Antenna Recommendations

[prcguy]

Most dual band and gain type antennas cut for the amateur band will not tune or work very well on GMRS, its just a little too far away in frequency. One of the few exceptions is a 6" quarter wave whip which will tune fine across the 440 to 467MHz range but its very low in performance.

Comet has a dual band model that claims wide band to cover amateur and commercial/GMRS freqs but some have reported its performance is below expected. I've run Larsen and Comet antennas for many years and Comet is not all that bad. Most Larsen antennas will last a bit longer but you will probably move on to something different well before a Comet fails.

 

[popnokick]

Back to your indoor "base" antenna situation... Something you may want to consider is a small beam / Yagi antenna. It is much less likely to be "...Keying up your radio and setting off the fire alarm/smoke alarms, screwing up the TV's in the building, etc" because its RF energy is directed out the upstairs window rather than sprayed around in an omnidirectional pattern all over the inside of the building. HOWEVER, it will also transmit / receive very well but primarily in the direction the window faces. In addition, it will be very narrow bandwidth. You will find dual-band beams, but GMRS on the same antenna will be a challenge. If you're space constrained, UHF-only beams are smallest due to the shorter wavelength. Of course it will be useful to use the window that faces the most repeaters or other stations you want to reach.

 

[tadpole207]

Yes. Definitely want something that will work out if the box, as I don’t have any tuning instruments yet. Much appreciated.

I think the links you sent are to the same Larsen antenna. Is there another for the bands plus GMRS?

I think I’ll go nmo on the jeep. That way I can try different antennas out with the same mount and cable.
So right now I have 2 options if I remove the field tunable antenna.

if the link you send over is to another, I will have 3.

Comet: COMET-NCG SBB-1NMO Antenna Mobile Dual Band 2m-70cm, SBB1NMO

Larsen: Larsen NMO2/70B

These are exciting times my friends.

 

[popnokick]

Forgot to mention: My SBB-1NMO wasn't perfect on GMRS but quite usable for that.

 

[tadpole207]

Forgot to mention: My SBB-1NMO wasn't perfect on GMRS but quite usable for that.

thanks. So I’m guessing that the 2 and 70 can reach GMRS (I can RX perfectly on my UV5r and tx perfectly on the Wouxun) to the 2 repeaters I was able to linkup with once I got Chirp down pat. What is the technical reason 2 and 70 can do “alright” on GMRS but not perfectly? Is it physically possible to have 1 antenna that can do all 3?

I know you said to watch out for the gimmicks with that one antenna with 2 whips on it. I would imagine the best solution is to mount 2 antennas on the jeep- one for 2 and 70 and the other for GMRS- but would that mean I have to switch often?

Is there something that would allow the radio to be tied onto 2antennas at once?
What would be the “best” option for 1 antenna at the moment? The Larsen, comet or something else?

 

[mmckenna]

Yes. Definitely want something that will work out if the box, as I don’t have any tuning instruments yet. Much appreciated.

I think the links you sent are to the same Larsen antenna. Is there another for the bands plus GMRS?

You are correct, I linked to the same one twice.
This is the one I meant to link:

Larsen NMO150/450/758 Mobile Antenna Tri-Band 150-165,450-470,700/800MHz

Tri-band antenna covers 150-174, 430-520 & 750-870, 100 Watts, Whip Length 16.5"

theantennafarm.com

I purchased that antenna last year and did a write up on it:

Larsen Multi-Band antennas

I ordered two Larsen multi-band antennas recently to try out for a project at work. NMO-150/450/758SF NMO-150/450/800SF I brought them home from work along with my Agilent spectrum analyzer with tracking generator so I could sweep them on my truck. Antenna mount is a Larsen NMO-HF installed...

forums.radioreference.com

While not designed to be a ham radio antenna, it will perform just fine there. It was running about 1.8:1 SWR on the 2 meter band,

I think I’ll go nmo on the jeep. That way I can try different antennas out with the same mount and cable.
So right now I have 2 options if I remove the field tunable antenna.

Wait.

What KIND of Jeep vehicle, specifically?

Comet: COMET-NCG SBB-1NMO Antenna Mobile Dual Band 2m-70cm, SBB1NMO

Years ago my dad had one of those on his truck. It's a bit shorter than 1/4 wave on VHF, so I think it's got a helically wound section to help on UHF. It worked as well as the standard 1/4 wave VHF antenna he replaced it with. Never tried to sweep it to see what it looked like outside the ham bands.

