> ---------- Initial message -----------
>
> From : "Jeff Wolf" <da_kang@hotmail.com>
> To : i4jmy@iol.it, guyr@n-link.com, amps@contesting.com
> Cc :
> Date : Fri, 03 Nov 2000 14:28:33 GMT
> Subject : Re: [AMPS] RF Choke
>
> Mauri,
>
> It sure does enhance the gain at HF!
>
> You saying that floating the grid above AC ground doesn't decrease
gain in
> the HF spectrum?
Not only a 1mH choke is existing but also capacitors.
If the choke is not open and capacitors not broken, the circuit
reactance is neglegible and SB220 gain is totally unaffected.
Some difference is appreciable if SB220 is converted for 160m, in that
band.
>
> If your statement is correct, my SB220 must be failed, because drive
power
> dropped 10 to 15 percent with directly grounded grids Vs. stock
SB220.
My SB220 gain didn't change at all between 80 to 10 when tried a low
inductance joint to connect grids directly to ground. Other people who
did the same mod. obtained no measurable gain improvements.
I think what happened to you was probably caused by defective
capacitors.
73,
Mauri I4JMY
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