT.  In the Speed position, it allows one to
adjust the speed of the internal keyer upward or downward by pressing
the dot or dash paddles; the RIT position turns on the receiver offset
tuning. (3) Power (on-off).

The two jacks are for a microphone and for audio output to speaker or
headphones.  The meter displays signal strength while receiving, and
either output or SWR while transmitting.  The single LED indicator,
"ALC", indicates when the automatic level control is operating during
transmission.

During single-sideband operation, the appropriate sideband is selected
automatically by the band module in use.  It is not possible to reverse
sidebands.

The reviewer operated the rig and paid special attention to the
receiver, since it is in the receive function that most inexpensive
transceivers show their limitations.  He was pleasantly surprised at the
Scout's performance.  It uses a single i.f. at 6144 KHz., so image
rejection is not as complete as with the latest top-of-the-line
transceivers, but the images are unlikely to cause any real problem
except under unusual operating conditions.

I.f. filtering is done by multiple-crystal filters.  On CW, the reviewer
found the selectivity to be "acceptably good - it suitably knocks down
the CW audio image even with i.f. bandwidth at its widest setting".

In transmitting, on CW the keying is excellent and the rig always
operates full break-in.  Its switching time is fast enough even for
AMTOR operation.  On SSB, its audio is good.

The AGC operation is a compromise between SSB and CW; it uses a fast
attack and slow decay.  The reviewer found its operation to be "first
rate".  His final conclusion was: "I like the Scout.... Its simple
controls and straightforward operation put a minimum of mechanism
between me and the stations I want to work."
                               _________


Title>PR2:QST Compares Packet TNCs
Author>Ford, Steve - WB8IMY
Source>QST Dec 93, pp. 80-81
Abstract>A review of five current terminal-node controllers for packet
only.  Included are units built by Kantronics, DRSI, MFJ, AEA, and
PacComm, all priced between $100 and $150.

Digest>Two-meter packet is the most popular digital mode in ham radio
today.  There are several reasons for this.  For one, the advent of
"no-code" licenses means that the majority of new hams head for VHF.
Anyone with a computer and a 2-meter rig, even a hand-held, can get onto
Packet easily and at relatively low cost.  More importantly, packet is
an exciting mode.  Lots of new things are happening, networks are
rapidly expanding, high-speed trunk lines are criss-crossing the
countryside, and digital technology naturally appeals to a great many
hams.

For a ham who already has a computer and a 2-meter station, the only
added equipment he needs to get onto packet is a terminal-node
controller (TNC).  Of course, one can use an expensive multi-mode
communications processor (MCP) that provides a wide variety of operating
modes in addition to packet, at a correspondingly high price.  But if
one is interested only in VHF packet, a late-model packet TNC can be
bought for a list price ranging from about $115.00 to $150.00.  This
article reviews five such models now on the market.

The 5 units reviewed are the Kantronics KPC-3, the DRSI Model DPK-2, the
MFJ Model 1270B, the AEA Model PK-88, and the PacComm Tiny-2 Mark II.
All five of these provide the most basic features: Mailbox, KISS mode,
and Host mode operations.  All but the DRSI DPK-2 also provide automatic
mail handling, so that one can make arrangements with their local packet
bulletin-board system (PBBS) and leave the receiver on continuously.
Then, any mail that is received by the PBBS will be automatically
forwarded to one's own computer.

The selection between the 5 models will probably hinge on what other
features besides those listed above are of interest to the buyer.  Other
items to be considered are: whether one is also interested in packet on
the HF bands; receiving weather maps by facsimile; 100-percent
compatibility with the original Tucson Amateur Packet Radio (TAPR) Model
TNC-2; whether software is included; and other factors.
------------------------------------------------------------------------

HINTS & KINKS (HK)
     conductor: David Newkirk, WJ1Z
                Sr. Asst. Technical Editor
                               _________


Title>HK1:Is Your Radio Equipment REALLY Grounded?
Author>Cardwell, Martin L. - NB3T
Source>QST Dec 93, p. 85
Abstract>How to assure a low-resistance ground connection.

