What are they connected to in the circuit?
Tantalums can become leaky (electrically). They have a fairly high failure rate in the preamp section in Orion amp. I've never seen them fail where you have them circled. If they have, it may be time to start recommending that every electrolytic cap be replaced in these amps, due to age.
Tantalums can become leaky (electrically). They have a fairly high failure rate in the preamp section in Orion amp. I've never seen them fail where you have them circled. If they have, it may be time to start recommending that every electrolytic cap be replaced in these amps, due to age.
I mention before the amp has been intermittently shutting down. Last night it started shutting down again. I found that just before the amp shuts down the voltage on pin 4 of the 494 would start rising and when it neared +4.0v the amp would shut down. While the amp is shut down, the voltage on pins 8 and 12 of the 494 drop to 10.0v DC. I didn't get a chance to check anything more as the amp powered back up and since hasn't shut down again.
With the amp sitting at idle, I did find that the 6488 circled in the photo was getting pretty warm, not hot but definitely heating up. I replaced it along with the one next to it. The new one is warming up just as the old one did. Do you have an idea of what could be causing it to heat up or is that normal?
Also noticed with the amp sitting at idle (not clamped) that the PS FET's circled in the photo are getting slightly warm where as the other PS FET's are not. Not sure if that should be of any concern...
My thoughts are that whatever component is causing the amp to intermittently shut down is also causing the voltage on pin 4 of the 494 to be above 0.0v. Not sure if changing those 6488's had anything to do with it or the amp just doing its oddball stuff but the voltage on pin 4 now drops to 0.70v after the amps sits running at idle for a few minutes.
With the amp sitting at idle, I did find that the 6488 circled in the photo was getting pretty warm, not hot but definitely heating up. I replaced it along with the one next to it. The new one is warming up just as the old one did. Do you have an idea of what could be causing it to heat up or is that normal?
Also noticed with the amp sitting at idle (not clamped) that the PS FET's circled in the photo are getting slightly warm where as the other PS FET's are not. Not sure if that should be of any concern...
My thoughts are that whatever component is causing the amp to intermittently shut down is also causing the voltage on pin 4 of the 494 to be above 0.0v. Not sure if changing those 6488's had anything to do with it or the amp just doing its oddball stuff but the voltage on pin 4 now drops to 0.70v after the amps sits running at idle for a few minutes.
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