mpr2000
Active Member
I'm working on a 2265 that's a little rough - internally. Looks like several people have been inside over the years. I've gone through it and swapped out all the caps on the P800 PS board and the P700 Amp boards. The PS board had a bad 2SC945 (HB03) and an open resistor.
The amp board outputs were bad on one side along with a few resistors. All transistors were pulled and tested - and tested okay. Emitter resistors were replaced, multi-turn pots installed, etc. Outputs on both sides have been replaced with MJ21193/MJ21194's.
Here's my issue. On one channel, I am getting 28vdc at J713 below (output). Not good. The other channel is fine, and if I pull the wire at J713 on the bad channel the protection relay works, etc. J706 is 35vdc in to the board. All wiring has been triple checked, I pulled the outputs and retested, then reinstalled and checked for mounting shorts. All diodes were tested (in place) on the board. Replacement cap polarities verified, etc. I'm just starting to work my way back from J706, but wanted to see if anyone had any thoughts.
One board "rebuilt" and as it went back in the 2265:
The amp board outputs were bad on one side along with a few resistors. All transistors were pulled and tested - and tested okay. Emitter resistors were replaced, multi-turn pots installed, etc. Outputs on both sides have been replaced with MJ21193/MJ21194's.
Here's my issue. On one channel, I am getting 28vdc at J713 below (output). Not good. The other channel is fine, and if I pull the wire at J713 on the bad channel the protection relay works, etc. J706 is 35vdc in to the board. All wiring has been triple checked, I pulled the outputs and retested, then reinstalled and checked for mounting shorts. All diodes were tested (in place) on the board. Replacement cap polarities verified, etc. I'm just starting to work my way back from J706, but wanted to see if anyone had any thoughts.
One board "rebuilt" and as it went back in the 2265: