Low Profile Antenna's

[Agentblack]

What are people's thoughts on low profile antenna's? I am looking at a couple different antenna's and id like to keep a slick top look to my car without a million antenna's 10 feet in the air. I'm not trying to communicate cross state, most of my communications would be limited to 25-40 miles max.

I am looking at the Larsen 416-430 Mirage Antenna. Its MFG. part number LP420NMO and Tessco Part: 464093 as well as Laird Tech 144-152 Unity 1/4 wave Mfg Part: qwb144 and Tessco Part: 87558. Im not able to locate a vhf "hockey puck" style antenna.

Anyone have experience with these two antenna's in the Ham bands? I'm also looking at two others for the upper parts of the frequency range for a couple other radios on my shopping list. The first is the Laird Tech 152-162mhz Unity 1/4wave MFG:qwb152 Tessco: 35951 and the Larsen 470-490 Mirage MFG:lp470nmo Tessco: 16986.

Also, if anyone has a lead on a wide band "hockey puck" style scanner antenna, please let me know. I'm not able to find anything.

Thanks.

 

[jim202]

What are people's thoughts on low profile antenna's? I am looking at a couple different antenna's and id like to keep a slick top look to my car without a million antenna's 10 feet in the air. I'm not trying to communicate cross state, most of my communications would be limited to 25-40 miles max.

I am looking at the Larsen 416-430 Mirage Antenna. Its MFG. part number LP420NMO and Tessco Part: 464093 as well as Laird Tech 144-152 Unity 1/4 wave Mfg Part: qwb144 and Tessco Part: 87558. Im not able to locate a vhf "hockey puck" style antenna.

Anyone have experience with these two antenna's in the Ham bands? I'm also looking at two others for the upper parts of the frequency range for a couple other radios on my shopping list. The first is the Laird Tech 152-162mhz Unity 1/4wave MFG:qwb152 Tessco: 35951 and the Larsen 470-490 Mirage MFG:lp470nmo Tessco: 16986.

Also, if anyone has a lead on a wide band "hockey puck" style scanner antenna, please let me know. I'm not able to find anything.

Thanks.

You might have the wrong impression about the performance of low profile antennas. Anything that doesn't have a good 1/4 wavelength or better long antenna is just some sort of compromise to the radiation effectiveness of the signal. With you looking to get 24 to 40 miles of range, you had better reconsider your selection of antennas.

I have used simple 1/4 wave long antennas for a good number of years on both the VHF and UHF band. As you can get these in black these days, they tend to blend into background. Even more so if you have a black roof. The range will depend on who or what your trying to talk to. If there are high location repeaters, then your going to do fairly well. If your talking mobile to mobile, your stretching your wishes. I run 100 watt transmitters and don't get that type of range vehicle to vehicle. It will also depend on the land around you. In flat desert, you might get some place close to the 25 mile range car to car. In the city, you will be lucky to get 5 miles car to car on VHF. It won't matter what kind of an antenna your running. In the mountains, it will depend on your actual location of both vehicles.

 

[Agentblack]

thanks for the advice. I was hoping to just get a moderate to decent range with the low profiles. I've seen some other 1/4's that are about 19" which i could go with, but it wont be as clean as I was hoping for. I wasnt going to put them on the roof of the car, rather, on the trunk lid.

I was just wanting to avoid having a bunch of wires sticking up off my car.

 

[LtDoc]

I have no direct experience with those antennas but have some indirect experience with them (listened to a few). They follow the same old general 'ROT' (Rule of Thumb) with any 'shortened' antenna. Half the size as a 'real live' antenna (1/4 wave) means about half the range/performance. A quarter the size, a quarter the performance. So, if that would suit your needs, then that type of antenna would probably work for you and 'clean' the 'looks' up some. There is no possibility of 'gain' from them unless they are phased in some way, and that's not going to make them even equivalent to a 'full sized' antenna. Maybe at 800 Mhz, but that's "iffy" too (cuz they wouldn't be 'shortened' as much). As for the brand, beats me! If I get a chance, I'll ask what brand is used locally (the only ones I've had experience hearing). I don't think all this is 'new' to you, just a reminder.
they would be more 'stealthy' than the typical 5/8 whip type antennas, more so since 'XM' radio antennas are included on most new cars. No idea about how practical/useful they may be.
- 'Doc

(That 'ROT' thingy is very rough, more of a guess than fact.)

