> Thanks for the info and suggestions, Herb. One additional question,
> however. Are you certain the 100 ohm impedance of the WD – 1 pertains
> to two parallel links of the wire, with 6 inch spacing? I know that
> open wire feeders with 6 inch spacing typically have about 600 ohms of
> impedance.
> 73,
> Jim W8ZiR
>
> Sent from my iPad
>
>> On Sep 20, 2014, at 8:34 AM, Herbert Schoenbohm
>> <herbert.schoenbohm@gmail.com> wrote:
>>
>> Jim, The DXE boxes are designed for 450 ohm ladder line which has a much
>> higher impedance than WD1-A wire. Using the DXE boxes may work but Gary's
>> boxes (KD9SV) will work better as they are designed for the 100 ohm
>> impedance of WD-1A. I also understand that DXE may now sell the boxes
>> designed for WD-1.
>>
>> Herb Schoenbohm, KV4FZ
>>> On 9/20/2014 10:06 AM, Jim Garland wrote:
>>> I want to replace the 450 ohm ladder line for my two DXE 720 ft long
>>> bi-directional beverages with two lengths of WD-1/TT field telephone wire.
>>> The wires will be secured only at the ends, but will be suported along their
>>> length by ceramic insulators mounted on 4x4 posts spaced every 60 ft. The
>>> spacing between the parallel wires will be about six inches. Here are my
>>> quesetions: First, does anybody know what the likely impedance is of this
>>> configuration, or if not, how to measure it? Second, if I keep the DxE
>>> matching trnsformers used with the 450 ohm ladder line, will beverage
>>> performance be degraded noticeably with the new wures if, say, the impedance
>>> of the new line turns out to be 600 ohms or so? In other words, as a
>>> practical matter how important to performance (e.g., F/B ratio and
>>> low-noise) is it to make sure impedances are matched.
>>>
>>>
>>> Finally, a mechanical question. I want to have a pulley at one end of the
>>> parallel wires to equalize the tension in the wires. I've not been able to
>>> find a good pulley with a five or six inch diameter, except for nylon
>>> pulleys used for clotheslines. Do you think one of these could be used.
>>> There will be no motion of the pulley, since it is only used to equalize
>>> tension. The field telephone wire is rated at 200 lbs maximum tension, and
>>> I'm guessing the actual tension will be about half that.
>>>
>>>
>>> Thanks!
>>>
>>> Jim W8ZR
>>>
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