Esteemed Reflectees:
Re the comments by W0UN:
>Tree, interesting to see your use of the loop antenna on 80 and
>proposed use on 160. The antenna as described in the Ant. Comp.
>#2 is misnamed as a magnetic loop but it does work well.
I take some blame for this, as I have been feeding Tree this info
over the past few days. The name "Magnetic-U" I took from K5RP's original
article in Communications Quarterly (?); though later work questions the
"magnetic" moniker, that is still what many call it. I built 2, 1 each for
40 and 17m and had absolutely fabulous results here in New Mexico, The
Original Black Hole, with our rotten ground conditions.
>Extensive modeling by K9AN and myself plus testing on 40M by
>K9AN indicate that there is no advantage to making it into
>a 2-turn beast. A plain "squashed" quad loop will do the same thing.
John, what impedances do you see for a squashed, single-turn loop
of what H/V side ratios? W6SAI's old radio handbook shows a loop with a 2:1
side ratio has approx 40 Ohms Zo. Starting from there, the more you squash
it, the more it looks like a folded dipole with Zo nearing 280 Ohms.I
always preferred higher radiation-resistance antennas over our ground, and
K5RP's 115+j0 for a 2-turn, 30-degree vertical loop is nearly right on the
money. Besides, I HAVE to use low profile antennas here.
BTW, NM is indeed the Original Black Hole for RF. Beware of cheap
imitations. In fact, the more closely guarded data on this also supports
evidence of the Black Hole effect on other objects. Why do you think the
UFOs crash here instead of, say, Boring, Oregon or La Salle Colorado? Damn
things keep knocking over my 160m 4-square! This is the real reason I can't
compete on topband. Thus the need to use the lower profile Mag-U. And if
you dont believe this, there are rumors pervading smokey back rooms that
the Very Large Array (you DID see "Contact", didn't you?) is really a giant
tractor beam, but they haven't gotten all the bugs worked out yet; those
UFO's really get tangled up in my 4-square guywires when trying to escape.
This has been well covered up, of course. And this doesnt just
happen to me. Why do you think, with such a high ham-per-capita ratio as NM
has, we are so hard to find on the air? And this isn't the only conspiracy
to keep NM at a disadvantage; John has cornered the market on 65' poles,
and has the darn things just laying around in his junk pile, for goodness
sake!
See you on 160. "160, The Band!" That is, provided I can get all
the wires to stay fixed at the same time.
Sorry, I couldn't wait for April 1 to break this news....
73 de Jim, KF7E
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