Digest>The writer had his common ground point in the shack grounded to a
rod driven into the earth.  His beam antenna was likewise connected to a
ground rod at the base of the tower.  In an attempt to trouble-shoot
QRN, he found that there was very high resistance between the two ground
rods, indicating that either, or both, had very high contact resistance
with "true ground".

To cure the problem, he replaced his old ground rods with pure copper
tubing.  Now he measures between 10- and 15-ohms between the two rods
that are some 45-feet apart.  He intends to monitor this resistance
periodically to ensure that the ground connections will continue to have
low resistance in the future.
                              _________


Title>HK2:Audio Patch Cords and RF
Author>Swynar, Edward "Eddy" Peter, VE3CUI
Source>QST Dec 93, p. 85
Abstract>Use r.f. coax, not audio patch cords, for rf!

Digest>Mr. Swynar cautions all hams not to use audio patch cords for
r.f. since the audio shield is not a good r.f. shield.  Use coaxial
cable designed for radio use.
                               _________


Title>HK3:Tool Pouch Holds Hand-Held Transceiver
Author>Hendrey, Bill - KC6JGS
Source>QST Dec 93, p. 85
Abstract>A holster available at hardware stores just fits the ICOM
IC-24AT hand-held transceiver.

Digest>Mr. Hendrey points out that a Skil holster, which is designed to
hang from one's belt and carry a Skil tool, exactly fits the ICOM
IC-24AT hand-held transceiver.  The stock number designation of the
pouch is "Twist Pouch No. 92160", available at hardware stores.
                               _________


Title>HK4:How About NOT Using a 555?
Author>Newkirk, David - WJ1Z
Source>QST Dec 93, pp. 85-86
Abstract>Suggests using an LM322 or LM3905, instead of a 555, timer chip
in the 10-minute timer circuit described by Conklin in HK, QST Nov 93.
                               _________


Title>HK4:A Fix for Faded Blue-Green Drake Dial Lighting
Author>Ross, Arnold J. - W2NXC
Source>QST Dec 93, p. 86
Abstract>When the color fades from light bulbs, paint them with nail
polish.

Digest>The writer notes that the dial lights on Drake ham equipment
which are blue-green when new, fade in time.  He recommends restoring
the original tint by painting the bulbs with blue nail polish, Artmatic
USA No. 163 Peacock Blue Nail Enamel, bought at K-Mart.
-----------------------------------------------------------------------

TECHNICAL CORRESPONDENCE (TC)
     conductor: Paul Pagel, N1FB
                               _________


Title:TC1:FAX480 Updates
Author>Taggart, Ralph - WB8DQT
Source>QST Dec 93, pp. 87-88
Abstract>Describes improved software for slow-scan TV and FAX.

Digest>This letter is of interest to hams who are involved in slow-scan
TV (SSTV) and FAX video modes.  The writer is the author of the FAX480
software that provides an operating program for FAX and SSTV
transmission and reception.

In his letter, Mr. Taggart discusses the details of his latest upgrade,
known as FAX484/FAX481P.  The new upgrade improves the loading of images
into memory, simplifies a manual restart, and provides a better method
of overcoming problems caused by noise or QRM interrupting the reception
of an image.
                               _________


Title>TC2:Automobile RFI Solved
Author>Zak, Stan - K2SJO
Source>QST Dec 93, p. 88
Abstract>Toyota driver corrects RFI problem after receiving no help from
the manufacturer.

Digest>The writer reports problems that developed when he installed a
Kenwood VHF transceiver in his 1993 Toyota Camray.  When he transmitted
at full 50-watts output, a dashboard warning light indicated that the
taillight had failed.  He followed of Toyota's recommendations to solve
the problem, without success.  He finally solved it by shielding the
rear-window brake-light assembly with a grounded-wire screen.  The
screen did not affect the brightness of the light.

Ed Hare, KA1CV, ARRL Laboratory Supervisor, appended a comment to the
letter.  He reports that he had contacted the Toyota Technical
Department about frequent problems reported by hams who had installed
transceivers in their automobiles.  He was assured that transmitters
running up to 100-watts should have no problems with Toyota vehicles.

