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Commercial Radio Antennas - Please keep discussion related to professional, commercially used antennas and antenna systems for the two-way radio industry. Topics for the use of these antennas on amateur bands are accepted here.

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Old 12-15-2015, 4:39 PM
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Default Antenna choice for business band and Amatuer band

So some of you might have participated in my MURS frequency thread and have an idea of what I have coming up. I feeling comfortable enough with the radio and frequency situation to now start asking questions about Antennas. Application will be for the Baja 1000 world famous off road racing event in Baja Mexico out in the desert and mountainous regions (No mans Land), but also to be good for operating on in the Ozark mountains of Missouri. I would like it to have the biggest frequency range possible, but for the race we will be Tx'ing from 151.000Mhz to 154.000Mhz. That frequency range is where I need the best performance. I'd also like to be able to use it for Hamming around town on 144 to 148Mhz. If I can only get one or the other or I will sacrifice performance on the 151Mhz to 154 Mhz if I get one that will do both, I'd rather just get one that works outstandingly for the 151Mhz to 154Mhz. I'm pretty sure I'm going to have to go with a magnetic mount for ease of switching from my personal truck to the race chase vehicles. I know not how to tune an antenna or decide on whether or not to go 1/4, 1/2, or 5/8 wave. So as the recommendations and your questions come in, I will ask to learn about what makes the right antenna.

Thanks,

Kix
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Old 12-15-2015, 4:44 PM
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If you go with a quarter wave, it will have the bandwidth to cover both segments. If 151-154 MHz is your priority, get one tuned for about 151 MHz and it will work well in both segments. Even stock lengths will work well. The higher the gain, the narrower the bandwidth.
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Old 12-15-2015, 6:41 PM
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I concur. 1/4 wave will give you good performance over the widest frequency range. I've got a 1/4 wave mounted on the roof of a full size truck and it works very well. I put it on my spectrum analyzer with the tracking generator and swept it across the VHF band, and it showed 2:1 or less from 144 up well past 160MHz.

Nice thing is they are relatively inexpensive. $10 will get you a good one, name brand, well built.

1/2 wave might be another option. Useable bandwidth isn't quite as good as the 1/4 wave, but they are still pretty capable. Nice thing about a 1/2 wave is that they will work without a ground plane, however they work better with one.

I'd skip the magnetic mount. You'll spend $40 on a professional mag mount, but you can buy permanent mount NMO's for $15 or less. The permanent mount antenna will outperform the magnetic mount and give you a lot less issues over time.

While the mag mounts are pretty good, you'd really be putting them through a lot of stress bouncing around off road. It is possible to knock a mag mount loose, and they can scratch things up pretty well, especially in dusty environments.

I'd say you'd ultimately save money and get better performance by installing a permanent mount on the vehicles you plan to use the radio in. Use either a 1/4 wave or 1/2 wave antenna and you'll be happy.
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Old 12-15-2015, 10:42 PM
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Quote:
Originally Posted by mmckenna View Post
I concur. 1/4 wave will give you good performance over the widest frequency range. I've got a 1/4 wave mounted on the roof of a full size truck and it works very well. I put it on my spectrum analyzer with the tracking generator and swept it across the VHF band, and it showed 2:1 or less from 144 up well past 160MHz.

Nice thing is they are relatively inexpensive. $10 will get you a good one, name brand, well built.

1/2 wave might be another option. Useable bandwidth isn't quite as good as the 1/4 wave, but they are still pretty capable. Nice thing about a 1/2 wave is that they will work without a ground plane, however they work better with one.

I'd skip the magnetic mount. You'll spend $40 on a professional mag mount, but you can buy permanent mount NMO's for $15 or less. The permanent mount antenna will outperform the magnetic mount and give you a lot less issues over time.

While the mag mounts are pretty good, you'd really be putting them through a lot of stress bouncing around off road. It is possible to knock a mag mount loose, and they can scratch things up pretty well, especially in dusty environments.