 

[Agentblack]

Ya i knew that using the puck antenna's would decrease my range, but i guess i was overstating how far i thought 75 watts would go. I usually just travel around the midwest, which is usually flat, open fields, so i think the range would be ok.

What would one really think the range would be on antenna's that style? I have found also a few of the short "can" styles which could work too, however I cant find any down in the ham bands. Most start at 150mhz and go up and 450 up.

 

[mass-man]

And you may not find them for the VHF ham bands...per the previous posts, the low profile antennas are a compromise, ie, less range. Typically ham rigs fun 30-50 watts with a few as high as 70 and MANY much less than that, so reduced power, reduced antenna size, equals less range. Plus with many hams in metro areas add the obvious obstacles to effective range and I don't think they would buy them.

 

[petty4305]

In reference to the antenna question........ Have you ever thought of a glass mount antenna? I have 1 on my truck and I like it. It still gets good distance and still has the "low profile" look.

 

[Agentblack]

eh Ive thought of the glass mounts, but in order to avoid having the 3 ft+ antenna syndrome from dual band antenna's, im going to have to have a separate the different bands. (1 vhf, 1 uhf, 1 800mhz, 1 scanner) and i dunno if i have enough room on my back window to mount all of those. have suggestions for glass ones? I havent really found any that look quality.

The vhf rig im looking at is the v8000 (75w) since the prospects of getting my kenwood dual bander with the bad displays fixed is looking slim. Haven't fully decided on a uhf rig yet, however, im probably going to move away from the v8000 and find one that has a remote head as id rather not have the body mounted in the passenger cab.

 

[kb0nly]

eh Ive thought of the glass mounts, but in order to avoid having the 3 ft+ antenna syndrome from dual band antenna's, im going to have to have a separate the different bands. (1 vhf, 1 uhf, 1 800mhz, 1 scanner) and i dunno if i have enough room on my back window to mount all of those. have suggestions for glass ones? I havent really found any that look quality.

The vhf rig im looking at is the v8000 (75w) since the prospects of getting my kenwood dual bander with the bad displays fixed is looking slim. Haven't fully decided on a uhf rig yet, however, im probably going to move away from the v8000 and find one that has a remote head as id rather not have the body mounted in the passenger cab.

I would stick with another dual band radio, not to say the V8000 isn't a good radio, but nobody makes a single band UHF mobile in the ham radio market, and nobody makes single band radios with a remote head either, just a simple fact. You need to go dual band to get UHF and remote head, just the way it is. I wish the manufacturers would change that, but i guess there isn't much market for it. Although i have heard many hams over and over say how much they wished for a 2m only radio with remote head.

As for the antennas... You could go with a single dual band antenna for VHF/UHF, and a single wideband scanner antenna or Larson 150/450/800 and use a diplexer to share with the scanner. What bands will the scanner monitor? What was the 800 antenna going to feed a transmitter or just a radio for monitoring? If the 800 radio is just receive you could share it's antenna with the scanner and get your need down to two antennas, which could then be trunk mounted or otherwise.

25-40 miles on a 1/4w is pretty optimistic even for the midwest. We may be fairly flat but there is trees and terrain that don't help any. I can go out to my mobile right now and spin on a 1/4w and not be able to hit more than one local repeater, spin on my large Comet dual band antenna and now its a half dozen repeaters.

 

[SCPD]

I've been an amateur radio operator for 16 years. If I only had $XXX to spend on a mobile radio setup I would spend the majority of the money on the antenna system. I would prefer to let the antenna do the "work" instead of the radio, i.e., the higher gain antenna means less R.F. power you'll have to use and less wear and tear on the radio.

In my area I can get away with using a 1/4 wave on 2 meters for receiving but have to increase my transmit power to reach the repeater. The repeaters I use average 30 miles from me and I use a hi-gain Comet dual band antenna. My radio is a Yaesu FT 7800 and I RARELY use more than 5 watts on transmit. I've tried a 1/4 wave antenna (it's dedicated for scanner use now) and I had to use 10 watts on transmit to reach the repeater. There are pro's and con's as well as trade off's when using low profile/low gain antennas, you're the only one that can decide on where the line is you want to cross on performance versus looks.

