[amsat-bb] PicSat demodulator?

Scott scott23192 at gmail.com
Wed Jan 17 16:56:00 UTC 2018

Despite the documentation, PicSat beacons so far have been 1k2 BPSK.

There is a 1k2 BPSK software modem in:


... and the demod on that would be USB.  Of course the bandwidth &
centering of the audio output is critical for this scheme; what works well
for me is to output the audio (I use HDSDR into VB Audio virtual cable) at
4 KHz with the signal centered on the 2000 Hz mark.  If you match that 2000
Hz center on the 1k2 BPSK software modem screen, it decodes very nicely.

-Scott,  K4KDR


On Wed, Jan 17, 2018 at 11:19 AM, Ken Swaggart <k.swaggart at charter.net>

> Have been trying to decode the 435.525 MHz beacons from PicSat without
> success. The modulation is described as "GMSK modulation with G3RUH
> scrambling". I'm assuming the baud rate is 9600.  Normally I use UZ7HO's
> High-Speed SoundModem for telemetry reception.
> Tnx,
> Ken, W7KKE

More information about the AMSAT-BB mailing list