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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