Software Update for the WSPR Audio Signal Source

The PIC software for the Audio WSPR Source was updated to include on-chip WSPR message generation. On-the-fly grid square location updating for portable operation is also included if GPS timing is used.

The system now has the following capabilities:

- Internal timing or NMEA GPS timing for UTC synchronization of WSPR transmissions.
- On chip generation of the WSPR message.
- ‘On-the-fly’ GPS generation of grid square location for portable operation.
- Line or microphone output.
- Symbol data output available to modulate a VXCO
- Low power consumption allowing battery operation

The on chip generation of the WSPR message algorithm would not have been possible without the help of Andy Talbot, G4JNT. His excellent paper ‘The WSPR Coding Process’ provided a simple description of the encoding protocol.

The documentation is located at:

Gene W3PM