I don't know what all this fuss is about. Sure plating has an effect on
UNLOADED Q. But, once it is loaded, the load resistance is the dominating
factor when it comes to Q of a HF amplifiers tank circuit. In fact modern
amplifiers use PI-L networks with relatively low Qs, around 10 or so, to
keep the circulating currents low so they don't have to use big expensive
band switches like in the B&W 850.
73
Bill wa4lav
At 07:59 AM 6/16/2005 -0500, Larry Carman wrote:
>I was told by a pro amp builder to leave out the silver and use copper only
>in the tank circuit. Reason: because it helps prevent parasitic on the
>higher frequencies. I'm speaking of HF amps working to 30 MHz. Any Merits to
>this???
>Larry N5BIP
>
>-----Original Message-----
>From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
>Behalf Of c-hawley@uiuc.edu
>Sent: Thursday, June 16, 2005 7:35 AM
>To: Harold B. Mandel; AMPS@contesting.com
>Subject: Re: [Amps] Alpha to Omega
>
>
>Keeps the silver from oxidizing. Silver is good...if it is
>thick enough. But, I doubt that the S meter on the other
>side of the world will notice the difference.
>Chuck, KE9UW
>
>---- Original message ----
> >Date: Thu, 16 Jun 2005 06:30:55 -0400
> >From: "Harold B. Mandel" <ka1xo@juno.com>
> >Subject: [Amps] Alpha to Omega
> >To: AMPS@contesting.com
> >
> >What good does gold plating do at HF frequencies?
> >
> >Matter-of-fact, what good does silver plating tank
>components
> >do at HF frequencies?
> >
> >I looked at the photo, in close-up, of the Omega.
> >
> >The air-variable capacitor stator support shaft
> >is bent, coming downwards in the middle of
> >the capacitor.
> >
> >The vertical RFC near the air-variable looks to have
> >a relay contact on its top. The relay looks like an
> >open-frame variety redolent of the Magnacraft
> >High Voltage tap-changer on the '77 series.
> >
> >Would not a Kilovac H-8, or similar, be more
> >apropos to a "state-of-the-art" design?
> >
> >I guess that when the white smoke escaped
> >during the hamfest the magic went with it.
> >Good choice of moniker: Omega....
> >
> >Hal Mandel
> >W4HBM
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