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When QST arrived in my mailbox last night I looked for the promised
article on teh "Miracle Whip", and there it was.

Far from being a joke the "Miracle Whip" (I think they may
run into trademark problems) antenna is one answer to the need for a
short, portable, easily ajustable antenna. It resembles in its design
the old Gotham verticals -- shortened. However, it's important to
remember that the Gotham verticals didn't work all that well.
Antennas have to play by the rules.

Rule 1: Make it big. Antennas marketed to the 817 user, are SMALL. If
they are small and convenient, they are guaranteed to work more
poorly than their big brothers.

Rule 2: Push as much current into the antenna as possible. A base
loaded antenna has zero current at its tip and maximum at its bottom.
It has the EFFECTIVE area of a whip half its actual height carrying a
uniform current. Center or top loading is for this reason preferable.

Rule 3: Get it in the clear. This antenna, and other small ones
designed to attach to an 817, are often used close to the radio
chassis or even to the body of a user. This proximity diverts energy
that would otherwise be avaiable for radiation. For best results, none
of our portable antennas should be run parallel to a nearby grounded
surface, which includes our own bodies.

Rule 4: Reduce losses. The ARRL Antenna Book, among others, explains
rather well how to reduce loading coil losses. That doesn't mean
manuifacturers do so. That old antenna-shoot-out winner, the Texas Bug
Catcher, with well spaced turns and minimum wire length for inductance
privided, is a pretty good coil. More compact resonators with
close-wound turns have more wire (more loss) per microhenry, and add
capacitance between turns as well, giving a weaker radiated signal.
Comparing 40-meter coils, a bug-catcher is about 6 inches long by 4
inches wide, space-wound with number 16 wire, a Hustler coil is about
6 inches long by two inches wide, close wound with about number 20
wire, and a coil from one of the imported multiband mag-mounts is
about an inch in diameter and four inches long -- I won't try to guess
what the wire size is!

4a: This includes GROUND losses. If you can't have a field of radials
or a swamp as ground, then (for better results) a resonated or tuned
counterpoise of least two wires, elevated, is needed. Even a mobile,
with a car as counterpoise, may have ten ohms of ground loss at 80
meters. That eats up a LOT of power, since the radiation resistance of
a typical 8 foot mobile antenna is on the order of ONE ohm - and these
tiny antennas, much less.

Mini-antennas suffer from all the deficiencies a QRP station should
try to avoid. W3FF cut right to the chase with his dipole. It is as
large and far away from ground loss as he can get it, does not need a
ground to work, and uses as little loading as possible. It is also a
pain to get between the trees while hiking (grin) and isn't quite
small enough for airline carry-on. Not that they want folks geting on
with PVC tubes that look like rocket launchers.

It is also true that when a band is REALLY open, anything works. Even
a light-bulb (see
). So I
don't write off the Maldol, or the Miracle Whip. [Heck, I LIKE
mayonaisse!] And in fact I've worked Japan, Fiji and Pensylvania using
a Radio Shack CB antenna just 22 inches long on the back of my 817.
It's just that I knew in advance what I was working AGAINST.

Those of us who buy one of the new, tiny antenna's without such
foreknowledge are going to be disappointed when the bands are only
"normal." And then we'll see a lot of 817's on E-bay. This doesn't
have to happen, if we all remember what we are buying. W6XR's antenna
talk graphs enjoyment against antenna size: When we go QRP we need to
pay even more attention to the antenna.

CU on the Short Waves!

Cortland

Nicely written up!

Thanks

Pres Waterman W2PW
c/o Patchogue Motors, Inc.
Long Island Ford and Kia dealer

GO BILLS!