UPDATE:
Thanks everyone for the assistance ..
Much learned.
Funny how you learn or assume something incorrectly and it gets stuck in
your head for many many years... that applies to this.
I knew the plate dip symptom was a loading issue and "thought" that
minimum cap was minimum loading .. have thought that for awhile now ..lol
( or just old age getting the best of me AGAIN ! )
I was HAPPILY mistaken .. thanks to everyone's help .. so I cranked up the cap
and re-tuned ..
Got about 1100 W for .550ma plate current, 3400 VDC ..
The thing is .. this watt meter is O L D .. and not sure how accurate it is ..
Though .. it does seem to read peak .. cause key down and dits give me the same
reading.
Must be close cuz the 1 KW dummy load is giving me the evil eye .
The tubes are running cooler and smiling now instead of grunting .. LOL
Still not sure what the max drive is .. though I was told the grids current was
ok at around 330ma
with 660 ma of plate current ..( grounded grid ) and I am not there yet .. and
the rig driving it is running off a car battery
( which is down to about 11.8 VDC now ) so ....
not at full power or near max grid current .. so I am assuming I am ok so far..
and 1 KW out is plenty ..
No sense in ruining the tubes for a db of improvement that cant even be heard
on
the receiving end ..
The plate and loading controls .. well mostly plate .. seems to be somewhat
repeatable .. close enough ..
The amp seems to be design such that not much loading is needed? or is that
just
because I am on the lower
freqs .. like 80 and 40 .. and using the dummy load?
There is receiver "hash" type noise on 160 meters when I engage the HV .. ideas
??
Thanks again all ..
Randy - N2CUA
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