[Amps] AL-82 Zener problems

[Tom W8JI]

> grounds on the power supply board and also the diodes on 
> that board.  I
> also blew out the amp with compressed air to be sure there 
> was no dust
> causing anything to arc.  Tubes do not appear to be gassy 
> and the amp will
> put out full power.  The amp has Amperex tubes.  Any 
> ideas?


It's a tube Joe. It can't be anything but a tube, and what 
you see is typical of a marginal vacuum in a tube.

Once the tube "pops" it probably getters itself (arcs can 
clear the gas) just enough to hang on a while and it will be 
OK for a while.

73 Tom