I'd say you'd ultimately save money and get better performance by installing a permanent mount on the vehicles you plan to use the radio in. Use either a 1/4 wave or 1/2 wave antenna and you'll be happy.
This. As stated in the other thread, I have some friends that run in the Texas circuit. The terrain is just as rough and unforgiving as what you would find on the Baja Peninsula (and nearly as desolate). They run NMO.

Also have a friend who would not drill his Dodge (he just couldn't bring himself to do it). Being that he trades the trucks off every 2 years I kinda understand (I go through a half ton every 3 years). I finially convinced him to move to a Dodge fender bracket...it works well.

I grew up in the Mojave desert. It seemed that at least every other trip we would throw an antenna (mag mounted) on one of my father's trucks. My father was always amazed that he'd never throw his commercial antennas (CalTrans used to deck the company trucks out, VHF Spectras, Low band Maxtracs, Pulsars, etc).

Needless to say, all of the ranch trucks have NMO mounts on them now.

Quarter wave antennas work well. On simplex you might notice a difference on a 5/8th wave but on a properly designed system, you'll never notice the difference between a 5/8th wave and 1/4 wave.

Larsen makes a wideband 5/8th wave. It's only 2.5 dBd of gain instead of the full 3 dBd but it does cover 25 MHz of bandwidth.
Model is NMO150-WB.

I'm really fond of the Larsen NMO-Q line of 1/4 wave antennas. Add a spring and they are fairly rugged (had one on the XJ for 3 years without issue).
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Old 12-15-2015, 10:53 PM
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UHF/VHF Wide Band 1/4 Wave Antenna with Spring (132-525Mhz) 1/4 Wave UHF and VHF Wide Band Antenna with Shock Spring (132-525 Mhz) [WB-1/4-W-HD] - $48.00 : Rugged Radios: Headsets, Intercoms, 2-Way Racing Radios and Communication for Motorcycles, Off

Something like that with the big spring at the bottom gives you 15-20 MHz bandwidth on vhf...
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Old 12-15-2015, 11:58 PM
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Originally Posted by W5PKY View Post
Also have a friend who would not drill his Dodge (he just couldn't bring himself to do it). Being that he trades the trucks off every 2 years I kinda understand (I go through a half ton every 3 years). I finially convinced him to move to a Dodge fender bracket...it works well.
Let me get this straight - you guys abuse trucks on the terrain, but don't want to abuse it by drilling a hole that won't affect the trade-in value nearly as much.

Did I understand that correctly?

BTW, that will strengthen my recommendation of the quarter wave. Less bending moment and much more durable than any other antenna made.
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Old 12-16-2015, 12:33 AM
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More than likely the wife wouldn't let him....
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Old 12-16-2015, 12:49 AM
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More than likely the wife wouldn't let him....
He's actually single. Just can't bring himself to do it (maybe his next truck, next year, I'll get him to do it).

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Originally Posted by Voyager View Post
Let me get this straight - you guys abuse trucks on the terrain, but don't want to abuse it by drilling a hole that won't affect the trade-in value nearly as much.

Did I understand that correctly?

BTW, that will strengthen my recommendation of the quarter wave. Less bending moment and much more durable than any other antenna made.
Nope. Terrain-wise, we are pretty nice to our trucks. We rack up the miles though. He averages around 60,000 miles a year. I average around 50,000 miles a year. He trades before the powertrain warranty expires. I trade either when the engine or transmission goes (depending on current value of the truck) so around 170,000 miles. I drill mainly because I'm a stickler for installs looking professional and clean.
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Old 12-16-2015, 1:40 AM
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OK. So with 120 to 170K on them, trade in value is a concern?

Tell him to man up and drill, baby, drill.

The only time I ever got nervous about drilling was on a brand new Mercedes. But, you are correct that no other install looks as nice and is as durable. Even angle mounts will often start to wobble after some time (especially when you have PS people who just HAVE to play with the antenna).
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Old 12-16-2015, 1:46 AM
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He's actually single. Just can't bring himself to do it (maybe his next truck, next year, I'll get him to do it).
To be truthful, if your friend puts a hole in the roof, there are rubber plugs made just for plugging the hole when you take the antenna out. Look at an old police car, you'll see them. And with this being a truck, and the hole being on top of the roof, whoever he's selling to, or turning it into, isn't going to go get a ladder and look on top of the roof.

