Restore + Repair Yamaha C-2a & C-80 / M-80

TR05
D = +4.2V
G = 0mv
S = + 822mV
/
S = +850mV
D = 0mV
G = +4.1V

TR06
D = +3.26V
G = 0mV
S = + 550mV
/
S = + 528mV
D = 0mV
G = +3.24V

I guess these look okay...
 
I'm pretty busy today. I probably won't be much help. Possibly Patrice will pop in. The Right channel was working OK, wasn't it?
 
I'm pretty busy today. I probably won't be much help. Possibly Patrice will pop in. The Right channel was working OK, wasn't it?
I have not tried to listen to it since the onset of new problems... but yes, the original symptoms was that the right channel would drop in stereo but both channels had sound in mono. I'm pretty sure I don't have sound in either channel right now though?

No worries about helping today. I'm just posting the readings so it's available and I had some time this morning. I have some other things I can work on. Thanks for your help yesterday.
 
I still have TR527-530 out of circuit... I was waiting for @clinic-audio to look at the voltage readings...I'm not sure if the left channel is still working...

before when 527-530 was in circuit there was smoke and resistors were burning so I'm not going to put them back in until someone says to do so or I have a good reason to put them back in...
 
I am back

can you check the deleted transistors ?

As Dave asked , is left channel working ?
Hey Patrice, welcome. Thank you for your help.

How do you want me to test the transistors? out of circuit with a diode test?

If I put them back in I am afraid things will start smoking...
 
the other ones measure good i think but the pin out does not match the legend on the schematic
 

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USING DIODE TEST:

red/+ on B

C = .0035
E = .0029

black/- on B

C = .0035
E = .0029
 

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I'm not sure about TR530..

red/+ on B

C = OL
E .5879

black/- on B

C = OL
E = OL

Is it shorted between the base and collector?
 
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