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Checking for DC offset on 2238b

M

Majoryyz

Active Member
In the service manual, it says to read and adjust voltage in the power amplifier to connect the digital multimeter between R763(+) and R765(-) and adjust with trim resistor R731 to get 23mvDC. The other side of amp R764(+) and R766(-) and adjust trim resistor R732. My question is R763 and R765 are rectangular resistors as are R764 and R766. They are not pins. What I want to be sure is that I'm connecting to the correct location on the board to get the reading without shorting out the board. This receiver layout is different than a 2230 with separate amp boards. Can someone walk me through this? I can't load a photo of the P700 schematic, for some reason.
 
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Pete is correct.
Those are the bias test positions on the emitter resistor leads.

The dc offset is adjusted with R711and your test leads on J714&717 ,the other channel is R712 with test leads on J714&718.

J's are test pins on the board.

Bob
 
Thanks for the clarification. The manual doesn't say anything about bias test leads, but with your explanation, I got it.
 
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