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Kenwood KA1030 audio amplifier problem

Hello again !

The amplifier mentioned in the title was gifted to me by someone who doesnt want to keep it because it is not working.
I am thinking to fix it and keep it as spare.

When i pluged it in it would not turn on and no LED'd in front panel came on. I opened it and found the mains fuse replaced by a wire.

I have located two power transistors burned Q34 and Q36 also R52, R54 and R64 burned. I have replaced them all with same value components (appart from Q34 which i used A1695 instead of A1694).
Now when i power it on the front panel LED's come on but within seconds it smokes R12. I have checked all tansistors and semiconductors around and found none damaged. Also i have checked Q10, Q12 and Q14 and are all good.

Any ideas ?

THANK YOU !

P.S. since i can not post PDF file, the service manual can be downloaded from here :
https://elektrotanya.com/kenwood_k_ka1030.pdf/download.html
 
Good idea. Here they are:

Also the picture Mainboard marked shows the location on the circuit of the components i found faulty and replaced.
 

Attachments

  • input board.jpg
    input board.jpg
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  • wiring diagram.jpg
    wiring diagram.jpg
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  • Main board.jpg
    Main board.jpg
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  • Main board Marked..jpg
    Main board Marked..jpg
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