Help with SSL 4K touch sense circuit problem

Hello forum!

Our 4000 G+ SE console has fader which dosen't move motor at all. Sad panda.

After short probing I noticed touch sense hybrid H1 is feeding +5V all the time from pin 2 (out+) and thus disabling motor powers. Pin 3 (out-) is practically dead.
I couldn't find schematics from my manuals and now I'm stucked.

I've read there's few different versions of H1 but I don't know what's mine so please see pictures I took.

http://www.5by5.fi/diy/ssl4k/ssl_h1_front.jpg
http://www.5by5.fi/diy/ssl4k/ssl_h1_rear.jpg

Control board has been modificated: in place of C15 is LM78L05 feeding juice to hybrid pin1 (trace has been cutted from normal +5V) and pins 5 and 6 are disconnected. For me it looks there's variable capacitor in H1 instead C15.

All help and info specially theory of operation and schematics would be very cool.

Thanks in advance,
Paavo

With hint of luck and few hours of testing component by component I finally found fried fet TR1 from H1. No more sad panda 

Anyway I'm still looking schematics and calibration procedure for VC1.

Cheers,
Paavo

Well done!


Mattia.

Cheers mate!