Rockola 490-1 amplifier center voltage and current adjustments
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Working on a Rockola 490-1 I had to do repairs to the amp as well as it had a flaky bias current adjustment pot so I replaced all 4 pots. Trouble is the manual for the 490,490-1 doesn't include the adjustments mentioned on the plate in the amp. Does an earlier model use this amp and the manual give the adjustment procedure? The amp is 54510-A
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MattTech
- Senior Member
- Posts: 1461
- Joined: Tue Apr 29, 2008 7:38 am
- Location: Philadelphia Pa USA - Home Electronics - Service Technician
Centering voltage is usually the result of half the supply total B+ measured from ground to the output emitter resistors junction.
Bias for perhaps 10mv at the test socket.
Piece of cake.
Bias for perhaps 10mv at the test socket.
Piece of cake.
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