>Why does it need to be? My Henry 3K Premier (3CX1200) wasn't "neutralized,"
>although it did suffer high failure rates of the doorknob caps in the plate
>tank (loading padders), not sure what all that was about.
Heath and Gonset Once had "neutralized" g-g amplifiers. Both had a well
deserved reputation for squirreliness. Gonset disappeared. Heath
apparently saw their error and never again designed a "neutralized" g-g
amplifier kit. Perhaps MFJ-Ameritron will someday wake uo?
>When those caps
>fail with a bang, they don't take the amplifier off the air,
The caps fail because, according to the cap mfg, they are designed for
RF-coupling and bypass service, not tuned circuits. Padder caps must be
temperature stable and able to handle the RF current present. Bypass
caps won't and don't. Amazingly, neither Dennis Had, nor Dick Ehrhorn
nor Henry Radio apparently bothered to Read the Jennings/ITT RF-cap
catalog. // Because temp-stable caps are not usually available in values
over 100pF, in commercial amplifiers, multiple temp-stable dorknob caps
are paralleled to do the job of tank C padding.
...
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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