Thank you very much for your help. I've already managed to repair power sections and power amps. Now all that's left is the lack of sound. If I give the irfp264 driver a direct signal from the speaker generator game. The signal disappears somewhere near the master / slave switch. It's hard for me to locate the exact signal path in the preamplifier. I have replaced all TL074 and TL072 integrated circuits but nothing has changed. Does anyone have a preamplifier? Later on, I will add some photos that may be useful in the future. Thank you again for these photos. I also have several other technical documentation, if you please, please contact me for a private message.
There is nothing on Pin 11. If I give a signal at 11 pin, the amplifier works. It disappears somewhere near the last TL072. The resistors all checked the capacitors too, the integrated circuits also listed and still silence. Previously, someone has already pushed in the amplifier cut through the tracks on the disc, etc. The signal was bridged I would like to do it as it was originally.
I've corrected the changes that somebody was doing badly. All thanks to the kindness of my friend ppali. The problem lies in the DS1808 system volume control. All control signals come to him. SDA SCL and CE. There are waveforms visible on the oscilloscope. During changes, the potentiometer of the external bass controller. However, the signal does not go from pin H0 to W0. Because of this, there was no signal at the exit. It looks like there is MUTE -90dB there. If I am bridging H0 with W0, the amplifier works correctly. It would be up to me that this external bass driver would work.
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