I was gonna suggest perhaps C61 is shorted to ground but it says you already replaced it.

Maybe start probing around and try to find where that portion of the circuit has continuity to earth.

 

Anyway I'm out I shouldn't be "contributing" to these fix it threads 

Today I had to make a parallel circuit with a variable resistor

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Then do some calculations etc for voltage drops and calculate how many ohms the variable resistor should be for Va to equal Vb

Then make the circuit and do it

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So yeah pretty boring but it's definitely helping I have to chug through this in order to get to the cool stuff.

Pretty funny the book noted "although Vo can be directly measured across A and B it is good practice to make all measurements with respect to ground"

 

Quote from: markorock37 on May 02, 2024, 07:49:32 PMT3 pins 1,2,3=C,B,E
T5 pins 1,2,3=E,B,C

As far as I know, there is no such thing as CBE pinout for these.  But, apparently there are 2 versions of each, and could be either EBC or ECB.
Can you post a link to the exact ones that you bought?

The other thread ended with Q8 catching on fire and no resolution.  It's better if you just tell us what is going on with your amp.

You can monitor the voltage across R97 (one probe at each end).  If you see more than 5VDC, stop.  As you move the variac voltages may jump around so give it a couple seconds to stabilize.
Also keep checking for DC at amp output.
If you are seeing low current on the variac meter, you should be ok to raise the voltage.

I am measuring current as well, so far it stays very low. I'll try upping the AC voltage today. I'm just worried about R97 burning up, or Q4 shorting again. What do you think I should look for next?
Also, what I am experiencing is almost identical to this post: https://www.ssguitar.com/index.php?topic=4235.msg42173#msg42173
Thanks again for the help

Well shoot. I was assuming the same pinouts as T1 and T2. Here it is corrected.

T3 E -40.6v
   B -40.6v
   C -40.1v

T5 E 0.6v
   B 39.0v
   C 31.4v

T3 pins 1,2,3=C,B,E
T5 pins 1,2,3=E,B,C

Thanks for the quick response!!

see attached

Again, voltages that are impossible for e,b,c locations.
Is it another mistake, or is it possible you have some transistors in backwards?

Looking for schematic for Crate Gunnison acoustic amp