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-
- Notes on HamComm: Dec.4th 1990
-
-
- - HamComm is a program for ham radio communications. In its current
- experimental state it supports reception and transmission of amateur
- radio teletype signals. The interesting thing about it is, that it
- doesn't require a modem. The audio output of the transceiver is
- connected to the serial port of any PC/XT/AT compatible computer thru a
- very simple and low-cost circuit. You need only one ic (op-amp LM741)
- and a few diodes, capacitors and resistors. For transmission the
- speaker output is connected to the microphone input of the transceiver
- thru a passive r/c filter. Audio frequency decoding and serial/parallel
- conversion is all done by the program.
-
- - HamComm will automatically detect the type of video adapter in use.
- MDA, CGA, EGA, VGA and Hercules are supported. All graphics routines
- are written in assembler for speed. The graphics display functions
- are not available on MDAs since the MDA has no graphics mode.
- No attempt has been made to avoid screen flicker (snow) on cheap CGAs.
-
- - HamComm will run on XT maschines but the graphics displays of the input
- signal are more fun to watch on an AT-class maschine. Nearly all of the
- functions can also be controlled by using a mouse. A harddisk is not
- required. All texts are written in english and the online help function
- includes the schematics for the interface circuit. There are also
- predefined standard phrases and a qth distance/direction calculator.
-
- - The converter schematics are included in the online help texts.
- 1. Start the program.
- 2. Hit F1 to start the help subsystem.
- 3. Hit the letter 'O' to select topic 'Overview'.
- 4. Hit the TAB key to select topic 'Converter' and hit return.
- 5. Scroll the help text using the cursor-up/cursor-down keys
- and read the text.
-
- - While the 'TUNE' display is active the center frequency can be abjusted
- using the 'Cursor-Left' and 'Cursor-Right' keys. The 'Home' key will
- reset the center frequency to the standard value of 700Hz.
- These adjustments can also be made using the mouse.
-
- - While the 'RTTY' display is active the 'AutoLetter' feature can be
- switched on and off using the control-L key. The default state is 'ON'.
- In 'AutoLetter' mode HamComm will automatically switch from figures to
- letters after five characters. 'AutoLetter' will also advance to the
- beginning of the next line on reception of a 'carriage return' character
- to avoid overwriting of previously received text.
-
- - While the 'RTTY' display is active normal text can be typed in the
- TX window. If the cursor reaches the end of the line the last word will
- wrap around to the next line.
-
- ! !
- ! A line of text is moved to the transmit buffer when: !
- ! !
- ! 1. a character is typed in the last position of a line or !
- ! !
- ! 2. the 'Enter' key is hit. !
- ! !
-
- Several keys have special meanings:
-
- - cursor-left, cursor-right, cursor-up, cursor-down:
- move TX window cursor.
-
- - control-A: go to beginnig of line
-
- - control-E: go to end of line
-
- - Home: go to first line
-
- - End: go to last line
-
- - Enter: send the current line to the TX buffer.
-
- - Insert: toggle insert mode
-
- - control-PgUp, control-PgDown:
- resize RX/TX window
-
- - control-Home, control-End:
- roll back RX window
-
-
- - The SPECTRUM function is a graphical display of the audio frequency as
- detected by HamComm. Please keep in mind that this is not the real
- audio spectrum. This program is not a substitute for a 10000$ spectrum
- analyzer. Some newer XTs may be fast enough to maintain a rapidly
- changing display but it's much more fun to watch this on an AT-Class
- maschine with color monitor.
-
- The display scale can be changed using the keys Page-Up, Page-Down,
- Cursor-Left, Cursor-Right and HOME. Hit the spacebar to reset all
- frequency counters to zero.
-
- - Option '-l43' on the commandline will switch to 43 line ega mode.
-
- - Option '-l50' on the commandline will switch to 50 line vga mode.
-
- - The author can be reached via the packet radio mailbox system.
- Send your error reports and other comments to DL5YEC @ DB0BQ.
-
- - Special thanks go to OM Winfried, DL1YCE, for contribution of the
- QTH locator routines and many helpful suggestions.
-
-
- 73 es 55 de django dl5yec
-