John,

A single wire is going to have a huge variation in impedance over the 5 - 30
MJz range. You are much better of with a fan type antenna that has multiple
dipoles, all tied together at the feedpoint. I saw one of these in a ham
catalog, but can't remeber where. For a compromise, I would cut dipoles for
6.5, 11, and 16 MHz. Tie them together at the feedpoint, and fan out the
ends. You don't really need a balun, but if you want to, use a 1:1 with
either 50 or 75 Ohm coax. The length of eacch dipole in feet is 468/MHz,
half of that length on each side.

Tam/WB2TT
"Jon Gauthier" wrote in message
...
I have a Grundig YachtBoy SW/MW receiver that I'd like to connect to an
external long-wire antenna, but I'd like to have the antenna on the
roof, while I'd be listening in my office in the basement. I'd like to
make a couple of simple baluns to match it to 75 ohm coax. What's the
impedance that the receiver is expecting? It's just a phono plug
input... Grundig's web site is, ah, not very technical...

--
Jon Gauthier

Given the likely reaction to an increase in
terror-alert level to "severe threat imminent,"
wouldn't a more appropriate alert color be brown?
-Brad Simanek on www.ruminate.com