so ive been trying to work FO-29 for about three weeks now and i cant seem to close a contact. i can hear the downlink fine on 435.795 USB, signals are decent when the bird is above maybe 15 degrees elevation, but when i transmit on 145.950 USB i just cant find my own signal on the downlink. i know the transponder is inverting so LSB up and USB down but ive read conflicting stuff about whether FO-29 is actually inverting or not at this point.

my setup is a ft-847 with a pair of yagis on a G-5500 and im running gpredict for tracking. doppler correction is manual right now which is probably part of the problem. the az/el rotator seems to be following the pass okay but im not super confident in my antenna calibration. anyway the main thing is i cant hear myself in the passband at all even at like 10 watts. either im way off frequency or the bird just isnt hearing me, not sure which.

anyone work FO-29 recently and know if the transponder is even active these days? i feel like im chasing a dead bird half the time

FO-29 has been pretty hit or miss honestly, the transponder goes in and out and theres been stretches of weeks where its just not on. worth checking amsat's status page before you spend a whole pass hunting for your own signal.

that said your doppler situation is probably killing you even if the bird is active. on a linear transponder the uplink and downlink are shifting in opposite directions relative to each other because of the inverting nature, so you really do need to be correcting both at the same time or youre chasing your tail. gpredict can do split doppler if you set it up right with two radio profiles, one for uplink one for downlink, but getting that working with the 847's CAT takes a little fiddling. i was in the same boat for a while and once i got the doppler sorted i found my signal pretty quick. start with low power too, like 5 watts, you dont need much if the link is closed and itll save you from accidentally stomping on someone else in the passband

yeah FO-29 transponder has been flaky for a while now. i actually gave up on it and moved over to SO-50 for FM just to get some satellite contacts in the log while i sort out my linear transponder technique. not the same thing i know but at least i know something is coming back at me when i transmit.

the inverting transponder thing tripped me up too when i started. the way i think about it is if you tune up on the uplink your signal moves down in the downlink passband, so when youre hunting for yourself you gotta tune the opposite direction than feels natural. took me an embarrassingly long time to internalize that