One other thing to remember on mobile antennas - regardless of how "good"
the antenna is, it will not work properly without a good counterpoise /
ground plane. Usually this means the frame of your car, so be sure you
have a good, low-inductance connection to the frame. Some people have had
to use copper tape attached from the mount across the underside of the
vehicle in order to get a good connection. The mobile setup I used in my
testing last weekend had a heavy connection (almost as large as a car
battery cable) from the mounting flange on the bumper to the frame of the
vehicle.
On a related note, after looking hard for different mounts for my HF
antenna on a "rubber bumper" car, I was getting discouraged. Yesterday I
started calling custom hitch places until I found one hungry enough to look
at what I was doing. Within 30 minutes he had an "L" bracked fashioned
that was welded behind the steel bumper under the plastic fascia, and it
exits the vehicle just under the bumper and is sturdy enough for me to run
my Texas Bugcatcher, Hustler, or Outbacker with no problem. Hopefully it
won't drag on the road - if I were to do it again, I'd bring it up just
behind the bumper rather than just go back for 4" or so. So, in case
someone else is agonizing over the same problem, here is an easy solution.
It only cost $40, half the price of some of the other options, and about
the same as a mag mount. (One caution: be sure you are cautious about
welding on any modern car with all its electronics and microprocessors.
This welder had a suppressor which he connected across the battery to
prevent induced or radiated damage....)
73, Duane AC5AA
Duane A. Calvin
Server Systems Test Engineer
Dept. 76TS RS/6000 - SP Nodes
IBM Austin, TX >O< Tie: 793-3368
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