The fact that Mr. Zak got no help from the manufacturer but was able to
find such a simple solution to his problem shows that Toyota has not
spent the engineering time required to solve such trivial problems.  It
seems that their assurances have little value.  Mr. Hare is accumulating
such reports and intends to keep pressing recalcitrant manufacturers to
obtain meaningful help.
------------------------------------------------------------------------

LAB NOTES (LN)
     conductor: Steve Ford, WB8IMY
                Asst. Technical Editor
                               _________


Title>LN1:Satellite-Tracking Software
Author>Ford, Steve - WB8IMY
Source>QST Dec 93, pp. 89-90
Abstract>Describes satellite-tracking software, what it does, and how to
use it.

Digest>This month, Mr. Ford has prepared, in Question and Answer format,
a description of satellite-tracking programs and what they do.  The
function of such software is to tell the user when a particular
satellite will appear above the horizon, and specify its exact postion
continuously as it passes overhead.  To do this, the computer must be
given the latitude, longitude, and elevation above sea level of the ham
station.

It also must be given the orbital elements of each satellite.  Orbital
elements are sets of numbers used to describe the orbit of a satellite.
They can be obtained from various bulletin boards, both via telephone
and packet radio.  They must be updated periodically since orbits change
slowly with time.

Various software packages offer different features.  In many cases, they
display maps that plot the satellite at all times.  Some programs also
provide control outputs that can be used with antenna mounts that are
motorized in both azimuth and elevation to position the antenna
automatically and follow the satellite as it passes overhead.  The
article lists the name and address of five different sources of
appropriate software.
------------------------------------------------------------------------

NEW HAM COMPANION (NHC)

        The New Ham Companion is a regular monthly section
in QST that concentrates on articles of primary interest to
newcomers to ham radio.
                               _________


Title>NHC1:The Frequency and Deviation Conspiracy
Author>Leahy, Bill - K0ZL
Source>QST Dec 93, p. 66
Abstract>Why it is necessary that FM frequency and deviation be
carefully adjusted, and how to do it.

Digest>The author explains what frequency and deviation mean in
frequency-modulated (FM) transmissions, how important it is that they
be adjusted properly, and how to go about such adjustment.  Especially
when working through a repeater, it is necessary to adjust the frequency
of the rig to within about 0.2-KHz. of nominal and also to adjust the
deviation to a total of 5-KHz.  If the repeater requires a continuous
tone-coded squelch system (CTCSS) tone, then the deviation must be
reduced to about 4.5 KHz. to allow for the addition of the tone.

If both frequency and deviation are not properly set, it is probable
that the signal will be "chopping" in and out of the repeater because,
on voice peaks, the carrier energy is outside the passband of the
repeater's receiver.
                               _________


Title>NHC2:HF Mobiling - Taking it to the Streets
Author>Gold, Jeff - AC4HF
Source>QST Dec 93, pp. 67-69
Abstract>Describes operating HF mobile from an automobile and suggests
some suitable equipment.

Digest>Mr. Gold describes his enthusiasm for operating mobile on the HF
bands from his automobile.  Then he describes a number of commercial
antennas and also small-size transceivers handy for mounting in or under
the dashboard.  He points out that almost any kind of HF operating can
be done from a vehicle, including nets, DXing, contesting, digital-mode
operating, rag chewing, and QRP operating.
                               _________


Title>NHC3:The Lure of the Ladder Line
Author>Ford, Steve - WB8IMY
Source>QST Dec 93, pp. 70-71
Abstract>The advantages of open-wire line for feeding a dipole.

Digest>Mr. Ford describes the advantages of feeding a multi-band dipole
with balanced open-wire line, as opposed to coax.  He relates his own
experience when he converted from coax to 450-ohm ladder line and
achieved much better performance.  He largely refutes the common fears
of problems arising from using open-wire line near metal.

He relates advice that he received to the effect that crossing a metal
window-sill at right angles, for example, is no cause for worry so long
as there is not an actual metal-to-metal contact.  Also that ladder-line
can be run within a few inches of even large masses of metal, such as
aluminum siding, so long as a separation of a few inches is maintained.
                               _________


Title>NHC4:Radio and Railfanning
Author>Clark, Brad - NP4AI
Source>QST Dec 93, pp. 72-75
Abstract>Activities of railfans and how they use ham radio in them.

