I've been using a single Valor 160 whip triple mag-mounted on a 24x56 foot
metal roof, with decent results, for a couple of years now. 'define decent' ? I
can hear out to about 1000 miles, and if I can hear a station clearly, I can
usually get a reply. Noise level here is high, and if it wasn't for the DSP
Noise Reduction feature in my IC-746Pro, the band wouldn't be useable.
As for the mobile-whip dipole idea, I have a pair of 40m Hamstick mobile whips
as a dipole about 6 feet above the roof on a mast, and sometimes they give a
noticeably better signal than a triple resonator (80-40-30m) mobile whip
oriented vertically on the same roof. I've toyed with the idea of a 160m dipole
with the Valor whips, but they are MUCH heavier than the hamsticks for 40, and
I'd definitely want to have some sort of support line from higher up on the
mast to the end of the loading coils. We get some really stiff 'Santa Ana'
winds out here. I might even go with a separate, sturdier mast. (the 40m dipole
is on a lightweight mast with a VHF Discone at the top). (If you haven't had
your hands on a Valor 160 whip - if somebody assaulted you with a 40 hamstick
wipe, you'd be irritated. If somebody hit you with a Valor 160 base and loading
coil, you'd be seriously injured!)
As for the idea of using a coupole of sets of mobile whip dipoles as a beam on
160m - getting decent element spacing would be quite a trip! You shorten the
elements by using the whips, but element spacing would be a huge challenge -
maybe a phasing network of some sort would work. Those of you who use the
modeling programs might want to play with that one!
Fred Wagner, KQ6Q
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