ORIGINAL MESSAGE:

Straydog wrote:

there must be forced-air directed upwards from the non-tube side of
the tube socket and there are specifications for flow rate and
pressure.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Flow rate and pressure" are nice, but the *only* important thing is
the temperature of the tube at various points as specified by the tube
manufacturer. If you are serious about proper tube cooling, use either
a non-contact thermometer of some kind or thermally-sensitive paint to
ensure your tube is within temp specs. Flow rate and pressure are a
means to an end, not an end in themselves.

Bill, W6WRT