[R-390] Rats - There goes a pair of 26Z5W's

[David Wise]

Probably blew up the filter caps.  B+ rises in Standby because
the load is smaller.  If the caps were old and used to the nominal
B+, they would conduct greatly increased leakage current
when it was high.  As they warm up due to the increased
power dissipation they leak more.  Hotter, hotter,... SHORT!
Better check them before you replace the rectifiers.

73,
Dave Wise

> From: Barry [mailto:N4BUQ at aol.com]
> 
> simply been the tube's time to go.  I had inadvertently left 
> the radio in
> STDBY for about an hour and a half while the PTO was warming 
> up for the test
> (meant to switch to AGC but forgot).  Perhaps this placed 
> some sort of odd
> strain on the rectifiers.  I don't know.