One mistake many make is placing the tube and even the plate choke near a
cabinet wall or even in a corner and now we have a nice new capacitor to
contend with. The Henry 8K is an example of a 3x3 amp with a history of
problems and sudden tube failures.
Others keep the side walls well spaced and then have a top cover only an
inch away. There seems to be an obsession with compactness and trying to
make a 5KW amp the same volume as a much smaller version.
Carl
KM1H
----- Original Message -----
From: "Dave White" <mausoptik@btinternet.com>
To: "Mike Saculla" <fqm@msn.com>; "amps@contesting" <amps@contesting.com>
Sent: Friday, July 16, 2010 3:29 AM
Subject: Re: [Amps] Size of Parasitic Chokes
> My current 3CX3000 amp has no parasitic suppressor at all. I originally
> built one using a coil and a large 50 ohm carbon resistor but found low
> efficiency.
>
> I spoke to Reid Brandon W6MTF at Eimac and he advised me to simply take it
> out and not wory about parasitic suppression.
>
> I have had no problems whatsoever. However I was totally neurotic about
> isolating the plate compartment from the cathode area. Everything is
> either screened or runs via feedthru capacitors and the base and top
> panels are rf-sealed with finger stock.
>
> The tubes I got (Dayton fleamarket if I recall correctly) were 3CX3000F7s
> though I removed the filament leads with a blowtorch (carefully!) so
> they'd fit an RF Parts coaxial socket. The grid is earther directly to
> the chassis via a finger stock grid ring.
>
> Hope this helps
> Dave G0OIL
>
> -----Original Message-----
> From: "Mike Saculla" <fqm@msn.com>
> To: "amps@contesting" <amps@contesting.com>
> Sent: 16/07/2010 05:07
> Subject: Re: [Amps] Size of Parasitic Chokes
>
>
> I see 3CX3000A7 amps with no suppressor at all. How stable have any of you
> found this tube to be? Anyone have one take off on them with no
> suppressor? Or should I include one just to be safe?
>
> Mike K6MDS
>
>
> --Forwarded Message Attachment--
> From: km1h@jeremy.mv.com
> To: sub1@rogerhalstead.com; Amps@contesting.com
> Date: Thu, 15 Jul 2010 20:53:59 -0400
> Subject: Re: [Amps] Size of Parasitic Chokes
>
> The YC-156 doesnt use a socket and hasnt shown any need for a suppressor.
>
> [truncated by sender]
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