Look at it closely. It is three wires (Radio Shack rotor wire) joined at
opposite ends to make one long wire. The 70 foot model actually has a "run"
of 210 feet - 105 feet on each side. Funny, Radio Shack rotor wire comes in
70 foot rolls.

Attach ladder line to a middle insulator. Add up the cost and you'll save a
lot by doing it yourself. I have seen a Cobra and it looks very well made
but I have never used one.

The principal is called linear loading, and it is a very effective way of
getting maximum benefit out of short antennas. It is far more efficient
than coils. ON4UN's book talks a lot about it but I couldn't find much
discussion on the effect of having the wires so close together. He does
advise, on page 8-13 of the Third Edition, "make sure the separation between
the element and the folded linear-loading device is large enough, and that
you use high-quality insulators to prevent arc-over and insulator damage."
He doesn't define "enough" and the phrasing of the sentence makes it sound
like the only concern with having them too close is arc-over. On the same
page, he warns modeling is "very tricky." From the discussion that follows
on this thread, I would say that is an understatement.
--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64


"Bert Craig" wrote in message
. net...
Opinions please. :-)

http://www.k1jek.com/

It got pretty rave reviews on eHam.

http://www.eham.net/reviews/detail/3...9a7885c56da2cc

--
Vy 73 de Bert
WA2SI
FISTS #9384
QRP ARCI #11782