best ⅝ wave GMRS high gain NMO antenna

[CyborgAlienWRYG738]

I'm not worried as much about cost as I am having the best long range NMO no ground plane GMRS antenna I can get, prefer at least ⅝ wave.

Nothing under 5db gain and it should also be able to do 2m. A plus if it can do: 136-180 VHF • 219-250 VHF • 350-512 UHF • 700-960 UHF quad-band, with GMRS being the necessity.

I've already wasted money on the Diamond and Tram junk, now I'm wanting the best. I'm using a magnet mount, as a necessity as well, albeit I'm open for a better model of it as well. I'm looking for at least 5" magnet for stability. Going on a leased Nissan Rogue, can't be permanent mount.

[CyborgAlienWRYG738]

35 minutes ago, WRZM228 said:

I have 2 choices.. Get an extra longer whip just like what the the other guy is suggesting. Its .100 of an inch obviously medium cast stainless steel family. 

Or I return this and get the B4505. which I think sounds better.

I used an old Wilson lil wil whip on one of my antennas for a replacement where I cut too short but, now I have to replace it... BTW they're about $25 to replace...

[CyborgAlienWRYG738]

34 minutes ago, WRZM228 said:

what about home base antenna?

I need something to use for both but, I'm looking for those too for future purchases... Just right now it's more important to have a portable one, comes in greater hand for bugouts, mobiles, home, etc.

[WRZM228]

2 minutes ago, CyborgAlienWRYG738 said:

I used an old Wilson lil wil whip on one of my antennas for a replacement where I cut too short but, now I have to replace it... BTW they're about $25 to replace...

I wanna buy the same one for emergency. Is it a one piece with magnamount?

 

[wayoverthere]

10 hours ago, kidphc said:

It is rough for us Hams because the 70cm and GMRS bands are to close to use a duplexer for separate antennas. But far enough apart that anything that cover both bands, that we either sacrifice part of each band, or have silly SWR at the ends of both bands. Personally, I shoot for about 450-453 Mhz, when tuning them to try to get the most bandwidth. Usually, start ending up with 1.67-1.75 on the band edges. Acceptable, for a really compromised antenna.

Easiest route is to go 1/4 wave for either band and usually will cover both bands with below 1.6 SWR. Lowest SWR will end up being in the commercial band.  But they are the broadest bandwith designs you will find. I don't use them because the roof rack shadows too much of the antenna, I end up with worse performance then with a 5/8 wave and coil design.

The one antenna I've found that actually did well on both was a Browning (br1713bs, 2x5/8 wave), rated for 410-490mhz, iirc. When testing, both on 70cm and gmrs, I never saw higher than 1.2:1. I never tested it without SOME ground plane, but to be fair, my little truck isn't a ton of space either (center roof, single cab compact truck). Unfortunately, some poking around looks like it may be limited availability or discontinued.

Tram does also have a 1/4 wave they rate for a similar frequency range, though I haven't used it, so I don't know the model number offhand.

[WRZM228]

On 11/16/2023 at 11:24 AM, CyborgAlienWRYG738 said:

I'm not worried as much about cost as I am having the best long range NMO no ground plane GMRS antenna I can get, prefer at least ⅝ wave.

Nothing under 5db gain and it should also be able to do 2m. A plus if it can do: 136-180 VHF • 219-250 VHF • 350-512 UHF • 700-960 UHF quad-band, with GMRS being the necessity.

I've already wasted money on the Diamond and Tram junk, now I'm wanting the best. I'm using a magnet mount, as a necessity as well, albeit I'm open for a better model of it as well. I'm looking for at least 5" magnet for stability. Going on a leased Nissan Rogue, can't be permanent mount.

I think I'm gonna grab this one. They said its easier to tune and it kicks the GMRS repeater like an old fashion alarm clock. There are just 2 nit picks I would like to change if there is a factory option. I don't like the color of the whip and I wish it was chrome or stainless. The 2nd one is the in between coil or extender. Its bad enough it has a spring on the bottom. I hope Laird has an exact match performance in chrome and minimalist whip. If not, its fine.. I'll get it. I'm gonna double check with them if I can use the magna-mount I got from them. It fits like a glove fir my needs. The magnet is really strong, the cable is LMR-195, The connector feels like pro-am, the bottom is rubberized and the connection is brass that fits right on with the Laird whip with the o-ring seal. I hope I get this straighten out today.

BTW: I bought an okay mobile radio (AnyTone AT-7xxUV)  so I wont have to mess with my other radio and just leave as a base station. It would have been nice if I have the mobile antenna running. But will wait then.

[CyborgAlienWRYG738]

3 hours ago, WRZM228 said:

I think I'm gonna grab this one. They said its easier to tune and it kicks the GMRS repeater like an old fashion alarm clock. There are just 2 nit picks I would like to change if there is a factory option. I don't like the color of the whip and I wish it was chrome or stainless. The 2nd one is the in between coil or extender. Its bad enough it has a spring on the bottom. I hope Laird has an exact match performance in chrome and minimalist whip. If not, its fine.. I'll get it. I'm gonna double check with them if I can use the magna-mount I got from them. It fits like a glove fir my needs. The magnet is really strong, the cable is LMR-195, The connector feels like pro-am, the bottom is rubberized and the connection is brass that fits right on with the Laird whip with the o-ring seal. I hope I get this straighten out today.

