The grid is already (dynamically) grounded by capacitors, expecially on
higher frequencies. A mechanichal grounding is practically ininfluent
and produces only marginal changes/improvements.
In SB220 modified for 160m the original grid-ground capacitance is
instead not enough and straps fix the gap. (doubling capacitance
produces the same effect).
L is basically uneffective (dynamically) but often works as a grid
fuse. (Expecially in case of sudden antenna faults)
Same considerations largely apply to TL 922.
73,
Mauri I4JMY
> ---------- Initial message -----------
>
> From : owner-amps@contesting.com
> To : A P <apight@pa.net>
> Cc : amps@contesting.com
> Date : Tue, 26 Sep 2000 17:19:44 -0500
> Subject : Re: [AMPS] SB-220 Smoke Test
>
>
> So what benefit did directly grounding the grids bring?
>
> More output on any or all bands for the same drive power?
>
> The same output on any or all bands for LESS drive power?
>
> A better VSWR between the radio and the amplifier input? The stock
220 input
> VSWR on 10 and 15 is pretty poor.
>
> Does the amp tune smother on 10 and 15?
>
> In short, you said it works, but what does the change do to make it
worth while?
>
> 73,
> Tim K3LR
>
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