*** As I understand it, the RCA g-g neutralizing circuit reduced
feedback at the operating frequency. The problem was/is that an 811A in
g-g configuration is unconditionally stable at HF. The sticky wicket is
that the HF neutralizing circuit provides a semi in-phase feedback path
at VHF at the same time it provides an out-of phase feedback path at HF.
Needless to say, in-phase feedback is essential for oscillation. //
Perhaps the problem was that the RCA engineer who came up with this
ill-reasoned circuit did not realize that schematic diagrams do not show
all of the tuned circuits that the amplifier builder must deal with.
Of these, the natural VHF resonance in the anode circuit seems to be the
most problematic.
>What was the purpose of the HA-10 Warrior
>"Neutralizing Capacitor"? Following the advice of
>many people I am going to remove it from my Warrior.
>73,
>Bill
>
>=====
>Bill Smith KO4NR
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