Okay. Yes, at the rig end of the feedline, 1:1. 73 - Rich, KE3Q
----- Original Message -----
From: "Don Havlicek" <n8de@thepoint.net>
To: "RICHARD BOYD" <ke3q@msn.com>
Cc: <N4CW@aol.com>; <towertalk@contesting.com>
Sent: Thursday, September 30, 2004 11:37 AM
Subject: Re: Telrex TB5EM hairpin
> "It worked great, 1:1 SWR...."
> Where was this fantastic SWR measured? .. at the antenna? .. or at the
> far end of the feedline? I'll bet that it's the latter case.
> The balun and hairpin are designed to obtain the best SWR on this
> tri-band antenna while eliminating [to the best extent] the currents on
> the coax shield ...
> For Field Day .. anything that 'seems' to work ...WORKS! [been there ...
> done that!
> Put the balun and hairpin back on and I'm sure you'll find the antenna
> actually does what it is DESIGNED TO DO.
> Don
> N8DE
>
> RICHARD BOYD wrote:
> > Let me ask you TB5EM guys a question.
> >
> > I have had one for years and use it every year for Field Day on our RTTY
> > station. We pressed it into service when someone said, "Anyone have a
> > tribander we can use?" and I had it here in storage. Quickie-style, we
> > just
> > attached center conductor and braid, each, to each side of the split
> > driven
> > element with stainless steel hose clamps, didn't use the stainless steel
> > screws that go through the tubular Cycolac (or whatever it is) insulator
> > at
> > the center. It worked great, 1:1 SWR, the appropriate SWR curve, good
> > gain
> > and directionality. We have never seen any reason to change it. I've
> > put
> > it up on a portable tower at home and have been using it and it's been
> > very
> > effective here too. I came across a second TB5EM and plan to feed it
> > the
> > same way and have them up in a stack.
> >
> > So, getting to the question: What degradation in performance should I
> > be
> > expecting to see by virtue of not having the balun or hairpin?
> >
> > 73 - Rich, KE3Q
> >
> >
> > ----- Original Message -----
> > From: "Don Havlicek" <n8de@thepoint.net>
> > To: <N4CW@aol.com>
> > Cc: <towertalk@contesting.com>
> > Sent: Thursday, September 30, 2004 10:32 AM
> > Subject: Re: [TowerTalk] hairpin
> >
> >
> >
> >>Just measured mine.
> >>
> >>The 'loop' is 25.5 inches either side of the boom attachment point, thus
> >>is 51 inches overall.
> >>
> >>The shape is almost a continuous curve from driven element attachment
> >>point to boom attachment point EXCEPT the first 3 inches [nearest the
> >>driven element] at quite 'straight' with a bend at the 3 inch point.
> >>
> >>Don
> >>N8DE
> >>
> >>N4CW@aol.com wrote:
> >>
> >>>No dimensions are given in the "Assembly Instructions" sheet that I
> >>>have.
> >>>Direct measurements will have to be made.
> >>>Telrex wasn't long on details...,"If you have followed simplified
> >>>assembly
> >>>sheet carefully, you are ready to connect your 52 Ohm co-axial to the
> >>>'Balun'
> >>>provided. Mount the antenna in the clear, 34 fet or higher." Also, "Do
> >>>not
> >>>force, alter, modify, or try any inventions! Telrex has precision-tuned
> >>>and matched
> >>>this antenna to provide optimum 10, 15, and 20 meter gain, F/B ratio,
> >>>and
> >>>'balanced-pattern'."
> >>>No dimensions, other than hardware sizes, are given.
> >>>73,
> >>>Bert, N4CW/1
> >>>_______________________________________________
> >>>
> >>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> >>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> >>>any questions and ask for Sherman, W2FLA.
> >>>
> >>>_______________________________________________
> >>>TowerTalk mailing list
> >>>TowerTalk@contesting.com
> >>>http://lists.contesting.com/mailman/listinfo/towertalk
> >>>
> >>
> >>
> >>_______________________________________________
> >>
> >>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> >>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> >>any questions and ask for Sherman, W2FLA.
> >>
> >>_______________________________________________
> >>TowerTalk mailing list
> >>TowerTalk@contesting.com
> >>http://lists.contesting.com/mailman/listinfo/towertalk
> >>
> >
> >
>
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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