Real time applications for Ham Radio by VA3AGM



PC sound card based Real-time DSP filter and Spectrum scope

In my spare time I am working to improve this program. If you have any suggestion or want a particular functionality implemented please let me know.VA3AGM.

  • The program takes the input from a audio source. In Rx mode it can be the Line-In of the sound card. The input signal can be filtered using a Low Pass, High Pass or Stop band programmable DSP filter. The processed input is fed to the PC's speaker. The unprocessed or processed signal can be displayed in the Spectrum Display window.  
  • For Tx mode the input is the PC Microphone (you need to interface the PC with the transceiver).




Some useful hints: 
M1-M5 memory buttons
- used to apply a saved filter configuration
- right click to save the current working configurations (not saved to registry at this time)

 P1-P3 buttons
- used to play a registered message (like CQ CONTEST CQ ...)
- right click to start recording to a predefined file (for max 30 sec) into the TEMP directory (should be in Tx mode).

Max button
- click to set the Stop band filter central frequency on strongest signal
- by clicking on the Spectrum window will also set the filter to corresponding frequency (right click to delete the dotted vertical line)
- check the "stop" checkbox to activate the stop band filter

Tx button
- when activated will switch the audio input from LINE-IN to Microphone and will activate the DTR and RTS signals for the selected COM port

Spectrum scope window
- vertical bars are spaced at 500hz. The red ones to mark 1khz, 2khz and 3khz
- horizontal bars when logarithmic view is selected (log checkbox) are spaced at 20db starting with 0db at the bottom.
Updated August , 2014

PC sound card based Signal Generator


Can generate USB, LSB and DSB signal. Must use AF3 generator for the carrier frequency.

Updated Nov 12, 2003

CW software
Generates Morse messages from text and saves them as wav files (can be easy converted to MP3 format). Random text generation.

To generate random text: click on "Clear" button to delete the text from the transmission window. Type the desired characters (ie. QFHL) in "Random TX" edit box and check the "A" check box. Click on Transmit button.

Updatet Nov 27, 2003

The programs require Microsoft Windows  NT / 2000. They have not been tested on  Microsoft Windows 95, 98 or XP. No installation required.

The programs can be used free of charge. For comments and bugs report please contact VA3AGM.


Edited March 6, 2004 by Mircea VA3AGM / VA3PY.