Finished assembling my Pearl 2 yesterday. I started it up with a variac and when I got to about 50% it blew the fuse. Replaced fuse and put a multi-meter on the output and got lots of voltage on the output (2 volts before shutting it down).
I'm using an XLR connector for voltage between two chassis and didn't understand that the shield connected a pin and the sockets. I clipped the wire going to the sockets thinking I had solved my problem.
Started testing again today and am still getting negative voltage on the output (both boards behave the same). Almost as much voltage as is going into the board itself. I have done a lot of testing to make sure I don't have any shorts in the wiring.
I pulled one one board and can't find anything out of place. I'm stumped at this point.
I'm using an XLR connector for voltage between two chassis and didn't understand that the shield connected a pin and the sockets. I clipped the wire going to the sockets thinking I had solved my problem.
Started testing again today and am still getting negative voltage on the output (both boards behave the same). Almost as much voltage as is going into the board itself. I have done a lot of testing to make sure I don't have any shorts in the wiring.
I pulled one one board and can't find anything out of place. I'm stumped at this point.
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Looks like Q2 is fully turned on or oscillating, remove C7 if fitted, if that doesn't fix the problem, replace the ZVP3310 - is very sensitive to static.
Need voltages at all 3 pins of Q4, Q11 and Q10.
Does twiddling P1 have any effect on the 0 voltage point?
As much as it seems like a good idea at times, it actually doesn't fix the problem at hand.
Does twiddling P1 have any effect on the 0 voltage point?
As much as it seems like a good idea at times, it actually doesn't fix the problem at hand.
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I believe that's known as "percussive maintenance"! It often works as a last resort.
I hooked it up to the stereo system and it plays at normal levels now but I don't dare to run it long because Q11 is so hot (touching it for a few seconds becomes uncomfortable).
Could it be the wrong LED (not the same in both channels). I bought the one in the bad channel from Radio Shack thinking a red LED is a red LED.
Could it be the wrong LED (not the same in both channels). I bought the one in the bad channel from Radio Shack thinking a red LED is a red LED.
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