Lexicon RV-8 Service Manual page 46

RV-8 Service Manual
Note:
During this procedure all tests are performed with NO INPUT SIGNAL applied to the amplifier inputs and
with NO RESISTIVE LOAD connected to the amplifier outputs.
Bias Adjustment On The 4 Channel Module:
Channel # 1
1. Measure the DC voltage across pins 1 & 2 of P11.
2. Adjust R84 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Channel # 2
1. Measure the DC voltage across pins 5 & 6 of P11.
2. Adjust R168 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Channel # 3
1. Measure the DC voltage across pins 1 & 2 of P12.
2. Adjust R252 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Channel # 4
1. Measure the DC voltage across pins 5 & 6 of P11.
2. Adjust R336 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Bias Adjustment On The 3 Channel Module:
Note:
The reference designators on the 3 Channel Module are identical to the 4 Channel Module, except
Channel #1 is eliminated.
Channel # 2
1. Measure the DC voltage across pins 5 & 6 of P11.
2. Adjust R168 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Channel # 3
1. Measure the DC voltage across pins 1 & 2 of P12.
2. Adjust R252 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
Channel # 4
1. Measure the DC voltage across pins 5 & 6 of P11.
2. Adjust R336 until the voltage measured is 350mV, +/-12mV (338mV–362mV).
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