I've enjoyed reading this list for some time, and
now have a problem I hope someone has visited before.
I recently came into possession of a Swan 6 meter
amplifier using 2 3-400Z Eimac tubes. In CW-Tune
low power position, amp seems to tune smoothly and
up to about 500w into a dummy load.
When switched to SSB (about 3kv Plate Voltage), upon
switching to TX (even with no exciter power), there
is about 200w output from amp, and tubes begin to
glow red pretty quickly. If I dramatically retune
Tune and Load from the positions I had in the CW
mode, I can get it to seemingly tune okay with power
at about 1000w. My issue is the take-off it has
with no input or even shorting the input. The amp
has what I guess is a neutralizing bar between the
tubes, but it doesn't work if the amp is taking off
on its own.
Anyone familiar with this amp or other amps that
might have had similar problems and fixes?
Thanks,
Bennett ko2ok
ko2ok@arrl.net
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