I've been tracking Greencube all week and while I can hear the bird well and decode packets but I'm having very little success with transmit. Out of at least 100 attempts I think I've had/seen 4 replies. I think I should be seeing my own packets being retransmitted by the bird but I do not.

I'm using an FT-847 with the audio interface connected to the TRS port for AFSK. I've used the same radio and interface for terrestrial FT8 on 2m and 432 with no problems.

The antenna is an 11 element m2 yagi which, along with an 8 element m2 2 meter yagi, is the same array on an az-el rotor that I use for other satellites.

I'm running the new version of SatPC32ISS, UZ7HO's SoundModem V.005b and GreenCube Digipeater V0.15. Doppler tracking seems stable and the received audio is centered around 1500hz on the waterfall.

I've tried a couple different sound cards and experimented with transmit audio level thinking that I might be overmodulated. I've also tried power levels from 10 to 100 watts and I've tried adjusting the TXDelay ins SoundModem from 400 ms to 1000 ms.

At this point I am at a loss and don't know what to try next. I'd be grateful for advice from the group.

de K0EKL EN37