Denton, I've tried that before too. It is a nightmare to do.
Believe me, building your own openwire feedline is about 10x faster and
easier if you use the right spreaders.
It took me about one hour to build my feedline in OKC. It was about 50 ft.
long.
Tie the two wires to the fence about 2" apart (or whatever the width of the
spreader is), extend them in parallel across the yard, tie the other ends
each to a strong bungee cord and continue with rope to a convenient point to
fasten the end. The bungee keeps the lines tensioned. Then just walk along
the wires, snapping the spreaders into place. I used a 1 ft. ruler and
placed one spreader each foot.
It's a piece of cake to build, but it's not cheap. Quality has it price, as
always.
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of denton
sprague
Sent: Monday, July 29, 2013 7:56 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] TT 238C will not tune
too bad they didn't test the 450 ohm feeders.with most of the webbing cut
out of the middle. That is what I did, and I don't get much change from wet
to dry weather.
On Jul 29, 2013, at 2:31 AM, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
> Steve,
>
> Indeed that paper contradicts the ARRL results and supports the 3dB claim.
> In fact it shows closer to 5 dB.
>
> Joel responded to the criticism on his results but that was about 4
> years ago and I can't recall what he said.
>
> In view of that, then true openwire is the way to go outside of the shack.
> Inside the shack it is more convenient to run the window line.
>
> Thanks for the link. Hadn't seen that one before and based my opinion
> solely on the ARRL results.
>
> 73
> Rick, DJ0IP
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Steve
> Hunt
> Sent: Monday, July 29, 2013 11:06 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] TT 238C will not tune
>
> A number of points:
>
> 1) An "ugly" balun is a poor choice for use at the output of a
> wide-band tuner. It has high choking impedance over only a very narrow
> band of frequencies, and outside that narrow band the impedance is
> almost totally reactive; in some situations that means it can actually
> increase the CM current.
>
> 2) My 238 manual has a totally ambiguous statement about stringing the
> dial pointer. To start the process it says: "Run the inductor to the
> full clockwise stop (roller to the rear)". Actually, full clockwise
> has the roller to the front!!! Depending on whether you chose to go
> with "full clockwise" or "roller to the rear", you could end up with
> the pointer showing maximum inductance at zero or at 30.
>
> 3) The high attenuation figures for wet ladderline derive from the
> experimental work of Wes Stewart N7WS:
> http://users.triconet.org/wesandlinda/ladder_line.pdf
> The later experimental work by ARRL showed lower attenuation for wet
> ladderline, but the experimental method was soundly criticised.
>
> Steve G3TXQ
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