Larsen: Larsen NMO2/70B

As PRCGUY pointed out, that antenna isn't going to do you any favors outside the ham bands. It's designed for 2 meters and 70 centimeters only. Probably not going to work well on GMRS.

The NMO-2/70SH is the shortened version. It's 1/4 wave on VHF, about 19 inches tall. I have swept that antenna for the full VHF and UHF bands, and it'll give you halfway decent SWR on GMRS.
But, band specific antennas are going to be better.

 

[tadpole207]

2017 JK

 

[mmckenna]

thanks. So I’m guessing that the 2 and 70 can reach GMRS (I can RX perfectly on my UV5r and tx perfectly on the Wouxun) to the 2 repeaters I was able to linkup with once I got Chirp down pat. What is the technical reason 2 and 70 can do “alright” on GMRS but not perfectly? Is it physically possible to have 1 antenna that can do all 3?

Antennas only have so much usable bandwidth. That is, the antenna only provides a low SWR (radiates the energy well) on specific parts of the band. Most of these ham antennas are designed to work well in the 430-450MHz range, where the 70cm band is. GMRS is up at 462/467MHz, which is well away from 70cm.
The antenna needs to be resonate at the bands you want to use it on. You have some leeway, and the amount of leeway (bandwidth) will depend on the exact design of the antenna. Usually when you design an antenna for more bandwidth, the performance/gain drops off quickly. If you want better performance/gain, the bandwidth drops off quickly. Finding the sweet spot can be a challenge, especially in mobile environments and with widely spaced frequencies, like 70cm and GMRS.

I know you said to watch out for the gimmicks with that one antenna with 2 whips on it. I would imagine the best solution is to mount 2 antennas on the jeep- one for 2 and 70 and the other for GMRS- but would that mean I have to switch often?

Is there something that would allow the radio to be tied onto 2antennas at once?
What would be the “best” option for 1 antenna at the moment? The Larsen, comet or something else?

Band specific antennas are best since they are optimized for the bands you want to use them on.
It's not just low SWR you are looking for, it's also the radiation pattern. That is, where the antenna focuses the energy. You want that energy to go in the direction of the other station you want to talk to (or the repeater).

If you used one radio for 2 meters, 70cm and GMRS, and you wanted to run a dual band antenna for ham, and a dedicated GMRS antenna, you'd need to switch between the antennas when you wanted to transmit.

There are diplexers that will split antenna ports by frequency, but getting one that will split 70cm from GMRS and do it well would be expensive, as in "cheaper to buy a dedicated GMRS radio" expensive.

So, "best" antenna?

Yeah, ask 10 different people and you'll get at least 11 different opinions. You have some good options above. Which one you decide to go with will depend on which compromises you want to make. No one can really answer that for you.

 

[mmckenna]

2017 JK

Ouch.

OK, it can be done, but getting a ground plane under the antenna on a Jeep like that can be a challenge. I think @prcguy is your best resource there. I know he has a Jeep product and can probably give you some sound advice.

 

[mmckenna]

You may want to start a separate post about antenna mountings on Jeeps. That's a whole 'nuther ball of wax you'll have to deal with. There are some posts on here about guys doing really nice setups on Jeep Wranglers and JK's, but good installs are few and far between. It take some serious work to do it right. One guy in particular did a radio for 2 meter/70 centimeter and a separate GMRS radio. That way he could have dedicated antennas that worked best in that particular install.

 

[mmckenna]

Here ya go. Read this thread in it's entirety:

Multiple Antenna Question for 2M/70CM

I am looking at installing an ICOM IC-2730A mobile radio for 2M/70cm in my Jeep for off-road communications. I currently have both a Midland GRMS radio (MXT400) and an older Cobra CB. The MXT400 is connected to a Midland MXTA11 6db gain antenna which is mounted to my rear tire carrier and near...

forums.radioreference.com

 

[prcguy]

The best place I've found on a Jeep for VHF/UHF antennas is an NMO mount on the hood near the hood hinges. That gives you a reasonable ground plane and its very easy to route the coax into the cab on the passenger side. That part of the hood has a slight slope towards the side and front of the vehicle so really long antennas will need a slight tweak to make them perfectly vertical. A 1/4 wave VHF or UHF whip is fine without tweaking.

A lot of people seem to be using a mount that sticks out the side of the vehicle along the lower cowl even with the bottom edge of the hood. That's a good 6" below the top of the hood and many antennas do not work well there and I would avoid that. Here is a big Larson NMO 2/70B dual band amateur antenna on an NMO trunk lip/hood mount on a JT with the slight tweak at the base.

