Harold Mandel wrote:
> Dear Rick,
>
> When tweaking my dual 3CPX1500A7 amp under the RF deck what I did was
> to fabricate a piece of 1/8" thick Plexiglas clear plastic in the same
> fashion as
> the lower plenum cover with the addition of tiny holes I drilled for the
> insertion
> of screwdrivers and meter probes, leaving them taped over wit painter's tape
> until I needed to accesas the holes.
>
> That way I could pressurize the plenum to my heart's content without fear of
> trashing my $2800 tube set.
If the only adjustment you need to make is to the heater voltage, add a
couple of feedthroughs or similar to the cathode compartment wall and
connect them to the heater via 10k resistors. Using a DVM to read the
voltage the error will be minimal, and there's no risk of any harm if
you accidentally short either to chassis.
Steve
PS the devil in me wonders if you can run the heater without air for as
long as it takes for the seals to reach maximum allowed temperature?
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|