And I agree with the 1/4 wave suggestions. $10. Good to go.

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Old 12-16-2015, 9:06 AM
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Thanks fellas! So now for the technical questions. I have done some digging in here to research these topics, but it's kind of like reading something in Spanish. I'm totally new to this stuff so go easy on me. I may have follow ups to some of these answers to better understand the lingo.

1.What does NMO stand for and are there other acronyms for antenna bases to watch out for? I think I saw a few more while looking and have no idea what is what.

2.What is a ground plane and how does it effect the performance?

3. Would a mag mount be ok since the mobile radios are only going in the chase vehicles that will be on the highway. Might have to go a couple hundred feet off the highway to a pit every now and again, but we aren't busting *** through the desert and dropping in holes. I definitely don't want to do permanent because I will be taking this off my personal truck and putting in on someone else's truck for the trip. I would like to be able to swap it over to the next truck in under an hour.

4. Do they have mounts that clip in a door sill kind of like a roof rack clip and would they be better then a mag mount? Would it really end up being the same performance in the end because you can't locate it in the center of the roof?

5. How would one go about tuning for 151Mhz like said above and in everyone's opinion, will tuning be necessary in my situation? I want to do this right, but I will not have any special equipment to measure performance.

6. Why do the permanent mounts outperform the mag mounts?

7.Would having a tall 49" replacement whip be better then a 18.5" whip on a spring? Height will be no issues because there will be nothing to catch the antenna like trees and such. Just Cacti, but they won't go over the truck.

8. Do some types of mag mounts out perform others and why?

9. What is antenna gain and why is it important?

10. Is the higher the gain the better? Like is a 3db better then a 2.5db? Can you get an antenna for my situation that is higher than 3db gain?

Thanks,

Kix
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Old 12-16-2015, 11:40 AM
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Originally Posted by kixntuff View Post
Thanks fellas! So now for the technical questions. I have done some digging in here to research these topics, but it's kind of like reading something in Spanish. I'm totally new to this stuff so go easy on me. I may have follow ups to some of these answers to better understand the lingo.

1.What does NMO stand for and are there other acronyms for antenna bases to watch out for? I think I saw a few more while looking and have no idea what is what.
New Motorola is what NMO stands for. It's the most popular type of professional mobile antenna mount. Tried and true in just about every single application. Installed properly, they'll outlast the vehicle.
NMOHF is a higher frequency model that's designed for GPS and higher frequency use. They are cross compatible with standard NMO's. You don't need one of these.
LM Mount. It's a stud mount. Falling out of favor. They'll work fine, but not quite the selection of antennas that you'd get with the NMO.

Stay away from SO-239/UHF mounts. They are somewhat popular amongst amateur radio operators. They are weak and not inherently waterproof. Often won't stand up to the beating of real world use, especially off road. Limited selection of antennas. Stay away from these, no matter what the amateur radio operators say. Not suitable for your use.

3/8x24 mount. Common with CB radio antennas. These are suitable for some types of antennas, but again, not a good choice.

Stay away from anything proprietary. NMO mount is the way to go.

Stick with the known good brands, Larsen, Antennex, Comtelco, etc.
Stay away from anything with the Browning or Tram name on it. They are Chinese knockoffs that have bought the rights to an old USA based CB radio manufacturer from the 60's.

Quote:
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2.What is a ground plane and how does it effect the performance?
It's basically the other half of the antenna. Many antenna designs require two parts: The radiating element and the radials or ground plane. Pickup truck cab roof is an excellent ground plane -IF- you mount the antenna right in the center. Ideally you want ground plane extending out equally in all directions under the antenna. This is why you'll see police cars with the antenna mounted in the center of the roof or trunk. Mounting the antenna off to one side, like a fender mount, causes some directionality to the antenna installation. Might work in your favor if the truck is pointed in the right direction. Won't help if it isn't. Center of a large metal plane is best. Doing -anything- other than this is compromising your system.

