Please assist me in bellow written topics to reapir/stage amplifier.

Thread Starter


Joined Jan 18, 2017
Dear seniors & all forum members, please help me in bellow written topics: I have one old 80watt trolley type stage use amplifier, its USB board became faulty, to replace this I arranged one USB board. This board consist of two 8002B (2watt) power amplifier made stereo output (BTL) channel; speaker connected to terminal 5 & 8. No one output terminal is connected with power supply common/ground. It means for two channel there are 4 wire.
Now, the power amplifier I have that is 3 wire input from original USB board (R, L& G common). I traced its input control & it is like this:upload_2017-1-18_11-37-2.png
Please suggest me how I will figure out its connection from new USB board to amplifier input ckt. Thanks in advance.


Joined Oct 29, 2009
Thanks, sorry for late as I was outside.

Interesting. Now if you can post some information that will help to answer your original question. Like what are you trying to do? Why are you trying to connect an audio amplifier to a USB connection? What could you possibly be trying to amplify? I hope you are not risking using the USB port for a power source only.