Oh look, you can see a reflection of my 133ft OCFD HF antenna going across the front windshield. How nice.

Ouch.

OK, it can be done, but getting a ground plane under the antenna on a Jeep like that can be a challenge. I think @prcguy is your best resource there. I know he has a Jeep product and can probably give you some sound advice.

 

[tadpole207]

Wow. I did t even think putting 2 antennas next to each other would damage themselves and the receiver.

Would a mag mount on a jeep be enough ground plane?

it seems that works unless I install NMO onto fender (maybe driver side opposite of the radio antenna)

I understand mag mounts can look crappy, but I will at least install the wiring “professionally”.
As my understanding is, Jeeps don’t offer a great ground plane unless it’s magnetic.

How is this one?

Diamond MR75S Dual Band 144/440MHz 2m/70cm Magnet Mt Amateur Ham Radio Antenna

VHF/UHF 2m/70cm Dual band Mobile Antenna, Adjustable Mount, 9'10" LMR 100 w/ SMA male connector

theantennafarm.com

one more to confirm what you think the connector I need is- the Anytone is SO-239. Is that male or female? What connection does the antenna cable need to be?

 

[Solidjake]

For amateur radio I have the 2/70. Amazing antenna...

 

[tadpole207]

Another one closer to 2,70 and GMRS

Comet CA-2x4SRNMO Dual Band 140-160/435-465 MHz VHF/UHF Mobile Antenna W/ Fold

VHF/UHF 140-160/435-465 MHz Mobile Antenna W/ Fold-over hinge NMO Type Mount

theantennafarm.com

 

[prcguy]

A ground plane for an antenna does not have to be magnetic, anything conductive like steel or aluminum or brass, etc, will work fine. The hood on a Jeep is plenty large enough for a VHF/UHF ground plane and will probably be ok at CB frequencies.

Wow. I did t even think putting 2 antennas next to each other would damage themselves and the receiver.

Would a mag mount on a jeep be enough ground plane?

it seems that works unless I install NMO onto fender (maybe driver side opposite of the radio antenna)

I understand mag mounts can look crappy, but I will at least install the wiring “professionally”.
As my understanding is, Jeeps don’t offer a great ground plane unless it’s magnetic.

How is this one?

Diamond MR75S Dual Band 144/440MHz 2m/70cm Magnet Mt Amateur Ham Radio Antenna

VHF/UHF 2m/70cm Dual band Mobile Antenna, Adjustable Mount, 9'10" LMR 100 w/ SMA male connector

theantennafarm.com

one more to confirm what you think the connector I need is- the Anytone is SO-239. Is that male or female? What connection does the antenna cable need to be?

 

[mmckenna]

one more to confirm what you think the connector I need is- the Anytone is SO-239. Is that male or female? What connection does the antenna cable need to be?

SO-239 is the part number for the UHF SOcket. <—female persuasion.
PL-259 is the part number for the UHF PLug. <— male persuasion.

You want your antenna mount to have a PL-259/Male UHF connector on the end to connect to your radio. You may also see on some Japanese products the UHF connector referred to as a Type-M connector, not to be confused with the Type-N connector.

The mag mount I linked to above is the right one for your radio.

Avoid the temptation to use adapters...

 

[alcahuete]

The NMO-150/450/800SF that @mmckenna mentioned above, is a fantastic all-around antenna, with good gain on UHF. I just bought a few of them about a month ago, and have been incredibly impressed. It's only 16.5" long with a spring, so for an extra 10" over the 1/4 wave UHF antenna I was previously using, you add VHF and 800-900 MHz. I use it on ham, GMRS, business band frequencies, and soon DTR radios, perhaps. As was mentioned, the SWR down in the 2m band is just fine.

I have never had any problems with the Larsen plastic bases, but this one is solid metal. Has a really nice and heavy feel to it, and will probably last forever. Are there better antennas out there from a performance perspective? Sure. But for an antenna that covers basically everything, in a really small package, it is fantastic.

 

[tadpole207]

@alcahuete just to confirm, you refer to this:

Larsen NMO150/450/758 Mobile Antenna Tri-Band 150-165,450-470,700/800MHz

Tri-band antenna covers 150-174, 430-520 & 750-870, 100 Watts, Whip Length 16.5"

theantennafarm.com

 

[tweiss3]

That is the one. I have that one, and the 2/70sh, which is about 1 inch longer. The 2/70sh works a bit better on 2 meters, but both work well on 70cm and GMRS. Of course, you SHOULD drill the hole in your car and permanent mount it. Both are ground plane dependent, and need a good permanent mount to work to their fullest.