*Don’t* use the two conductors of a single run of twisted pair WD-1A as the
transmission line - you’ll get a *lot* of loss in the transmission line.
Instead parallel the two wires and run two lengths WD-1A (as Jim Garland says).
2 inches / 50mm spacing between them will give a line impedance of around 450
ohms, and much less loss.
Jeremy G3XDK / G4AQG
> On 12 Jan 2020, at 23:24, Herbert Schoenbohm <herbert.schoenbohm@gmail.com>
> wrote:
>
> Probably the most durable two conductor is Military WD-1A telephone cable.
> available on eBay for $50 for about a half-mile. Special lower
> impedance transformers are required to match the line's impedance. It is
> also a great source for very durable single wire Beverages with both ends
> connected together.
>
> Herb, KV4FZ
>
> On Sun, Jan 12, 2020 at 11:26 AM John Kaufmann via Topband <
> topband@contesting.com> wrote:
>
>> I'm looking for a source for durable ladder line for making two-wire
>> reversible Beverages for use at the KC1XX contest station. In the past
>> we've used the line sold by DX Engineering but over the years we've found
>> that the plastic spacers between the wires become brittle and break off.
>> It
>> may be UV exposure that causes this. We also get some pretty severe
>> weather
>> at KC1XX hilltop location, with ice in the winter and frequent strong
>> winds.
>> The spacer breakage sometimes exposes the wires, which then become twisted,
>> and the ladder line generally becomes weakened and prone to wire breakage.
>>
>>
>>
>> What else is available commercially?
>>
>>
>>
>> 73, John W1FV
>>
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>>
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Jeremy Maris
140 Edward Street, Brighton BN2 0JL
jeremy@maris.plus.com
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