Only exception is non-ground plane dependent antennas. Basically a 1/2 wave design. They'll work OK without a ground plane, but they work much better with one. Don't use a 1/2 wave design and think you are getting something for free. You ain't.

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3. Would a mag mount be ok since the mobile radios are only going in the chase vehicles that will be on the highway. Might have to go a couple hundred feet off the highway to a pit every now and again, but we aren't busting *** through the desert and dropping in holes. I definitely don't want to do permanent because I will be taking this off my personal truck and putting in on someone else's truck for the trip. I would like to be able to swap it over to the next truck in under an hour.
They are OK if you place them in the center of the roof. There is a small reduction in performance with magnetic mounts. The bigger issue is that you'll run the coaxial cable through a window or door, and this will eventually cause damage to it. This damaged coaxial cable, either pinched, crushed, cut or otherwise damaged, will cause at best impaired performance. At worst it'll damage your mobile radio.

I only use magnetic mounts for testing purposes or very short term installs. It is not a good solution in any sense of the term.

A good NMO magnetic mount will cost $40 or more. You can purchase several NMO permanent mounts for that cost. Magnetic mounts are not a cost savings. They are a quick and dirty solution for a temporary problem. They are also a half-assed solution for guys who's wives won't let them drill a hole in her mini-van.
Don't be that guy. The "but it's a leased vehicle" argument doesn't hold up. I've installed many NMO mounts on lease vehicle and never once had a problem at the end of the lease.

Yeah, they'll work, but you will get better performance from a properly installed antenna. You wouldn't run the Baja race with an old lawn mower engine in place of a real built motorcycle engine. Why do the same with your communications system?

Quote:
Originally Posted by kixntuff View Post
4. Do they have mounts that clip in a door sill kind of like a roof rack clip and would they be better then a mag mount? Would it really end up being the same performance in the end because you can't locate it in the center of the roof?
Yes, there are mounts like this. You'll find them in the amateur radio catalogs next to the magnetic mounts. They are intended for the guys who's wives won't let them install a real antenna on her mini van.

The issue with these is they rarely make a good ground connection to the vehicle. At best they result in a lopsided ground plane under the antenna. Then they still have the draw backs of trying to get the coaxial cable into the vehicle through the door or window. Basically if you are using these, you should probably turn in your "man-card". They'll work, but work poorly, plus others will point and laugh. No seriously, no one should be laughing, but if you are going to do a half way install like this, at least go with the magnetic mount and put it in the center of the roof.

Quote:
Originally Posted by kixntuff View Post
5. How would one go about tuning for 151Mhz like said above and in everyone's opinion, will tuning be necessary in my situation? I want to do this right, but I will not have any special equipment to measure performance.
To do it correctly you either need an SWR meter or a return loss bridge and some other equipment. The SWR meter is the cheapest solution, but you are still looking at >$70 for a half way good one. It's a good investment if you are going to be serious about this. Should be one of the first tools you purchase. Tuning your antenna properly will make a big difference in performance. Not tuning an antenna is doing a halfway install.

On the flip side, antenna designs like 1/4 waves are pretty broad banded by nature. You can often cut them using the included cut chart that comes from the manufacturer and get "close enough". Being off by an 1/8 inch or so isn't the end of the world. Still, I always put mine on my analyzer to make sure. Checking the entire install with the right test gear will help find any hidden issues that you might miss, including issues with connectors, corrosion or damaged coaxial cable.

Quote:
Originally Posted by kixntuff View Post
6. Why do the permanent mounts outperform the mag mounts?
Proper connection to the vehicle ground. Mag mounts make this connection by using capacitive coupling. It works well enough when dealing with RF. Jumping the gap between the magnet base, through the paint and too the roof does pretty well. There is a very slight amount of loss. Truth is it would take some specialized test gear to see this minimal amount of loss.
The benefit to a permanent mount is that it looks professional. It'll work better. It'll prevent damage to the paint. It'll prevent damage to the coax. It'll tell the world that you value radio performance and professionalism. It'll also tell the world that you retained your "man card" and your wife doesn't get to call all the shots (but still most of them).