Digest>There are a large number of people who call themselves railfans
and are interested in all aspects of railroad operation.  Most are
especially interested in the historical aspects, including steam engines
and any tools and equipment dating from the era of steam.

Recent laws making mobile use of radio scanners illegal to most people
have led a number of railfans to earn ham radio licenses, because hams
are explicitly allowed to use mobile scanning equipment.  With a ham
license, they can not only monitor traffic regarding rail operations but
they can also use VHF/UHF HTs to keep in contact with other fans on an
outing.

The author describes organized activities carried on by railfans,
includes hints of how to enjoy them, and cautions against unsafe,
discourteous, or illegal activities.
                               _________


Title>NHC5:The Doctor is IN
Author>Various
Source>QST Dec 93, p. 76
Abstract>Questions and answers for ham newcomers.

Digest>This is a regular monthly feature in the New Ham Companion
section.  It is a series of questions and answers of special interest to
newcomers.

In this month's column, questions discussed were ways to route the coax
feedline to a 2-meter, 4-element quad antenna; DX packet clusters;
radial wires used with a vertical antenna; and different types of
memories used with personal computers.
------------------------------------------------------------------------

RADIO TIPS (RT)

These are short items, scattered among the articles in the NEW HAM
COMPANION section.
                               _________


Title>RT1:The Joys of FM Simplex
Author>Ford, Steve - WB8IMY
Source>QST Dec 93, p. 75
Abstract>Long QSOs should be direct between amateurs (Simplex), not
through repeaters.  They should take care to avoid frequencies where
they might interfere with other activities.

Digest>In this tip, the writer reminds readers that repeaters can only
carry one QSO at a time, so common courtesy requires that QSOs carried
by repeaters should be kept as short as possible so that others can get
their chance.

If two people want to carry on a long QSO on a VHF band, they should try
to do it by operating simplex, that is talking to each other directly.
They should move to a frequency set aside for simplex operation where
they are not likely to be bothered, or bother others.

Included in the article is a table of popular FM simplex frequencies on
the 6-meter, 2-meter, 1.25-meter, and 70-cm. bands.  To find other
simplex frequencies, refer to the ARRL Repeater Directory which
describes all VHF/UHF band plans in detail.
------------------------------------------------------------------------

GENERAL INTEREST ARTICLES (GI)


Title>GI1:Heroics in the Heartland
Author>Palm, Rick - K1CE
Source>QST Dec 93, pp. 21-26
Abstract>Public service by radio amateurs during the Summer, 1993
floods.

Digest>The floods in the upper midwest during the summer of 1993 were
the most widespread, long lasting, and devastating floods in the modern
history of the United States.  But the loss of life was relatively
small.  Some part of the credit for this must go to the efficiency of
communications that were able to get help promptly in the many
life-threatening situations that developed.  Ham radio volunteers played
a large role in this.

Mr. Palm has assembled an article made up of reports by ARRL Emergency
Coordinators and other members of the ARRL Field Services relating the
work done by ham volunteers in various parts of Kansas, Missouri, Iowa,
Minnesota, Illinois, and others of the states hardest hit.
                               _________


Title>GI2:A Nation Reborn
Author>Enderud, Einar - LA1EE and Wiig, Erling - LA6VM
Source>QST Dec 93, pp. 27-31
Abstract>Ham radio activities in Eritrea.

Digest>Eritrea, a new nation located near the Horn of Africa and facing
the Red Sea, became independent April 27, 1993.  Only a little more than
a month later, four hams from Norway and one from Japan established the
first Eritrean ham station, E35X.  The authors were two of the hams who
participated and in this article relate their experiences.

What had originally started out to be a DXpedition grew to be much more.
The five visitors not only established the ham station and put it on the
air for many days of intensive operation under the pressure of
tremendous pileups, but also they conducted seminars on ham radio at two
different places to two different groups.  The first was a course of
instruction in amateur radio for personnel of the Eritrean
Telecommunications Authority (Telecom) and the other was for the
students and faculty of the Asmara Technical School.

Finally, when the seminars were completed, they helped organize a radio
club at the school, donated their equipment to it, and helped install
the antennas and start up the station equipment for the club members.

