Tackling a Beast (KR-9600)

[goldswimmerb]

Currently working on a KR-9600, going to the mod for saving the power switch with a triac once I get it sorted out.

On arrival there was no relay click, chased down to a bad power supply transistor. Following that the relay clicked in and FM at least started to show tuning. Now what I am seeing is no audio from the Preamplifier section. Running a source to the power amp in gives me clean audio, from any of the inputs, including FM I get nothing. The jumpers are in place as well. I can very faintly hear my aux source but it seems the preamp isn't passing signal in either channel. Bother +B and -B are there so I am somewhat stumped

 

[goldswimmerb]

So, investigating further, I am missing my 10v on the reed relay coil pin. The 3 transistors I can tell are directly associated with switching here check out good, and the 2SA733 reads 34ishv E and 33.5ish B, but no voltage on C

 

[Watthour]

For clarification, are both power relays closing?

Is there a mute signal applied at the power supply board?

 

[goldswimmerb]

Got it sorted, had a bad 2SC945 at Q10. Not a usually one I see bad.

The FM tuner has issues now where it's going into muting when center tuned but will play very crunchy when off tuned. Guessing I've got a bad HA1137 or LA1222...

 

[goldswimmerb]

For clarification, are both power relays closing?

Is there a mute signal applied at the power supply board?

Yeah the output relays were closing, was an issue with that muting reed relay circuit. Got it sorted, just and to sit down and work my way through the circuit.