Quote:
Originally Posted by kixntuff View Post
7.Would having a tall 49" replacement whip be better then a 18.5" whip on a spring? Height will be no issues because there will be nothing to catch the antenna like trees and such. Just Cacti, but they won't go over the truck.
Antenna length depends on the frequencies being use and the type of antenna design. You can't just swap out whips and expect the system to work correctly. A quarter wave antenna on VHF will be about 18 inches or so. If you change that length you are changing the characteristic resonance of the antenna, basically making it work on a different frequency.
If you want a lower antenna, stick with the 1/4 wave design.
If you want a longer antenna, look at a 1/2 wave or 5/8 wave. They require coils at the bottom of the antenna to make them tune up correctly.

The 1/2 wave and 5/8 wave antennas will give you more gain, basically focusing more of the RF energy down towards the horizon. This effectively increases the overall system RF output. It works well in lots of flat terrain, but it can be a hindrance in the mountains. Likely you wouldn't be able to tell the difference. A 5/8th's wave antenna design might work a bit better for you guys for what you are doing and the locations.

Quote:
Originally Posted by kixntuff View Post
8. Do some types of mag mounts out perform others and why?
They all sort of suck. A bigger diameter base will couple a bit better to the ground plane under the antenna. Using really small bases probably doesn't work as well. Also, the bigger magnet will give you more holding power. It'll also damage a bigger area of paint on the roof. Mag mounts are notorious for leaving scratches on the roof. Dust gets under them and can do damage. Since you'll basically be swimming in dust down there, I'd make sure you are comfortable with some scratches on the roof of your truck.

Quote:
Originally Posted by kixntuff View Post
9. What is antenna gain and why is it important?
Antenna gain is basically the design of the antenna focusing more power in certain directions. For mobile antennas, the antenna design will determine the amount of gain. By comparison, a 1/4 wave antenna is considered to have zero gain. A half wave antenna with no ground plane will also have zero gain. A half wave antenna with a ground plane will have about 2.4dBd gain. A 5/8ths wave antenna will have about 3dBd of gain. For ever 3dB of gain, you are effectively increasing the radiated RF energy by 2 fold. This is done by focusing more of the RF energy at the horizon, rather than in a more circular shape as a quarter wave would have.

Think of a light house. A 1000 watt incandescent light bulb is pretty bright, but from 15 miles away it's going to be hard to see. Now use a mirror behind it and lenses in front of it to focus the light into one direction. Suddenly that dim 1000 watt light bulb 15 miles away is brighter. Draw back is that the area actually lit by the lamp is decreased. Not an issue if the people you are trying to shine the light at (talk to with your radio) are on the horizon. If they are well above or well below the horizon, it's not going to work so well.
This is one of the reasons why a quarter wave antenna will often outperform a higher gain antenna in high mountains.

For where you guys are going to be and what you are doing, a 5/8ths wave antenna might work better. It'll sacrifice bandwidth, but will probably work a bit better. Since you want one antenna for for amateur radio and commercial/race use, you might be limiting yourself. 2 separate antennas that you swap out depending on your needs would solve this. One tuned for 2 meter amateur use, one tuned for your race frequencies.

A half wave antenna is sort of a good compromise. It'll probably work well on amateur and the lower frequency commercial stuff while still providing some gain.

A quarter wave will give you the bandwidth to do commercial/race stuff as well as amateur radio use in one antenna.

Over the years I've tried many different antenna designs, and I really don't hear a difference. I've stuck with quarter wave antennas since they serve my needs best. I can have one antenna for amateur radio use as well as the work/commercial stuff I do. I've tried 5/8ths wave antennas and they work well, but the additional length is a problem for a full size truck in a suburban area.
Where I have had luck is mounting 1/2 wave antennas on a Polaris Ranger roll cage. Since the roll cage doesn't supply a very good ground plane, I've seen slightly better performance by using this antenna type.

