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[AMPS] SB-220 Smoke Test

To: <amps@contesting.com>
Subject: [AMPS] SB-220 Smoke Test
From: i4jmy@iol.it (i4jmy@iol.it)
Date: Wed, 27 Sep 2000 09:18:00 +0200
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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