ToniCH
Well-Known Member
Hi guys,
Just bought a AU-9900 today. Before testing I checked DC and Bias current.
On one channel DC was ok and on another not ok. So, I adjusted the DC per service manual and now both are ok...ish... One channel is steady and another jumps around about +-10mV but stays quite good within specs.
Next Bias: well, here is the problem. Manual tells me to measure mA and adjust to 50mA. I am getting something like 0.3mA and neither channels reacts to adjustment.
What is the most probable problem and where should I start troubleshooting? Thanks for any suggestions.
BTW. I briefly tested it with junk speakers to see if it works at all and yes, it plays music. I didn't feel anything getting very hot while it was running either.
Just bought a AU-9900 today. Before testing I checked DC and Bias current.
On one channel DC was ok and on another not ok. So, I adjusted the DC per service manual and now both are ok...ish... One channel is steady and another jumps around about +-10mV but stays quite good within specs.
Next Bias: well, here is the problem. Manual tells me to measure mA and adjust to 50mA. I am getting something like 0.3mA and neither channels reacts to adjustment.
What is the most probable problem and where should I start troubleshooting? Thanks for any suggestions.
BTW. I briefly tested it with junk speakers to see if it works at all and yes, it plays music. I didn't feel anything getting very hot while it was running either.