With some quick calculations and a check of a chart of wire gauge and
resistance, that 25 ohms for 400m is about 19 ohms/kft which works out to
something between 22 and 23 gauge copper wire. I don't have exact specs for
WD1A handy, but I think it's probably close to something in the 22-24 gauge
range since it's a mix of copper and steel strands but is physically close to
about a 22-20 gauge wire.
The resistance you're seeing seems about right to me. Note that many
multimeters aren't very accurate in the low-ohms range (you really need a
4-wire ohmmeter for that), so you're resistance will vary a bit from what any
charts of wire resistances tell you.
-Bill
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of
> Martin
> Sent: Wednesday, December 03, 2014 8:25 AM
> To: topband@contesting.com
> Subject: Topband: Restistance of wire
>
> Topbanders,
> i have a spool of twisted wire for military field telephone use, similar to
> WD1-
> A . It has some strands of copper and some strands of steel.
> I built the reflection transformer and installed both the transformer and the
> wire . The length of the beverage is about 200m. To my surprise i measure
> about 25Ohms with a Multimeter at the feed end of the beverage.
> So there is 200m one way, the transformer, and 200m back = 400m of wire.
> I believe 25 Ohms is way to high for 400m?
>
> Any advise welcome.
>
>
>
> --
>
> Ohne CW ist es nur CB..
>
> 73, Martin DM4iM
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