Not just the Tx valves, all the valves from the
synthesiser
on were protected, the exception was the audio pre-amp which
were the cause of > 50% of shutdowns until replaced by solid
state units.
If anything, the a slow power-up is probably
protecting the
power supplies more than the tubes.
Not in these transmitters.
I am talking specifically about tubes in computers, not in
transmitters. Transmitter tube care is a different ball of wax.
New valves are always run for the guarantee life,
modern valves
are very poor, more than half are either DOA of fail within
the guarantee period.
The 1970s were the beginning of the end. Most modern tubes suck.
William Donzelli
aw288 at
osfn.org