so I recently swapped out the power tube with an RCA I got from eBay. it worked well for a while now i have the issue of the amp providing no sound when turned on. the tubes warm and turn on.
so I just need help troubleshooting the issues.
put old tube back in as first step to see if it works then.
ok just got back from class and the same problem exists with the original power tube, no sound but the heater coils turn on.
Was the tube you call and RCA the proper type that is supported by the amp?
If not it could cause issues with the amp…then the orignal tube might not work as well…
???
I got the 6as7g tube for the replacement power tube, and it worked for a few days and then when i turned it on it didn’t output sound anymore
ok if its a supported tube and it worked then several things could have happened.
Tubes good or bad can “short” out and cause issues at any time.
If this happened it could take out a component like a grid resistor and then the circuit will not function.
Was there any burning smell at all from the amp?
The glow in the tube is an indication that the voltage is heating up the filament but the tube wont operate if all the other stuff is not working as well…
I didn’t smell anything but there was what I think was a blue flash from the chassis, ( i had issues with the last power tube going out on me, during testing it didn’t have those same problems) I was suspecting that a resistor went bad but have no idea where to begin testing
Blue flash could be a short. Shorts will cause a large current to flow and could destroy a component, if for several seconds then things could fry, burn and smell…
If i happens fast maybe not but still could hurt a component.
Is there a “fuse” in this unit?
The heater filaments are either AC or DC, depends on the design…so the tube can light up get hot but not work due to the other failurs.
I would check WITH POWER OFF all the attached components to the tube socket for damage. You can gently tug on them and a bad resistor might come apart with a small tug…be careful
If your not inclined to do this take it to someone that can repair stuff SAFELY.
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