Topband: best core material?

[Charlie Cunningham]

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 at contesting.com] On Behalf Of James
Rodenkirch
Sent: Monday, August 05, 2013 2:04 PM
To: BY THE LAKE; topband at 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 at isp.ca
> To: rodenkirch_llc at 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 at msn.com>
> To: <topband at 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
> >
> >
> > -----
> > No virus found in this message.
> > Checked by AVG - www.avg.com
> > Version: 2013.0.3392 / Virus Database: 3209/6552 - Release Date:
08/05/13
> > 
> 
> 
> 
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2013.0.3392 / Virus Database: 3209/6552 - Release Date: 08/05/13
> 
 		 	   		  
_________________
Topband Reflector