Hi, thanks for your response, this is what I found, but I still can not find a service manual, is there even one for this amp? There are two potentiometers, but still none the wiser what values they should be and where the test points are?
The standing current in the output stage can easily be adjusted to its correct value (which is not critical) by slightly adjusting the ratio of the two resistors in the base circuit of the transistor. For full power output from the amplifier the d.c. potential existing at the output of the amplifier proper should be as low as possible. This can be adjusted by the potentiometer in the base of Trl• If this is not done the amplifier will not be able to swing equally in the two output polarities.
The standing current in the output stage can easily be adjusted to its correct value (which is not critical) by slightly adjusting the ratio of the two resistors in the base circuit of the transistor. For full power output from the amplifier the d.c. potential existing at the output of the amplifier proper should be as low as possible. This can be adjusted by the potentiometer in the base of Trl• If this is not done the amplifier will not be able to swing equally in the two output polarities.
Hi, Yes I found that website, the bit I copied and pasted in that .pdf article comes from that page, that is the only mention of setting the bias up. So not very helpful. I was hoping someone might have a service manual, showing which potentiatometer to adjust and where the test points are. I will do some more googling, the amp sounds really good after the full recap with vishay sprague's it was a lot of work, but well worth it, a lot of the blue 25uf - 25V electrolytic's were bad. So decided it was safer to do all of them for reliability reasons.
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