The real problem is that in band switching a common-cathode
triode amplifier it is important to keep the output circuit balanced
so that neutralization may be maintained. Has anyone seen
a band switched push-pull triode amplifier? All that I have
seen have had plug in coils. The other problem is that the
outputs are always link coupled. So if one has tapped center
tapped tank coil he would also have to have tapped link
as well to maintain 50 ohm output impedance. So far I count
3 wafers on the switch for the plate and for the input.
The big Crosleys at VOA had a very long hair pin plate
tank ckt. with a sled like arrangement that slid on the
hair pin as a shorting bar and also had the link on it.
This tank circuit must have been 10 feet long. I don't have
room for something like that.
Guess I'll stick with plug in coils.
And again I'll ask if someone has a 1500T or 2000T EIMAC
transmitting triode. Please let me know. I felt lucky to
locate a 1000T last year.
73
Bill wa4lav
William L. Fuqua III P.E. E-mail WLFUQU00@POP.UKY.EDU Phone (606) 257-4155
Department of Physics and Astronomy CP-177 Chem. Phys. Bldg.
University of Kentucky , Lexington, Ky 40506-0055
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