[Amps] TL922-one tube dead

[David Lisney]

Hi, I have a TL922 but not yet seen the inside of it! However it is never a 
good idea IMHO to worry about spares before the extent to the damage is 
know. Since one tune is still lighting up and drawing roughly the correct 
current it suggests to me that the other tube has not badly gone wrong 
either.

I would personally be inclined to check that the second tube still actually 
has heater volts on the pins, the 3-500 is fairly greedy on heater current 
so it is possible the socket has arced a bit and lost contact with the pin 
of the valve.

Perhaps you can swap the valves over with each other to see if the fault 
moves with the valve, also a chance to clean up the pins.

The price of these valves is sufficiently high I think you would be well 
advised to test all the obvious things first.

Regards David