EMRFD Message Archive 1583
Message Date From Subject 1583 2008-04-22 19:49:31 VE4KEH Wire-Wrap Wire and Toroids (was help my junk box) I recall reading somewhere (though I can't remember where) that two
pieces of 30 gauge wire-wrap wire twisted 6 to 8 turns per inch had a
characteristic impedance of around 50 ohms. I don't know if it comes in
different insulating materials (I think the stuff I have uses "kynar",
if my memory & spelling is correct), but that may influence the
impedance a bit.
I imagine some 50 ohm wire-wrap transmission line and a small toroid
would make an excellent QRP choke balun.
More information on using twisted wire as transmission lines can be
found in an article called Twisted Magnet Wire Transmission Line by
Peter Lefferson. It's from an IEEE publication, but I found my copy
somewhere on the Web.