Antenna Effectiveness
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ABSOLUTELY!
There are a lot of factors that go in to predicting range. The biggest issue, as it relates to your specific question, is probably "it depends on the frequency you will be monitoring". A simple (very simple) answer is that the higher the frequency, the more effective your rubber hand-held antenna will be. For example, it is for all intense purposes useless for CHP because they are on low band VHF.
If the only band you are going to monitor is 800 MHz, then certainly an antenna dedicated to that band, such as the RS800, will be a better choice over a 'broad band' antenna. But an outside antenna designed for those frequencies will be even better.
ka3jjz
Wiki Admin Emeritus
I would start here by reading this thread...
http://forums.radioreference.com/general-scanning-forum/115818-how-far-can-i-receive.html
Those little duckies that come with handhelds are no better, in many cases, than a wet noodle on most frequencies - they are designed to be a compromise, and no more than that. There are handheld antennas that are designed for more broadband operation but putting them in a metal cage (a car or truck) just wipes out the advantage. You need to get the antenna outside.
Typically, duckies won't hear more than a couple of miles, dependent on numerous factors, which the thread above will no doubt address. Could be, and may very well be, less.
While a trunk mount will work, much better is to get the antenna on the roof, in order to take more advantage of the larger ground plane the mount would provide, as well as getting the additional height. However you must consider your normal driving habits - do you typically park in a garage or covered lot? If so, putting the mount on the roof might be a problem if you have a somewhat taller antenna. Are you constantly in an urban area? If so, a taller antenna, with somewhat more gain, might prove to be too much for the scanner. It may overload or desense. This is especially a problem with some GRE radios
I had such a situation a few years ago. I was working in College Park, Maryland, and also had to commute to DC from time to time, forcing me to adjust what antennas I used with my scanner. I used the Spectra whenenver I was in College Park, since that was an open lot, but had to resort to a small antenna (like the Austin Metropolitan) when I went to DC and had to park in a garage. At the time, I had a simple trunk lip mag mount, and didn't think I would have a problem with the Spectra in DC, but it was simply too much for the radio I was using (a Yaesu VX5R, so I could keep in touch with some DC ham friends of mine) - I had to use the Metropolitan, which worked quite a bit better.
Take the time to consider your normal driving habits and route - certainly a trunk lip mount (mag or physical trunk mount) will be better than a simple duckie. The other thing is that a mag mount can scratch the heck out of your trunk if you don't put something under it to pad it. That's because grit can accumulate under the mount over time.
73 Mike
On my Jeep I run a magnetic mount antenna on the roof. It's considerably better than an antenna anywhere inside the car.
In my other car I don't want to threaten the paint in any way so I use this:
Valor BNCSCRS suction cup mount
and one of these Diamond RH77CA SRH77CA Antenna
stuck to the inside of the windshield.
Putting the antenna up inside the windshield is much better than having it down inside the car where a handheld would locate it.
In my other car I don't want to threaten the paint in any way so I use this:
Valor BNCSCRS suction cup mount
and one of these Diamond RH77CA SRH77CA Antenna
stuck to the inside of the windshield.
Putting the antenna up inside the windshield is much better than having it down inside the car where a handheld would locate it.
First off, thankyou Ka3jjz for the link and advice thats very in depth information that I have to take time to review.
Is there a suction cup type thing that will stay well on the finish of my car because I dont want to threaten the paint at all either.
Also if I am traveling through different states then that would constitute a broad range antenna?
Is there a suction cup type thing that will stay well on the finish of my car because I dont want to threaten the paint at all either.
Also if I am traveling through different states then that would constitute a broad range antenna?
The suction cup mount I am using goes on the inside of windshield glass. Never touches paint.
Any suction cup or magnetic mount can move and hurt paint though on my Jeep you can't tell the mag mount has been in use off and on for several years because (a) I've heavily waxed the area (b) I wipe all dirt off both paint and magnet before attaching and (c) I carefully tip the magnet off the paint. But eventually it'll show.
Travelling thru different states is known as "travelling interstate" and has no connection to antennas that I can think of
(I don't understand your question)
I use a mag mount and when I remove it and clean where it was, you'd never know it was there.
There are a lot of issues with the antennas that pass their signal through glass. Some say they don't work as good. Also, the antenna needs to have quite a margin between itself and your vehicle, because sooner or later the two are going to collide. That will hit the paint. Lastly, a mag mount on the roof is going to be higher and have better reception that a glass mount, because it is not as high.
