so this has been going on for maybe 3 weeks now and im at my wits end. the radio transmits fine for anywhere from 5 minutes to half an hour and then just... drops out. carrier goes away, ALC goes flat, no RF out. receive is totally fine the whole time. if i key up again it sometimes comes back immediately, sometimes takes like 30 seconds of trying. no error codes on the display which is the frustrating part.

it doesnt seem to be heat related - i had a fan blowing on it last weekend and it still happened. also doesnt seem tied to power output level, happens at 50 watts same as 100. ive already reseated all the internal connectors i could get to without pulling the whole PA board. voltages from the supply look solid on a meter, sitting at 13.7 no load, barely drops under TX.

wondering if anyone has seen this specific fault or has a direction to point me. im reasonably comfortable with a soldering iron but dont have a scope which probably limits what i can diagnose without help.

had something weirdly similar on an older 7200 years ago. turned out to be a bad solder joint on one of the driver stage connectors - not obvious visually but just enough movement under thermal stress to break connection. the intermittent nature and the fact that it sometimes comes back after waiting sounds a lot like that kind of marginal joint rather than a component that's actually failed hard.

if you can get the PA board out and hit it with good lighting and magnification, look around the connectors and any through-hole components near the PA section. reflow anything that looks even slightly suspect. also worth checking the ALC feedback path - if that's going wonky it can effectively shut down TX without throwing a fault because the radio thinks it's protecting itself. without a scope it's gonna be tough to chase the ALC signal but you can at least verify the DC bias points if you can find the service manual voltage charts.

does it happen more on certain bands or pretty random across the board? asking because i had a 7300 that would cut out on 10m and 6m but work fine on HF and it ended up being the LPF relay switching - one of the relay coils was getting flaky. totally different symptom pattern than yours but just figured id ask before assuming its the PA.