As they always say, your milage may vary.....

Quote:
Originally Posted by kixntuff View Post
10. Is the higher the gain the better? Like is a 3db better then a 2.5db? Can you get an antenna for my situation that is higher than 3db gain?
Depends on what you mean by "better". For my own personal use (see above) a quarter wave antenna is "best" for me. Someone who sticks to the 2 meter amateur frequencies and not need to transmit anywhere else or they live out on the plains might say a 5/8ths wave is "better".

The difference between 2.5dB and 3dB is probably something you wouldn't be able to hear with your ears. Would take some test equipment to see the difference. On the other hand, that 0.5dB might make an unreadable signal slightly better, maybe enough to make out a few words. It likely isn't going to be a night and day difference. Chasing fractions of a dB like this can get costly and usually doesn't pay off well enough to be worth it (in most cases). If you are really wanting to chase down every little bit of signal you can, skip the magnetic/bracket mounts and do a proper installation. The better ground plane and safer cable routing will probably pay off more. Adding a higher gain antenna would add to that improvement. Staring with a poor antenna mount and trying to make up the loss in performance by adding bigger antennas is probably not going to pay off too well.

Quote:
Originally Posted by kixntuff View Post
Thanks,

Kix
Hey, if you really want to thank us, -PHOTOS- of the set up when you are done. Bonus points for photos from Baja! We'd probably even reinstate your "man-card" if you did a magnetic mount AND won the Baja for your class.
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Old 12-16-2015, 12:16 PM
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As you become more interested in using a base-loaded 5/8 wave antenna rather than a 1/4 wave antenna, be sure to understand the full detail of what mmckenna meant when he wrote
"Someone who sticks to the 2 meter amateur frequencies and not need to transmit anywhere else or they live out on the plains might say a 5/8ths wave is "better"."
The average 5/8 wave VHF antenna is good for about 6 mHz of tuned, low VSWR bandwidth. So if you use an SWR meter and tune the 5/8 wave antenna for a center frequency of say, 145 mHz in the 2M ham band, that will give you great transmit SWR from about 142 - 148 mHz. As you can see, that is not within the operating range of the VHF licensed commercial freqs that have been discussed in this thread. The 5/8 wave will RECEIVE great throughout a very wide range of VHF freqs, but will only tune up for best transmit within that narrow 6 mHz span. Alternatively, you could set it for 152 mHz and get about 149-155 mHz transmit coverage... which is outside the 2M ham band. Unlike a 1/4 wave whip, you'll need to retune the 5/8 wave to optimize for your planned use. Think about that before you cut the whip... and if possible, use a 5/8 wave antenna that can be adjusted to your planned coverage.... or purchase additional steel whip elements, and change them accordingly for best SWR based upon your transmit freq.
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Old 12-16-2015, 12:17 PM
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Larsen makes a wideband 5/8th wave. It's only 2.5 dBd of gain instead of the full 3 dBd but it does cover 25 MHz of bandwidth. Model is NMO150-WB.
That particular antenna is a 1/2wave. Sinclabs, Maxrad and others also make wide band 1/2 wave antennas as well. I believe they all have optional springs available too. IMHO the Sinclab antenna is the best build quality of the three.

Quote:
Originally Posted by W5PKY View Post
I'm really fond of the Larsen NMO-Q line of 1/4 wave antennas. Add a spring and they are fairly rugged (had one on the XJ for 3 years without issue).

Agreed. A Larsen NMO-Q will last the longest, they are also pretty broad band as well. Bonus is, when cut for 146MHz, they are resonant 3/4 wave in the 70cm band as well.

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Is the higher the gain the better? Like is a 3db better then a 2.5db? Can you get an antenna for my situation that is higher than 3db gain?



Thanks,



Kix

You will never notice the difference between 2.5dB and 3dB of gain.

