[TowerTalk] antenna feed line (kind of on topic)

[Jim Lux]

Probably really dependent on the insulation and such things as how tightly
twisted it is. AWG10 is almost always stranded, which makes figuring out the
conductor diameter a bit tricky (since AWG is the copper area, not the
overall diameter, and the latter is what counts for impedance).

Most twisted pair wire seems to come up around 100 ohms, give or take, but
that's probably an artifact of how much insulation thickness there is on a
given diameter conductor.

As far as feed line.. you could always twist up a batch, measure it, and use
it.  Twisted pair is used at 100 MHz plus frequencies (if not GHz)  to good
effect.  Certainly, the folks wiring UTP networks worry about the same kinds
of things that radio people do: loss, crosstalk, mismatch, etc.  The tool of
choice is a TDR to look for miswiring and bad installations.


----- Original Message -----
From: "mike l dormann" <w7dra at juno.com>
To: <towertalk at contesting.com>
Sent: Tuesday, April 26, 2005 7:59 PM
Subject: [TowerTalk] antenna feed line (kind of on topic)


> anyone here ever use #10 house wire (singe insulated strand, the kind
> that goes inside armored cable) as twisted pair?
>
> seems like it would be in the high 90s impedance, and easier for me to
> get than KW  75 ohm twinlead (to feed my delta loop with balanced line)
>
> thanks  mike w7dra
> _______________________________________________
>
> See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk