so ive been chasing this one for about two weeks now and im starting to lose my mind a little. my IC-7300 is only putting out maybe 30-35 watts on 20m when its set to 100w. it does this across most of the HF bands, slightly worse on 10m where i might get 20w if im lucky. 40m seems a bit better but still not right.

before anyone asks — yes i checked the power output menu, yes ALC looks normal, i already reseated all the connectors i can get to without full disassembly, antenna is fine (ran it on a dummy load and same issue), and the finals arent running obviously hot. the radio was working perfectly fine like six weeks ago and i didnt change anything i can think of. just turned it on one day and noticed the output was way down. no smoke, no weird smells, nothing obvious.

thinking it might be one of the driver transistors or maybe a biasing issue but i really dont want to just start swapping parts blind. anyone been down this road with one of these?

had almost the exact same symptoms on a friends 7300 last year. turned out to be one of the RD70HVF1 finals had gone soft — not fully dead, just degraded enough to pull the output way down. what threw us off for a while was the ALC looking normal, because the driver stage was still doing its job fine, the final just wasnt amplifying properly anymore.

if you have an RF probe or a scope you can get a rough idea of whats happening at each stage. check the drive level going into the PA board and compare that to what youre actually getting out. if the drive looks right and the output is still low, youre probably looking at the final transistors. icom uses matched pairs in there so if you replace one you should really do both. parts are available, not super cheap but not crazy either. the bias trim on that board can also drift but id check the transistors first.

this is maybe a dumb question but did you check the firmware version? there was some weirdness with a particular version causing ALC behavior to go a bit off, i vaguely remember something about it on the icom reflector. probably not your issue but took me an afternoon once chasing a hardware fault that turned out to be firmware being weird after a partial update.

also worth pulling the top cover off and just having a look at the PA board for any caps that look even slightly domed. had a different radio (7200 actually) where a cap on the PA board had started to go and it caused intermittent low power that eventually got worse. not saying thats it just something easy to check visually before you go digging deeper.