Travelling thru different states is known as "travelling interstate" and has no connection to antennas that I can think of
Hahah sorry man I wrote that half asleep. What I meant was if I am travelling interstate and I want to listen to public saftey channels during the trip then I would most likely need to find a broad range antenna? As opposed to a focused range antenna?
For VHF and UHF best reception is based on altitude - High as possible.
WTCPT
Member
I would install an NMO mount antenna, 100,000 cops can't be wrong!
When discussing antennas 'broad' usually refers to the range of frequencies it covers.
'narrow' likewise.
So..... guessing that you really meant 'range of coverage' then yes, you want an antenna that receives well. The ideal would be a great big, tuned-for-the-application, antenna on the center of the roof of your car.
(Most of us compromise from there)
I've taken many long driving trips with my scanners over the years. The magnetic mount antenna up on the roof of my Jeep works really well. Only funny issue was one time in Utah driving 60 into a 50 mph headwind the antenna just couldn't stay attached in the 110 mph effective wind. So I stuck it in the 'streamline' position on the back liftgate. Same with the mag mount CB antenna. (Jeep looked like a big bug with long waving antenna parallel to the ground) Sometimes you just have to compromise
Depending on what states you are referring to, antenna performance might be very important. Or it might not. If you're going New Jersey to Virginia chances are it won't matter because population density means there's always something transmitting nearby. If you're going Nebraska to Wyoming, your scanner will be really quiet a lot of the time even with the best antenna you can buy.
(there's a lot of empty space between towns big enough to have a radio tower)
tmfok7
Member
Anytime you can get the antenna outside the vehicle, you gain an advantage. That being said, you might look at the ScannerMaster webpage and under "Antennas", check the Mobile Mounting Gear and if you are willing to at least put a mount on your trunk lip, check the 'NMO Trunk Lip Mount'. I think most everyone would tell you this is the next best thing to drilling a hole and putting a mount on the body and better than a Mag Mount. If that is out of the question, then check out the 'Duckie Window Mount w/BNC' under "Portable Mounting Gear". This along with the RH77 antenna (or something like it) suggested by NW0U would still be better than the Suction Cup Mount inside the vehicle and you can still take it with you if you change vehicles or have to use a rental vehicle.
WTCPT
Member
Seriously I'd get an NMO mount (you punch a hole in your car, it's used by serious users like cops, taxis, etc) then get an antenna for VHF and it should work just fine for the rest of the freqs.
If your car is too nice to punch a hole in, get a cop-surplus Crown Vic, it'll have the hole already there.
If your car is too nice to punch a hole in, get a cop-surplus Crown Vic, it'll have the hole already there.
Antennas
Keep in mind that the actual antenna is only doing 1/2 of the work. The other half is being done by the metal of the vehicle, which acts as a ground plane. In a perfect installation, the antenna should be mounted with an eequal amount of metal all the way around it. If the antenna is "off to one side", then your reception will tend to be directional.
I won't tell you that. Unless your auto is very low profile and the roof is not all that much higher than your trunk, getting your antenna higher will give you better reception. I'd go for a good mag mount over a trunk lid mount any day.
Keep in mind that the actual antenna is only doing 1/2 of the work. The other half is being done by the metal of the vehicle, which acts as a ground plane. In a perfect installation, the antenna should be mounted with an eequal amount of metal all the way around it. If the antenna is "off to one side", then your reception will tend to be directional.
It sounds like you are back to an antenna inside the vehicle, or one that conducts through glass. Now if you are only interested in UHF (which includes 800 MHz), then you might get away with the RH77 or other rubber antenna. Otherwise I stand by the two mag mounts I use.
I agree.NW0U said:
WTCPT
Member
If I ever get a car again it's NMO all the way.
I like donuts too.
I like donuts too.
The link describes an antenna that is tuned for 800 Mhz. That means that it's tuned for 800 Mhz, not 150, not 450.
The only way to know for sure would be to test the antenna against your stock rubber duck.
The RH77 I linked to in my post does quite well at all those bands. Better than stock anyway and does better on 150 than the Radio Shack 800 Mhz tuned antenna.
Thanks all for the information im definatly looking into the magnetic trunk mount, it seems ideal.
Quick question: Do you think the same applies for a convertible? Or would the engine and rest of the body of the car still block the signal?
Quick question: Do you think the same applies for a convertible? Or would the engine and rest of the body of the car still block the signal?
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