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ARC Reference 150 Tube Biasing Issue

Installed new tubes for my ARC Ref 150, and the bias voltages look pretty weird. When I set the bias for 65 mv on the power tube, the slave tube shows voltages in the NEGATIVE 65 mv range. Two of the tube pairs do that. The other two pairs show voltage around NEGATIVE 90 mv on the slave tubes. Any one have any ideas what might be causing this?
scottwsmith

Showing 1 response by zd542

zd542
5,339 posts
 
"When I set the bias for 65 mv on the power tube, the slave tube shows voltages in the NEGATIVE 65 mv range. "

You just use the absolute value. You can't have -65mv. What kind of DVOM do you have?
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