 

[sragen]

What about a multiplexer? It's another device in the line and I'm sure its not as good as a "home run" line. I too do not like the "porcupine" look, but my requiremnents and environment are such it works well for me.

 

[Agentblack]

Well if i have my way, all of my radios will be trunk mounted with the heads in the passenger cabin. So there wont be many wires to come forward.

I'm basically looking to do the following:

Dual Band (or 1 each ham band vhf/uhf, obviously less is better.)
commercial VHF
Scanner

Which or where would you suggest a multiplexer?

 

[Agentblack]

what is everyone's thoughts on trunk lip nmo mounts? Good? Bad? horrible dumb idea?

 

[W2NJS]

Comtelco makes a UHF hockey puck that has 3db of gain. I use it and it's great. They'll also sell one to you direct if you phone them. Their complete catalog is accessible online. VHF low-profile antennas are usually a pain because of their narrow bandwidth, more so if you need to transmit with it. The higher you go in frequency the wider the bandwidth of these specialty antennas becomes. You'll have to do some digging to form your own opinions and get reliable information on this subject. All I'm relating to you is based on personal experience and is not based on hearsay.

 

[Agentblack]

On the VHF low profiles, I've noticed that as i've been researching, which means I am probably going to have to have 2 of them. One down in the ham bands, and the other up in the commercial band.

Are the antenna's Comtelco sells made actually by them, or are they rebadged antennex/maxrad's?

 

[Agentblack]

Hmm.. looked over their site.. interesting some of their products.. and i ended up answering my own question! Nice that they are american made.. might buy those instead of maxrad/antennex..

 

[bryan_herbert]

Unless the 'puck' radiates at 800 MHz or higher I can guarantee it does not have a gain of 3dB. Low profile antennas are designed to function but at a cost which is signal quality. Putting one on your trunk makes it even worse. Think of a kid sitting in the front seat of a car, what view do they have? The dashboard. How well can you see the street if you're not able to see over the dashboard? You cant. The same principle goes for antennas. Our sheriffs department here in Los Angeles likes to use LPAs on some of the unmarked cars. Even with multiple repeater sites providing overlapped coverage the signal into and from the repeater is still crap.

As for trunk lip mounts, they are okay but again designed at a cost because theyre mounted on the side of the trunk lid which means your radiation pattern isnt going to be clean. The best reception has always been and always will be in the middle of the roof where the entire car acts as a ground plane. Without a decent ground plane not only does the antenna impedance become mismatched (which does cause significant signal loss at higher frequencies) but the antenna loses the ability to receive and transmit via groundwave. The waveforms actually travel upwards in a near vertical pattern which is why you dont usually see ground planes on antennas at airports.

 

[Agentblack]

The best reception has always been and always will be in the middle of the roof where the entire car acts as a ground plane.

Sadly I have a big problem with that. My car has a sun roof that retracts between the roof top, and the headliner, so unless i put them all near the back window, i dont have much, if any room on the roof, save near the doors but it will look lopsided.

Which is why I was looking at the LPA's because i want it to be a clean appearance without 900million 10foot antenna's hanging off the car. I've seen some 1/4wave's that the whips are about 19" tall which would be acceptable if i cant locate a decent LPA.

Two issues i guess i need to figure out is 1) which antenna's and 2) which mounts. I'm not totally opposed to drilling through the trunk lid, but if i could avoid it that would be nice. I'm starting to wonder if i'm not asking for the impossible :-/

 

[bryan_herbert]

Its not recommended on most cars. But one way to counteract the lopsided radiation pattern with a trunk lip is to mount the same antenna on the opposite side of the trunk lid and connect them with an antenna coupler. You'll often see this on big rigs where they mount an antenna on each side, usually on a mirror. The general rule is 3 feet of separation which is why its not usually done on cars. It makes a drastic improvement on big rigs but on cars with less than 3 feet of separation the antennas act more like a yagi.

 

[Agentblack]

eh.. my car is about 6 ft wide.. 06 taurus.. so that probably wont work. Does the lopsided radiation pattern also affect the quarter waves or all antenna's in general?