> So not only has it been exposed, as long as the
> fan was running it probably had nice humid salty
> air being forced to flow around it.
I recall several MLA2500's we used at various Carib multi-op's in the
80's and 90's that could not be turned off after a few days of running
because of salt build-up on the ceramic part of the tubes directly in
the airflow of the fan. They ran along just fine as long as they stayed
on. Once you turned them off, restarting them would cause HV to arc
from the plate structure to the ground ring at the base - easily a half
inch of ceramic. The arc would destroy the plate voltage over-current
protection resistor and require a disassembly of the PA. One would also
have to pull the tubes and wipe them down with a damp rag. Once the
failure mode was figured out, we simply left the PA's on for 2 weeks
Those MLA's were in accelerated stages of chassis corrosion after 2 trips.
(VP5KMX, VP2V/K9GL, J87J, ect)
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