Im guessing I got lucky. I tested the 4 power transistors on board F-3114, and now I am in the process of desoldering each transistor on the drive amp board F-3074, testing, then resoldering. So far I am at transistor 5, they all have been good so far. Should I continue with all 13 on this board? Are you convinced that something broke when that arch happened?
You do not need to remove TR09 and TR10 to measure them, and you do not need to test any other transistors on the F3074 board.

You got lucky, you just shorted the DC power rail momentarily.

Where were we at before the "accident" happened?
Have you checked all the fuses?
 
TR10 is no good. Just took it off just to make sure and still no good, basically getting 0 v drop. Ordering new TR10, are there specific fuses I should look for or just all over?
 
where are you getting a 2SA968 from? As I said they are no longer available.
Just check with us before you get anything off ebay, there are a few genuine one out there but you have to know what your looking for.
OR just to get the amp going, you could use a MJE15033, this will work, but you really need the right one to get the best performance from the amplifier..

and just to be sure, the transistor is definitely shorted? you get 0.000mV when you are testing which junctions?

Just have a look at all the fuses and see of any of them are blown.
 
Parts came in, do you know if thermal paste goes on both side of the plastic sheet or only one side?
 
Gotcha. I put the new transistor on the board. I will put the board back in the receiver later tonight.
 
Parts came in, do you know if thermal paste goes on both side of the plastic sheet or only one side?
I hope there is no plastic sheet in there, I would hope its a Mica Insulator.
You would apply a small amount of thermal paste to both sides, "a little dab will do ya"....
 
Installed the board and now the tr09 after a couple seconds of being on make a small pop and started smoking. I turned unit off and removed the board, tr09 has a visible crack on it. I turned down bias adjustment down before turning on fyi. Do you think this could be from the previous accidental short or something completely different?
 
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