Topband: WD1A

[kd9sv]

Mike, the measurements I took here on a short (300ft) WD-1A with average
height of 5ft using the method W8JI recommends with a termination resistor
(pot) and MFJ-259 showed an impedance of 140 ohms on both 160 and 80 meters.
I did not attempt to measure at higher freq's...de gary, kd9sv

-----Original Message-----
From: topband-bounces at contesting.com [mailto:topband-bounces at contesting.com]
On Behalf Of Mike Waters
Sent: Monday, July 23, 2012 10:13 AM
To: topband
Subject: Re: Topband: WD1A

I think the characteristics of so-called WD-1 surplus phone line varies.
FWIW, the two short samples of WD-1 that I have here are as follows:

115 ohms impedance, calculated from the following: .033 diameter
(averaged), .0685 spacing. The dielectric constant of the insulation
(polyethylene) is 2.2.

I just made three transformers for someone using that line as a
bi-directional Beverage, but I think more tests need to be run to see how
it really works in actual practice. But so far, so good. :-)

73, Mike
www.w0btu.com

On Mon, Jul 23, 2012 at 8:43 AM, Tom W8JI <w8ji at w8ji.com> wrote:

> Has anyone ever made any attempt to characterize the line at HF?
>
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