During their brief stay, they had made a total of 19,600 contacts and
provided a new country for nearly that many hams worldwide.  They
enjoyed themselves thoroughly and made many friends among the friendly
and warm-hearted Eritrean people.
                               _________


Title>GI3:A Cold Season
Author>Vaughan, Bruce - NR5Q
Source>QST Dec 93, pp. 56-57
Abstract>Fiction.  An aged ham keeps in contact with his children by
radio.

Digest>This is a fictional tale of a ham oldtimer, in his mid-70's, a
widower, living alone with his dog.  His children live far away and he
rarely has the opportunity to enjoy them and his grandchildren.  But he
keeps in contact with his son who is a ham.  At the end of the story, he
is pleased to learn from a message received from his son, via packet,
that his two grandsons have received novice licenses and will meet their
grandfather on 40-meter CW the following Saturday morning.
                               _________

Title>GI4:The First VHF Contest from Cuba
Author>Coro, Arne - CO2KK
Source>QST Dec 93, p. 58
Abstract>Cuban participation in the June, 1993 VHF QSO Party.

Digest>Mr. Coro and a number of other Cuban hams participated in the
June, 1993 VHF QSO Party.  They were pleased to find sporadic-E openings
on 6-meters to the USA on Saturday, and on the following day, similar
openings allowed contact with several Caribbean islands.

On 2-meters, tropospheric propagation allowed contacts with many U.S.
stations in Florida.  In the end, they had logged 260 stations on
6-meters in 80 grid squares. On 2-meters they made 62 contacts in 11
grid squares.  The author states that news of their success spread
through the rest of the Cuban ham community and many Cuban hams are now
building single-sideband transverters for 6- and 2-meters, and others
are making plans for UHF operations on 432- and 1096-MHz. bands.
                               _________


Title>GI5:Gatti-Hallicrafters: The First Grand Ham DXpedition
Author>O'Brien, Mike - N0NLQ
Source>QST Dec 93, pp. 59-63
Abstract>A DXpedition sponsored by the Hallicrafters Company in 1947 was
an enormous production.

Digest>In 1947, Attilio Gatti, an Italian explorer, convinced his
friend, Bill Halligan, founder and CEO of the Hallicrafters Company,
manufacturer of ham gear, to organize a ham DXpedition to go to the area
of East Africa called the "Mountains of the Moon", near Lake Victoria
and Mt. Kilimanjaro, in what was then Tanganyika Territory and Kenya,
under British control.

The expedition was organized in a grand manner.  Four special 23-foot
long trailers were designed and built, one of which was outfitted as an
elaborate and completely equipped ham station.  As finally organized and
equipped, the expedition moved in a caravan of at least eight vehicles -
trucks, station wagons, and tractor-trailers - manufactured by
International Harvester.

Shipped aboard a freighter, the entourage landed at a port in Kenya in
January, 1948.  Over the succeeding nine months, it travelled 5000 miles
by land logging QSOs all the way.  The total number of contacts made is
not known, because the logs were somehow lost.

The article does not include any estimate of the costs involved in the
expedition, but they must have been enormous.  If it is true that Mr.
Halligan and Hallicrafters absorbed the major part of the cost, it
appears that he considered it advertising expense.  He must have felt
that it was reasonably successful because a few years later
Hallicrafters again sponsored a DXpedition, but that time on a much
smaller scale, to Clipperton Island.
                               _________


Title>GI6:Ham and Former Ham Share 1993 Nobel Prize
Author>Karpf, Stephen - WJ2P
Source>QST Dec 93, p. 91
Abstract>The 1993 Nobel Prize for Physics was won by two American hams.

Digest>The 1993 Nobel Prize in Physics was awarded to two Americans, Dr.
Joseph Taylor, K1JT and Dr. Russell Hulse, ex-WB2LAV.  Both developed
their interest in radio as hams at young ages.  Dr. Taylor was
originally licensed at age 13 and Dr. Hulse, also, got his license when
he was a teen-ager.

Their ham activities led them to become interested in antennas, and from
there they graduated to radio astronomy.  Working together at the great
radio telescope at Arecibo, Puerto Rico, they discovered and studied a
binary pulsar.  It was this discovery, and their theoretical
explanations of what they observed, that earned them the prize.
------------------------------------------------------------------------


73, Van - W8UOF

[e-mail]