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Yamaha M-4 | Relays not connecting after recapping

Cergei said:
According to the manual TR-220 is a small black transistor
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Not TR-220.. TO-220 case style. Which are TR414 and TR416 mounted to the large heatsink.. One is black and one is green..

TO-220 case style

1a6b1599-2526-4b9d-8af7-efc7b5bf5aa1_1.0bb2acfe2a2967c683c75434f68fee58.jpeg
 
Hi, thank you for the clarification. Understood now which transistors. Should I measure between E (common negative ) and each Base, Collector and Emitter ?
 
avionic said:
Please elaborate a little more ..
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I said sound is back because after re-soldering some transistor connections on the pre-drive board there was no output at that channel (Right), no Vu meter indication neither. After cleaning, removing some excess of solder got back output signal, but sound was not clean, but a little distorted. Now I am at work for several hours, away from home where the amp is.
 
I am not having any sound at the speaker output (right channel), nor indication on the VU meter and some warm temperature on the drive board in the indicated area, any clue?


Warm-temp-area.jpg
 
I disconnected the power from pre-drive board and also unplugged the connector between pre-drive and drive boards and that fuse resistor FR-404 raised temperature. Then power off the unit.
What else should I check ?
 
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