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Old September 13th 05, 05:18 PM
 
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Phil found a simple dipole only a few feet above ground would
outperform
a mobile whip on 40 or 75 meters.

NVIS sure...Wouldn't be so sure about long haul... My 40 meter
mobile beats my home dipole at 40 ft on a 1000 mile path.

Here is Phil`s Table 3:

Hustler 75-meter Mobile whip mounted vertically on top rear corner of
trailer-------S7

Part of the problem...His mobile is stunted...

Same as above with 60-foot counterpoise connected to
trailer-----------------------------S9

Two Hustler mobile whips back to nack
as a horizontal loaded dipole-------------S9+5dB

Again kinda stunted due to the lousy hustler coils...
Could be better than that if better coils were used.

60-foot horizontal wire 8 feet high using trailer (30-ft.
Airstream)
as ground------S9+10dB

Pretty mediocre if NVIS...

Hustler 4BTV trap vertical with
75 meter resonator-------------------------S9+10dB
120 foot dipole, 15 feet high at
center------------------------------------------S9+20dB

Airstream Loop antenna------------------S9+20dB

Home station dipole 50 feet high------S9+30dB

Sounds like these are all NVIS paths... For those,
I agree, a dipole/loop is usually best. One problem though...
Often when mounting a low dipole next to a large metal trailer, etc,
the coupling often will make tuning quite difficult. I'd try to get
the dipole as far away from the trailer as possible *if* it
acts squirrely... But a *good* mobile antenna could often
be quite good to longer hauls. On the higher bands, a good
mobile antenna should be just fine.
If it were me, I'd #1 run the best mobile antenna I could rig up
as a vertical. Then I'd run a dipole for low band NVIS stuff. In my
case, I prefer paralleled multiband dipoles, at right angles, but
if I can only run one wire, I'll make a multiband dipole split
up with clipable insulators. If thats not workable, I suppose a
trap dipole could be used, but thats always my last choice
for a multiband dipole setup, being I like every drop of
efficiency I can muster. But the losses with those is not that bad.
With my mobile antenna, I could easily use *just it* if I wanted,
on any band. But my mobile ain't no stunted hustler antenna.
When I'm parked, my usual coil position is higher than the total height
of the average hustler whip. My mobile eats hustlers for lunch
and spits out the seeds... It's ugly. I did some tests using
hustler coils
vs my usual homebrew...Wasn't pretty... Adding the hustler coil
is like turning the antenna into a dummy load, *even* considering
that in most mobile setups, ground loss overshadows coil loss.
So if you see a *drastic* decrease in perfomance when changing
coils, Houston, we have a problem. I've seen many claim the "small"
hustler coils are actually more efficient than the "super" coils, which

was the type I tried. Luckily , I didn't pay for it, and I gladly gave
it back after testing... I think he stuck it on a hustler vertical...
Poor
thing.... I'd forget the "can" antennas, etc...A good mobile whip
would
likely do about as well. I'd use wire, or regular masts to make a tall
vertical. To me, cans sound like a soldering nightmare... :/ MK