Kenwood KA1030 audio amplifier problem

[HellasTechn]

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

 

[dave9]

Screenshot the PDF or print to image to post schematic.

 

[HellasTechn]

Good idea. Here they are:

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

 

[HellasTechn]

No ideas?

 

[kellys_eye]

it smokes R12.

sure it's R12?

 

[HellasTechn]

Yes. but i will triple check just to be sure.