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IC-7300 putting out maybe 20w max, driver stage issue?

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so this has been driving me nuts for a couple weeks now. picked up a used 7300 off a local ham who said it was working fine, and maybe it was, but when i got it home and threw it on the dummy load the power output is just sad. ALC looks normal-ish on the meter, all bands affected, no smoke smell or anything obvious. gets warm in the usual spots but not like its thermal shutting down or anything.

pulled the cover and did a visual, nothing obviously cooked. im thinking driver stage but honestly i dont have a ton of experience digging into these SDR rigs vs the older stuff where you could kinda trace signal path more intuitively. anyone gone into one of these for a similar symptom? wondering if its worth pulling the finals to check or start somewhere upstream first. i do have a scope and a decent RF probe if that helps narrow down where to look.

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before you start pulling finals i'd check the PA bias voltage first, thats caught me out before on a similiar icom. there's a trimmer on the PA board and if someone's been in there messing around it could be way off. also worth checking if the ALC is actually clamping things down for some reason — sometimes a bad connection on the mic jack or something dumb like that will make the radio think its getting audio feedback and it just throttles everything. hook up a known good dummy load if you havent already and watch the ALC line on a scope while you key up. might save you a lot of disassembly if its something upstream.

had almost the exact same thing on mine, turned out to be one of the driver transistors was intermittent. not fully dead just kinda... tired i guess. output was like 18-22w depending on band and temperature. the finals themselves tested okay when i pulled them. ended up replacing both driver transistors while i was in there since they were cheap enough and didnt want to do it twice. icom's service manual has the bias setup procedure, its not too bad if you have a power meter handy. good luck with it, these are nice radios when they're working right.

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