I am planning on buying this license plate mount:

http://www.pro-fit-intl.com/lpant.html

and am looking for an all-purpose mobile whip, with particular attention
paid on 160-170mhz. I am thinking about a Firestik.

Comments or suggestions?

Thanks.

Seems overpriced. Not the best location either...depending on where you
live. Lots of opportunity for corrosion. Not to mention, having all that
steel along side the antenna element.

Bill Crocker


"User" wrote in message
...
I am planning on buying this license plate mount:

http://www.pro-fit-intl.com/lpant.html

and am looking for an all-purpose mobile whip, with particular attention
paid on 160-170mhz. I am thinking about a Firestik.

Comments or suggestions?

Thanks.

Bill,
I would have thought you'd have known better...living in the motor
city after all...there's no steel in that location...it's all plastic!


Joking aside, I agree with Bill actually. My concern would be ground
plane. This setup doesn't look conducive to transmitting.
Scott Ferguson

On Thu, 16 Dec 2004 20:49:46 -0700, "User" wrote:

I am planning on buying this license plate mount:
http://www.pro-fit-intl.com/lpant.html

Seems to me it would be a PITA if you are moving stuff in and out of
your trunk.

Tony

Joking aside, I agree with Bill actually. My concern would be ground
plane. This setup doesn't look conducive to transmitting.

Receive only, I'm not transmitting. And its on a hatch back so the antenna
will rise with the door.

Will this work for receiving?

Will this work for receiving? The answer is probably yes, but then so will
a coathanger taped to the window on the inside. The question is how well
will it work.

By putting the less than 3 foot long antenna that low and that far down (in
relationship to a lot of the bodywork) you will be getting some interaction
between the antenna and the coachwork. This means that the antenna will not
work as well in any direction as if it were mounted over a flat plate, such
as the roof. Additionally, you will get serious shading from the coachwork.
This means if the antenna is to be mounted as it is on those pictures that
it would work better when the source was behind the vehicle, in some cases
(application dependant) significantly better. In effect the antenna will
act as a low (or less than unity) gain antenna, with the sweat spot behind
the car. This is annoying in a mobile application.

Essentially you want as little of the car above the base of the antenna as
possible. And you want the antenna as central as possible to keep an omni
pattern. It is not practical (in many applications) to put the antenna in
the middle of the roof. But that is about the best possible place on the
average sedan.

For most installations (scanner stuff, anyway) I use a mag mount antenna in
the center of the roof if I can. As I drive a couple of convertibles, in
addition to hardtops, this is not possible. On those vehicles the antenna
is a mag mount on the trunk lid.

You could do a mag mount on your hatch back (I think you said it was a
hatch). Put the antenna in the center of the roof, and bring the coax in
around the hatch. Weather sealing will have to be watched closely. This
gives you the option of removing the antenna and throwing it in the back any
time you want also.

C!

"User" wrote in message
...
Joking aside, I agree with Bill actually. My concern would be ground
plane. This setup doesn't look conducive to transmitting.

Receive only, I'm not transmitting. And its on a hatch back so the
antenna will rise with the door.

Will this work for receiving?

Thanks very much for the advice. I've got a 4' Firestik. So at least 24-30
inches of antenna would be above the body of the car. But I could easily do
a mag mount on the roof as I have a sunroof that I could run the wire
through. The question is, what kind of mag mount is solid enough to handle
the wind load of a 4' antenna? And how does one shield the car's paint from
the magnet? A rubber pad?

Thanks again.

If you have a Firestick scanner antenna that is 4' long you must have the
MSM-4B.

The fact that 24" of the antenna would still be beside the coachwork will
hurt you almost as much as if the whole thing was alongside the body. But
it is still better than no external antenna at all.

Most better mag mounts come with a rubber (often) or felt (seldom) pad on
the bottom of the magnet, to protect the cars paint. Some only have a sheet
of soft aluminum. In general they will not harm the paint via contact, but
the big problem is when applying and removing the magnets people have a
tendancy to twist the mount off, this can cause scratches. Or when applying
the magnet people sometimes let one side pull down first, again hurting the
paint. Once the magnet is actually adhered to the vehicle it will not move
around, and so does not cause scratching, as long as the area you apply the
magnet to is clean.

Worse than possible scratching is paint fade...and the fact that it will not
fade under a mag mount that spends a lot of time on the car. My 1989 had
five antennas on it much of the time, three at all times, during the 9 years
I drove it. The antennas, all with mag mounts, were often removed if I was
parking in what I felt was a high threat area. So they came off and on the
car a lot. During that time the paint did get a couple of scratches, but
nothing that could not be easily buffed out. However, I habitually put the
same antennas on the same points of the car for all that time. After a
couple of years there were patches of less faded paint in each of those
locations. And there was really just nothing I could do about that. If the
car is less than a couple of years old this will be an issue. I believe car
paint does most of its color fading in the first three years.

A 48" antenna is not very tall, it should be easy to find a mag mount for
it. I would be willing to bet that Firestick sells one for them, although I
could not find one on their site at http://www.firestik.com/, and I know I
just saw one in the local Radio Shack that would do it. A quick search of
www.aesham.com shows they sell several different models (Cushcraft, Pro-Am,
Antenex, etc), from single magnet 3 and 3/4 inch models to triple 5" magnet
models. I would suspect that a single 5" would be overkill. I use a single
5" to hold an M-Squared 2M Sqloop, and the wind loading for that should be a
couple times a single 4' Firestick. The only time I have ever had an issue
was a single 3 and 3/4" mag with a 52 inch antenna on it, anything over
about 85 mph and that thing would come off. Once I put it on a 5" mag it
never came off again. However, don't get bit by the "bigger is better"
thing with these mounts, a triple 5" can be a real pain to get off the car
without damaging the paint.

C!

"User" wrote in message
...
Thanks very much for the advice. I've got a 4' Firestik. So at least
24-30 inches of antenna would be above the body of the car. But I could
easily do a mag mount on the roof as I have a sunroof that I could run the
wire through. The question is, what kind of mag mount is solid enough to
handle the wind load of a 4' antenna? And how does one shield the car's
paint from the magnet? A rubber pad?

I really appreciate the information! I have a 5" mag mount in mind
(http://www.westcoastmall.net/shop/pr...roducts_id=289) and was
wondering if a spring would be absolutely necessary?