Yes to both, Charlie - a friend of mine has a calculator to figure the exact
turns ratio BUT, at a web site I found for this antenna (used during an FO0
dxpedition) the ratio was defined as 8 turns in the primary, 28 turns in the
secondary (for 75 ohm cable so for 50 ohms it'll be something else but still
fairly close to your mentioned 4:1 ratio)
> From: charlie-cunningham@nc.rr.com
> To: rodenkirch_llc@msn.com; magoo@isp.ca; topband@contesting.com
> Date: Mon, 5 Aug 2013 14:24:05 -0400
> Subject: Re: Topband: best core material?
>
> BTW, Jim
>
> I assume that 18:1 is the impedance ratio, and the turns ratio is of the
> order of 4:1 or so
>
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of James
> Rodenkirch
> Sent: Monday, August 05, 2013 2:04 PM
> To: BY THE LAKE; topband@contesting.com
> Subject: Re: Topband: best core material?
>
> Sorry - didn't make it crystal clear that this is a Delta shaped variant of
> a EWE antenna!!!!
>
> My bad for not utilizing all of the necessary verbiage to make that
> clear....you see it in ON4UN's latest book on page 7-104.
>
>
>
>
> > From: magoo@isp.ca
> > To: rodenkirch_llc@msn.com
> > Subject: Re: Topband: best core material?
> > Date: Mon, 5 Aug 2013 14:00:48 -0400
> >
> > A full-wave delta loop would have the transformation done with a 1/4 wave
> > line of 75 ohm cable. This must be something other than a full-wave loop?
> >
> > Bill VE3NH
> > ----- Original Message -----
> > From: "James Rodenkirch" <rodenkirch_llc@msn.com>
> > To: <topband@contesting.com>
> > Sent: Monday, August 05, 2013 1:33 PM
> > Subject: Topband: best core material?
> >
> >
> > >
> > > I have a schematic for a delta shaped loop that shows I'll need an 18:1
> > > transformer to transform the 950 ohms of the antenna to 50 ohms (feeding
>
> > > it with 50 ohm coax).
> > >
> > > One transformer diagram shows an FT-140-43 core being used.
> > >
> > > BUT, looking over some of Tom's, W8JI, write-ups, I see where he uses 73
>
> > > material instead.
> > >
> > > I see where 77 material replaced 73 material so -- is an FT-140-77 the
> mo
> > > betta way to go?
> > >
> > >
> > > Thanks, in advance, for any advice/info. Jim Rodenkirch K9JWV
> > >
> > >
> > >
> > > _________________
> > > Topband Reflector
> > >
> > >
> > > -----
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> > > Version: 2013.0.3392 / Virus Database: 3209/6552 - Release Date:
> 08/05/13
> > >
> >
> >
> >
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>
> _________________
> Topband Reflector
>
> _________________
> Topband Reflector
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Topband Reflector
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