Greetings all--
I have a couple of installed B&W 850A turret coil assy's in some homebrew
amps I'm resurrecting. One in use with 2x3-500Z, one with a 4CX1000A.
I have limited (in fact, nearly none) docs on the B&W 850A. The only
documentation I have, an old Radiokit catalog, states it so:
2000-4000 VDC
2500-5000 ohms (plate impedance)
80m L=13.6uH C=150pF to resonate
40m L=6.5uH C=80pF to resonate
20m L=1.75uH C=70pF to resonate
15m L=1.0uH C=55pF to resonate
10m L=0.8uH C=50pF to resonate
THE QUESTION:
80m and 40m look about right from the perspective of: (1) calculating
values for a plate resistance of around 2500 ohms; which is close to both
the 2x3-500Z and 4CX1000A plate impedances at my operating conditions; and
(2) relative scaling (i.e., 40m is half the value of 80m). 10m kinda looks
ok from just a raw calculation, but doesn't seem to scale well.
BUT 20m and 15m just look whacked. The 20m and 15m calculations puts
loaded Q around 16 or so, which seems unreasonably high.
Can someone supply either or both of the following:
1. B&W 850A specs, in the event they were misprinted in my Radiokit catalog.
2. Any explaination of where I turned stupid, or perhaps where it's
generally known to the community that B&W turned stupid.
Many thanks in advance for eliminating at least my own ignorance!
------------
Scott Townley
Gilbert, AZ
nx7u@primenet.com
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