Below is an e-mail I received this A. M from Rex, K0KP.
congrats, Rex
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Hello Richard,
Thanks for your website. I refer to it often. Also thanks for the low Q
parasitic suppressors, my amplifier has been unconditionally stable since
I installed them some years ago. I am a believer.
Under your website article League Fatigue; I note with interest your
comment that Eimac recommends a Q of 5, not a Q of 2, for the tuned input
of a G-G amplifier. Not according to the Eimac literature I have in my
hand at this very moment. Eimac circular 3928 (Revised 8-5-80) (c)
1968, 1970, 1973, 1977, 1979, 1980 by Varian. This is the Technical Data
sheet for the 3-500Z High-Mu Power Triode. Page 4 states as follows:
"INPUT CIRCUIT - When the 3-500Z is operated as a grounded-grid rf
amplifier, the use of a resonant tank in the cathode circuit is
recommended in order to obtain greatest linearity and power output. For
best results with a single-ended amplifier it is suggested that the
cathode tank operate at a Q of two or more."
It appears that your original article was correct after all.
73 - Rex Greenwell, K0KP at Fish Lake, 20 KM NW of Duluth, MN
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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