Tom...and others,
OK...I believe! Yes, I'm familiar with both the Cushcraft and Wilson.
It's just that the coupling of a short piece of RG8 center conductor
flopping around inside an 1 1/4" section of tubing seems like awfully
'loose' coupling to me. I DID note that the DE length dimensions
in the documentation were LONGER than that of the reflector, which
would support the greater inductive reactance as per the original post.
Thanks for all the replies and clarification.
73, Gerald W5BA w5ba@compuserve.com
----- Original Message -----
From: <n4kg@juno.com>
To: <TOWERTALK@contesting.com>
Sent: Wednesday, March 27, 2002 6:05 AM
Subject: Re: [Towertalk] Detuned Mosley CL-36-M
>
> The MOSLEY MATCH is a CAPACITIVELY coupled match.
>
> So is the GAMMA MATCH.
>
> Cushcraft and Wilson BOTH produced antennas with
> Gamma Matches utilizing RG8 center conductor and
> insulation inserted inside (3/8 ? inch OD) tubing as
> the Gamma Capacitor. Remember the 4 element
> Skywalker series of monoband Yagi's from CC?
>
> Neither has a DIRECT connection to the DE.
> SO WHAT? That's how CAPACITORS work.
> What's all this skeptimism about?
>
> Tom N4KG
>
> On Tue, 26 Mar 2002 20:06:15 -0600 "Gerald D'Entremont"
> <w5ba@compuserve.com> writes:
> > 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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