Thanks, Carl. I might do that.
Something like this ought to work using your method:
http://www.ebay.com/itm/Capacitor-air-variable-capacitor-tuner-dual-30-Pf-capacitor-/151482230814
The neut cap that Paul has is a common disc type, which I think would arc
at the capacitance required (my guesstimate is about 15 pf max since the
G-P is 6.3 pF per tube). I suppose it would be OK if I put some thin Teflon
between the discs.
And I love the idea of starting out cold with a small LV variable! I have
plenty of those.
73, Mike
www.w0btu.com
On Mon, Jan 26, 2015 at 5:19 PM, Carl <km1h@jeremy.qozzy.com> wrote:
> You can always use a piece of regular solid dielectric coax or even
> hardline off the anode and then followed by a LV variable. I used a piece
> of RG-17 and a small mil surplus cap with about 1500-2000V spacing ages ago
> off a pair of 6500V swamped grid 4-1000A's. Worked just fine at 10M.
> Supposedly that amp is still in service out in Ohio.
>
> Cold neutralize with a mica trimmer or small variable cap, measure, and
> then compute what you need to build with sufficient tuning wiggle room.
> Always neutralize on the highest band you are using.
>
> Carl
> KM1H
>
> --------------------------------------------------
> From: "Mike Waters" <mikewate@gmail.com>
> Sent: Monday, January 26, 2015 5:47 PM
> To: <amps@contesting.com>
> Subject: Re: [Amps] 833A GG
>
> Anybody know where I can get a neutralizing capacitor for two paralleled
>> 833Cs?
>>
>> What I had in mind is in the second photo from the top at
>> www.criticalradio.com/833%20Rig%20Project/Web%20Pages/
>> RF%20Deck%20Pictures.htm
>>
>> ... the 3-plate variable on the right. I've seen something similar in
>> commercial paralleled 833A RF decks; those looked like they had die-cast
>> zinc plates.
>>
>
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