How about a gamma match?
Feedline is isolated from a 'physical connection' by the gamma
capacitor.
In the 'Mosley match' .. this is a similar situation .. the 'coax
without the braid' acts like a gamma capacitor of some sorts.
When Mosley came out with this .. I had my suspicions .. still do!
Don - N8DE
Gerald D'Entremont wrote:
>
> So...does it work? I went to look at a CL-205 this afternoon,
> which is the 5L 20M monobander that utilizes a similar (identical?)
> feed system. One half of the feed was missing...I'm presuming
> from your statement that one could fabricate a suitable replacement
> simply by stripping jacket and braid from some RG-8 and
> matching the opposing/remaining length? maybe I'm not willing to
> take enough on faith, but there seems something intuitively "wrong"
> with a 'matching system' where the feedline has NO physical connection
> to ANY part of the antenna!
>
> 73, Gerald W5BA w5ba@compuserve.com
>
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@contesting.com>
> Sent: Tuesday, March 26, 2002 6:46 PM
> Subject: Re: [Towertalk] Detuned Mosley CL-36-M
>
> >
> > On Tue, 26 Mar 2002 16:39:06 -0500 Pete Smith <n4zr@contesting.com>
> > writes:
> > > As I recall, it had an odd feed system that
> > > involved insulated wire inside the driven element,
> > > presumably providing some sort of capacitive coupling.
> >
> > That is the "MOSLEY MATCH"
> >
> > The DE is tuned to present an inductive reactance which is
> > canceled by the capacitance between the tubing and the
> > symmetrical lengths of RG8 with the outer jacket and braid removed.
> >
> > Tom N4KG
> >
> >
> >
> > ________________________________________________________________
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