Slow Matrix Transmitter

Version V1.9



Slow Matrix Transmitter is an amateur radio soundcard digimode software for experimental transmission of low power/low speed signals over an SSB transmitter. It transmits audio encoded characters in a 5x7 pixel matrix font that can be made visible at the receiving side by an FFT spectrum analyzing software like Argo, Spectran, SpectrumLab or any QRSS signal grabber available on the Internet (see example below). The user interface is simple and self explanatory. The program can be run on Windows XP or higher. It is freeware for amateur use. To download Slow Matrix Transmitter right-click the link at the bottom of this page and then click "save target as". This software is under development. Return to this page from time to time to get the latest version. 





First beta release with mode "Concurrent Multitone Hell" (C/MT)


Fade in and fade out respectively at the beginning and end of column transmission for smooth and narrow b/w transitions


Display of average and peak power, tuning function


Display of average power over whole message, information in fields "Text to send", "Loop" and "Pause" saved in .ini file


Checkbox "Loop" and edit control "Pause" accessible even in transmit mode


Mode "Sequential Multitone Hell" (S/MT) also supported


Cosmetics in main dialog, documentation added, first production release


Length of text to send (in characters) in dialog; solved issue with Umlauts and other characters (were transmitted as blanks before); support for pilot tone


Introduction of a logfile (see menues File & View)


Checkbox "Reverse"


Support for transmitter PTT control (CAT)


Correct display of the time remaining to send the text even after a transmission is stopped; in loop mode a transmission interval (consisting of text transmission and pause) can be specified rather than a pause only


Edit control "Sent text" always scrolls to the left (so the last characters of the text sent are always visible); "Duration per pixel column" specified in milliseconds rather than in seconds (valid values from 300 to 60'000)


Error correction with high values for field Duration

V1.6b Loop interval valid up to 84600 seconds (one day)
V1.7 Introducing "Maximum average power" (C/MT only)
V1.7a Ability to run under Windows XP restored (got lost when the project was ported from Visual Studio 2008 to Visual Studio 2013 [V1.7])
V1.7b Modifications of the PTT interface
V1.8 Error correction with values of "Duration per pixel column" not matching a 1000 boundary (Mode C/MT)
V1.9 Error correction with values of "Duration per pixel column" not matching a 1000 boundary (Mode S/MT)

Slow Matrix Transmitter V1.9