so ive been trying to work FO-29 and AO-73 for a few months now with a handheld yagi setup, nothing fancy, just a pair of Arrow antennas and my FT-818 doing the uplink and an SDR for the downlink monitoring while i tune. the passes are short enough that by the time i find my own signal on the downlink and correct for the doppler im already halfway through the pass and fumbling with the radio. feels like im chasing my own tail every single time.

the doppler correction is the part that kills me. i know the math, i get that the uplink and downlink shift in opposite directions on a linear transponder, but doing that in real time while pointing a yagi and trying not to spin around like an idiot in the backyard is just... a lot. ive been using gpredict for tracking and it helps but the manual tuning is just brutal. does anyone actually do this without some kind of computer-aided doppler correction? or am i just supposed to accept that the first minute of every pass is basically wasted getting set up?

also curious whether AO-73 is even worth bothering with right now, ive heard its been in power saving mode a lot. FO-29 seems more reliable but the inverting transponder thing still messes with my head when im trying to hold a qso.

yeah the first minute is basically always wasted, dont feel bad about it. even with a full az/el setup and gpredict driving the rig via hamlib it still takes me 20-30 seconds to get oriented when the sat comes up. the difference is at least im not also fighting doppler manually by then.

the inverting transponder thing on FO-29 just takes repetition honestly. you tune up on the uplink, signal goes down on the downlink, brain eventually accepts it. what helped me was just spending a few passes not even trying to work anyone, just listening and watching how my signal moved. also USB on the downlink pretty much always even though youre sending LSB up, thats the rule of thumb for inverting transponders and once it clicks it clicks.

AO-73 has been frustrating lately, youre right to be skeptical. stick with FO-29 for now or look at the SO-50 passes for FM just to get reps in on tracking without also fighting the linear transponder learning curve at the same time.

im kind of in the same boat as you, been at it since last winter with an Arrow and a 705. what actually made a big difference for me was setting up two separate VFOs and just pre-loading the center frequencies with rough doppler offsets before the pass starts, like i know where im going to be at AOS, mid pass, and near LOS so i just step through manually at those points instead of trying to continuously tune. its not perfect but its way less chaotic than chasing it in real time.

gpredict with hamlib is on my list to get working properly but i havent had time to sit down and configure it right. heard it can be a pain with certain rigs depending on the CAT setup.