so ive been messing around with AO-7 and some of the other linear birds for a few months now and i think i finally understand the basics but the doppler thing is still tripping me up. like i get the concept, the satellite is moving so the freq shifts, but im confused about which VFO to adjust and when. i have an IC-9700 and im using Gpredict for tracking which works great for az/el but im not 100% sure if i should be letting it auto-correct both uplink and downlink or just one of them.

the passes ive had where i could hear myself in the passband were mostly okay but a few times i drifted and couldnt find my own signal again. someone on a local net said to only manually tune the downlink and let the uplink stay fixed but that doesnt sound right to me. also not sure if it matters but im running about 5 watts to a handheld yagi which has been enough to get into the bird most times i think

any advice from people who actually work these regularly would be great, im not trying to be the lid who blows through the whole passband

the way i do it — and this has worked pretty reliably for me on FO-29 and AO-7 — is to let Gpredict handle the downlink correction automatically via CAT and then i manually tune my uplink to keep my downlink signal where i want it in the passband. the reason is your downlink is what youre actually listening to and you want that to stay stable in your receiver, so automated correction there makes sense. the uplink you adjust yourself based on where you hear your own signal coming back down.

5 watts to a handheld yagi is honestly fine for most passes if you keep your antenna pointed reasonably well. the bigger issue people have starting out is not accounting for full duplex — if you cant hear yourself while transmitting you kind of flying blind. the IC-9700 should do full duplex natively so thats good. took me a while to get my doppler timing down but once it clicks it becomes pretty automatic, just gotta work a few passes and youll get the feel for it

yeah the Gpredict CAT control can be a little finicky depending on your rig settings, double check the CI-V address if it seems like its not actually moving the VFO. had that problem for like two weeks before i figured out i had the wrong address set and it was just not doing anything lol

also AO-7 can be weird because it switches modes depending on eclipse/sunlight and sometimes its just not in mode B when you expect it to be, worth checking the current status before a pass so you dont waste time