You can, find VHF antennas with higher gain but lose bandwidth. But will not really gain a whole lot of transmit/receive distance.

For VHF LMR you won't find anything though. What you will find is ham antennas. They are not that durable, and defiantly will not stand up to a Baja race.


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Old 12-16-2015, 12:30 PM
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Hey, if you really want to thank us, -PHOTOS- of the set up when you are done. Bonus points for photos from Baja! We'd probably even reinstate your "man-card" if you did a magnetic mount AND won the Baja for your class.
I will totally do that. I will permanently mount on my truck, but I might have to convince my buddy not to loose his man card. ;-) I will totally get some pics up. I'll take some pics of the big pro team set ups also. They pretty much have mobile base stations with Antennas on poles and sat radio and all kinds of other technology. Pretty impressive. Here is a link that some native out in the middle of the desert took of me when I took the handle bars during the 2014 B1K.

I had nothing to do with the music. lol https://www.youtube.com/watch?v=hZplMMUs3ig

You can get a little idea of some of the terrain I'll be dealing with. I will digest some of this and come back with some more questions. I'm probably going to go looking now and see what I can find. I'm assuming coax cable does not come with a lot of these antenna's so what's up with that?

1. Any particular type of coax better then another?

2. Does length matter?

3. will I have to buy connector also and splice myself?
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Old 12-16-2015, 12:36 PM
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For VHF LMR you won't find anything though. What you will find is ham antennas. They are not that durable, and defiantly will not stand up to a Baja race.
Wishing I knew how to highlight stuff, I'd highlight ^^ this ^^.

An "amateur" grade antenna is fine when cruising around with a magnetic mount in your wife's mini van going to the mall.
An "amateur" grade antenna is not suitable for public safety use. It's not suitable for any situation where life or property hang in the balance. It's certainly not suitable for the pure hell you are going to put it through in Baja.

You'll see professional grade antennas on police and fire vehicles for a very good reason. They've been proven to work over decades. When lives are on the line, you make sure you use the right gear and you use it properly. Cutting corners has no place in the land mobile radio industry, and it won't last long in Baja.
While I understand you'll be mostly on paved roads, I have been to Baja and their opinion of a "paved" road is very loosely interpreted.

You'll read a lot of posts on this site about people using amateur grade gear, or worse, low end Chinese stuff. They'll claim it works just fine and "works better", "talks farther" and is the "best" there is. I'll joyfully raise the B.S flag on these claims. Being low budget is OK. We've all been there. For an amateur radio operator "low budget" or "free" is a badge of honor. It's an excellent skill to have. Being able to make do with the minimum, or build your own is an honorable thing.
I wouldn't want to be doing that in Baja. There are several industries that use the Baja 1000 as a test bed for their technologies. They do this because it's the worst case scenario. Going cheap or half-assed on your communications isn't the way to do this. Don't cut corners for your race communications. It's OK to do that on the amateur side, but not when others lives can hang on the line.

You'll find that getting quality gear and installing it correctly is cheaper and easier in the long run. Having connections fall apart due to vibration will cost you time and energy in Baja. Might not be something you have a lot of down there. A high quality radio and antenna system is going to be cheaper for you in the long run.
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Old 12-16-2015, 12:44 PM
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Originally Posted by kixntuff View Post

1. Any particular type of coax better then another?
What comes with good quality NMO mounts will work fine.



Quote:
Originally Posted by kixntuff View Post
2. Does length matter?
Shorter is better. Do not coil up excess, cut it off. Keep the cable 12" or so longer than you need in case you need to re-terminate the connector.



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Originally Posted by kixntuff View Post
3. will I have to buy connector also and splice myself?

Most mounts will come with a connector. Make sure it is the mate to what ever is on the radio. Do not use adapters. Most kits will require the connector to be installed after running the cable. If you don't know how, get someone who does to install it.


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Old 12-16-2015, 12:44 PM
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Originally Posted by mmckenna View Post
Wishing I knew how to highlight stuff, I'd highlight ^^ this ^^.

