FalconSat Success!

Copying the 9600 baud telemetry signal from Falconsat 3 has been a objective ever since we set up the W2MMD satellite station. This satellite was built by cadets at the US Air Force Academy and was turned over for ham use after its military mission was complete last year.  Its primary communication method is 9600 baud GMSK telemetry, and it also has a store-and-forward BBS system onboard. Unfortunately it's in a low-latitude equatorial orbit so the elevation at our QTH never gets above about 40 degrees.  For months I've tried to copy it but couldn't get it to decode using the UZ7HO modem. Adding the 70 cm preamp at the antenna in June brought up the signal significantly but I still couldn't decode it on Field Day. Then tonight I made one adjustment and the signal came slamming into the modem, and out spewed a barrage of coded telemetry and other packets at 9600 baud. See the signal strength below along with the modem output that was piped into the AGW KISS decoder.



The secret? Set the receive mode to WFM instead of NFM! Once I made that change the modem IMMEDIATELY started to decode - and kept decoding until almost LOS. Some of the packets are readable but many are not. The BBS uses a program called WISP to communicate so I'll have to get that working now that I can listen to it. But the big obstacle has been conquered!

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