> There was a valid reason for that in the 30's, tubes had long internal
> connections and shielding was poor. Components were poor
> quality, frequency performance was limited by stray reactances in
> the system. Amplifiers built with 1930's technology and
> components tended to oscillate at or near the operating frequency,
Could it be that "self-oscillation" at or near the operating frequency and
VHF oscillation (parasitics) are rooted in the same mechanical design and
layout limitations, and depending on the accuracy of the physical design,
oscillations may occur 1) at or near the operating frequency, 2) at VHF
frequencies if ample gain exists, or 3) no oscillations at all if the design
and layout is nearly perfect? If so, can't we simply view the suppressor as
a device to temper slight layout flaws, slight inconsistencies between
amplifier wiring and mechanical geometries from one production unit to the
next, and slight inconsistencies in tube manufacturers and processes?
> You see tubes like the 8877 or 3CX800, or 3CX1200Z7 often don't
> require any suppression at all....or at the best minimum
> suppression.
Not on the amps I see. I see some form of suppressor on all the 8877 and
3CX800-based HF amps in current production. Is anyone presently producing
an amp utilizing the 3CX1200Z7?
-Paul
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