An "amateur" grade antenna is fine when cruising around with a magnetic mount in your wife's mini van going to the mall.
An "amateur" grade antenna is not suitable for public safety use. It's not suitable for any situation where life or property hang in the balance. It's certainly not suitable for the pure hell you are going to put it through in Baja.

You'll see professional grade antennas on police and fire vehicles for a very good reason. They've been proven to work over decades. When lives are on the line, you make sure you use the right gear and you use it properly. Cutting corners has no place in the land mobile radio industry, and it won't last long in Baja.
While I understand you'll be mostly on paved roads, I have been to Baja and their opinion of a "paved" road is very loosely interpreted.

You'll read a lot of posts on this site about people using amateur grade gear, or worse, low end Chinese stuff. They'll claim it works just fine and "works better", "talks farther" and is the "best" there is. I'll joyfully raise the B.S flag on these claims. Being low budget is OK. We've all been there. For an amateur radio operator "low budget" or "free" is a badge of honor. It's an excellent skill to have. Being able to make do with the minimum, or build your own is an honorable thing.
I wouldn't want to be doing that in Baja. There are several industries that use the Baja 1000 as a test bed for their technologies. They do this because it's the worst case scenario. Going cheap or half-assed on your communications isn't the way to do this. Don't cut corners for your race communications. It's OK to do that on the amateur side, but not when others lives can hang on the line.

You'll find that getting quality gear and installing it correctly is cheaper and easier in the long run. Having connections fall apart due to vibration will cost you time and energy in Baja. Might not be something you have a lot of down there. A high quality radio and antenna system is going to be cheaper for you in the long run.

Well said. Cutting corners will cost more in the end every single time.


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Old 12-16-2015, 2:06 PM
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So what are you thoughts on this combo? DId I do good? Haven't purchased yet, just practicing.

Antenna - http://www.theantennafarm.com/catalo...o150c-738.html Should I get a spring for extra 15 bucks? I opted for 5/8ths wave because I will get a 2nd antenna for amateur band around the house.

Base magnetic mounts- http://www.theantennafarm.com/catalo...ic-mounts-265/
I'll be honest, I got lost right here and didn't even try. I got hung up on "N" Male, BNC Male, SMA , TNC, FME,

Am I correct in assuming that I will have to cut my antenna to operate per the instructions that will come with it to operate in the 151Mhz to 154Mhz even though it says 144-174Mhz (tunable)?
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Old 12-16-2015, 2:47 PM
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Quote:
Originally Posted by kixntuff View Post
So what are you thoughts on this combo? DId I do good? Haven't purchased yet, just practicing.

Antenna - http://www.theantennafarm.com/catalo...o150c-738.html Should I get a spring for extra 15 bucks? I opted for 5/8ths wave because I will get a 2nd antenna for amateur band around the house.

Base magnetic mounts- http://www.theantennafarm.com/catalo...ic-mounts-265/
I'll be honest, I got lost right here and didn't even try. I got hung up on "N" Male, BNC Male, SMA , TNC, FME,

Am I correct in assuming that I will have to cut my antenna to operate per the instructions that will come with it to operate in the 151Mhz to 154Mhz even though it says 144-174Mhz (tunable)?
Correct on the cut-to-length part. (There will be included instructions).

Currently, not a lot of VHF stuff uses N male. (Simoco and maybe Hytera). Mini-U is what is commonly found on Motorola mobile radios. UHF is what Icom, Kenwood and others love to use on VHF radios. BNC is found on older handheld radios commonly. SMA is what most hand held radios are shipping with (Motorola MURS/consumer grade radios may be using the older MX connector which would require a MX to BNC adapter) these days (I can't speak for the Kenwood TK series, Icom generally uses their proprietary take on the Motorola MX connector). TNC was common on GE 800 MHz radios but I haven't seen the back of the newer Harris stuff to know if it is present.

Personal preference, I don't run springs on 48" whips because I generally use 1/4 wave roof mounts. Now, hit something (like a tree branch) going fast enough with the whip, it'll fold over regardless (usually permanently).
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