These baluns do work well.
I use them on all my beams and tribanders. However, I use teflon coax which
eliminates the need to seal anything.
James Wolf, KR9U
> Thanks for the corrections Arne!
>
> Bill
>
> On 160-40M the number of turns for both the coax and the wire
> should be 5 NOT 7. The nominal dia is about 6.5 inches.
> George used #10 or #12 wire NOT #16 in his article in news
> letter I have. This is from a NCDXC news letter article
> published after the February/March 1980 articles in Ham Radio
> magazine.
>
> The version for 10-20M uses 2.5 turns each (wire and coax).
> Use these and they work. Be sure to seal well all open ends
> and around where insulation was removed (I used RTV and
> electrical tape and more RTV). Wrapped entire loop with
> electrical tape.
>
> 73 de Arne N7KA
>
> ----- Original Message -----
> From: "Bill Tippett" <btippett@alum.mit.edu>
> To: <topband@contesting.com>
> Sent: Tuesday, December 23, 2003 6:50 PM
> Subject: Re: Topband: 160 Meter BALUNS
>
>
> > Here's a simple balun that works well on 80/160
> > which requires only 100 inches of RG-8X coax. I used it
> > for many years in Colorado running 1.5 kW to a trapped
> > dipole for 80/160 with no problems. The original design
> > came from a Ham Radio series but I don't have the
> > exact reference. I recall the designer had made
> > measurements using an HP Network Analyzer and
> > the balance performance was excellent on 80/160
> > compared to commercial baluns.
> >
> > 1. Carefully remove a small ring of the coax cover at
> > ~100" from the end.
> >
> > 2. Solder ~100" of wire around the braid at this point.
> > I recall I used #16 insulated wire.
> >
> > 3. Loosely wind 7 turns of the coax in one direction
> > (about a 6 or 7" diameter coil) and loosely wind 7
> > turns of the wire in the OPPOSITE direction.
> >
> > 4. Solder the wire to the inner conductor at the end
> > of the coax (after separating 2-3" of braid as a pigtail).
> >
> > 5. Waterproof the coax ends and the area where the
> > wire was attached.
> >
> > 6. Secure the loosely bundled coil of coax and wire
> > with tape or tie-wraps.
> >
> > 7. Attach the coax shield to one side of the antenna
> > and the center conductor (including attached wire)
> > to the other side.
> >
> > Instead of using 50' of coax, this uses only
> > a bit over 8' and works well. Maybe someone has
> > the exact Ham Radio reference but I'm fairly certain
> > my memory of the construction is correct. If I made
> > a mistake, hopefully someone will correct it.
> >
> > 73 & Merry Christmas!
> >
> > Bill W4ZV
> >
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> > Topband@contesting.com
> > http://lists.contesting.com/mailman/listinfo/topband
>
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