On Fri, 5 Oct 2018 17:54:06 +0200, Steff wrote:

Well just lost a channel at my Harman Kardon 930 Vintage geek as I am I
want to keep my great Reciver and repair it..

What I done sofaar

Check Fuses ( They are OK)
Moving the speakers between the channels left-Right And A and B speaker
outlets.

With this info I understand that the left Channel is ALMOST dead turning
the balance to Left channel I can hear a faint OK sound. (Like the tiny
transistors trying their best before the end power transistors do their job.

My conclution.

1 Not enough power to the end transistors on the left channel.
2 Broken End Trasistors (two 2SC897 according to the scematics)
3 End of preamp broken on left channel.


Most likely End transistors..

Is my thinking OK or did I miss something ?

I am a beginner in HiFi electronics but have basic skills in electricity
as an electrician for 25 years and do know how to solder..
Try pushing the tape monitor and other push button switches on the
front panel a few times to see if the channel comes back. If it does,
spray the switch with DeOxit 5 or equivalent.