I'm running Carl's Radio Kit choke now in mine and it works ok but I don't
have a 12M antenna so it really has not had a good work out. Also my
amplifier is a copy of a 77 and minor differences in the tank circuit will
alter the test data somewhat. Radio Kit's, or the original B & W 802 is a
better choice than the original 800 for current handling. The 800 is pretty
light duty even for a single tube model. It's only rated about 700 mA.
Also ETO removed 12 turns from the 800 to get the resonance off 15 meters
and nearer the Citizens' Band so it ain't much of a choke on 160.
All you guys who want to run your 77 on 12 meters ought to try the choke first.
It's expensive to install circuitry to 'switch' the rf choke in that big
rig. As Tom Rauch pointed out, series resonance points will move around
depending on proximity to objects in the RF deck. Ever play with a Tesla coil?
73, Dick
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