BTW: I bought an okay mobile radio (AnyTone AT-7xxUV)  so I wont have to mess with my other radio and just leave as a base station. It would have been nice if I have the mobile antenna running. But will wait then.

Get the B4505CN the extra "B" means it's black, that one is chrome. The trailing "S" means spring. I'm going to have to wait for the first of the year., to spend anymore money, my next orders going to also include a mobile radio once I decide which one to get.

Looking at the Anytone AT-D578UVIII Plus Triple/Dual Band, (interchangeable with codes),or the TYT MD-9600, or something similar. I have yet to make up my mind. Mostly from lack of input on which units are better. Those even have superheterodynes in them. Well the TYT does, not completely sure about the Anytone. 

Any suggestions? I've been looking at other brands as well but, those two seem to be the easiest to get to do what I want. I hope to find something not made in China but, that seems impossible at this point.

[WRZM228]

On 12/2/2023 at 7:19 AM, CyborgAlienWRYG738 said:

Get the B4505CN the extra "B" means it's black, that one is chrome. The trailing "S" means spring. I'm going to have to wait for the first of the year., to spend anymore money, my next orders going to also include a mobile radio once I decide which one to get.

Looking at the Anytone AT-D578UVIII Plus Triple/Dual Band, (interchangeable with codes),or the TYT MD-9600, or something similar. I have yet to make up my mind. Mostly from lack of input on which units are better. Those even have superheterodynes in them. Well the TYT does, not completely sure about the Anytone. 

Any suggestions? I've been looking at other brands as well but, those two seem to be the easiest to get to do what I want. I hope to find something not made in China but, that seems impossible at this point.

Oh cool! I can use that info. Its its exactly the same specs, that's what I want. So that lower spring is just to relieve the tension when driving? The height is not that bad for I prefer short as long as it  not live 40 or over.

The lower Anytone like the one I bought is a radio in "okay to good" category. I don't know much about GMRS especially the higher caliber radio. But If I was going to pick a CB radio above $250, that is a solid mobile/base, I will pick the "Better to Best" for me like an original Cobra 148 GTL and correctly dialed, or President Lincoln. (BTW: If President will come up with GMRS, 100% I'll buy one anytime) Anyways as what I know in the equivalent of that radio on which I only need dual band: The other thing I wish I can adopt is a separate mic. I donbt like teh idea of having a mic with the controller in it and an RJ-45 socket. If I still have my old radio technician, he would easily do all these for me. On my CB days, He worked on my old cobra radio. I had a superstar 360 and Ranger X9 which is  highly sophisticated radio than the cobra. I used all of them for 5 years. I'd pick the 148 GTL than any of the 2. Sometimes its not just features. If you have a good carrier with 40% modulation is just okay. But if I have  100% or more modulation and swinging 1 to 4 db, I'd rather have that. That was the magic of the old cobras that's why they were really popular... at that time! 

[CyborgAlienWRYG738]

3 minutes ago, WRZM228 said:

Oh cool! I can use that info. Its its exactly the same specs, that's what I want. So that lower spring is just to relieve the tension when driving? The height is not that bad for I prefer short as long as it  not live 40 or over.

The lower Anytone like the one I bought is a radio in "okay to good" category. I don't know much about GMRS especially the higher caliber radio. But If I was going to pick a CB radio above $250, that is a solid mobile/base, I will pick the "Better to Best" for me like an original Cobra 148 GTL and correctly dialed, or President Lincoln. (BTW: If President will come up with GMRS, 100% I'll buy one anytime) Anyways as what I know in the equivalent of that radio on which I only need dual band:

Icom 2730A
Yaesu 6000R
Alinco 735T

I'm a bit biased for I like the looks and all Japanese design and and parts. I picked the 735T. But honestly all those 3 are really good. 

I'm stuck on my Unidens but, I have used most of the others, I just prefer my 520XL Pro as far as CBs go.

I've looked at those 3 and I've considered them, I'm just looking forward to if/when I get my Technician license, (I'm wanting it to do digital mostly,) I'm wanting to go ahead and get a DMR radio so I don't have to buy another one later. Otherwise I would've just went with one of the above. I'm leaning towards the Alinco but, the Icom 2730a has my eye as well.

[WRZM228]

39 minutes ago, CyborgAlienWRYG738 said:

I'm stuck on my Unidens but, I have used most of the others, I just prefer my 520XL Pro as far as CBs go.

I've looked at those 3 and I've considered them, I'm just looking forward to if/when I get my Technician license, (I'm wanting it to do digital mostly,) I'm wanting to go ahead and get a DMR radio so I don't have to buy another one later. Otherwise I would've just went with one of the above. I'm leaning towards the Alinco but, the Icom 2730a has my eye as well.

I was watching Randy on Youtube. He knows and owns lots of radios.. I wanna ask him  few things about setting up om repeater

[WRYZ926]

Quite a few guys in my local club run the Icom 2730A and they really like them. I have no experience with the TYT MD-9600 but I have very pleased with the TYT TH-7800 dual band mobile. I was talking to my brother on 70CM simplex yesterday at 18 miles away. He was at home on his base station and I was in my car using the TH-7800 with a 16" Comet SBB1 NMO antenna.

[WRZM228]

4 hours ago, CyborgAlienWRYG738 said:

Get the B4505CN the extra "B" means it's black, that one is chrome. The trailing "S" means spring. I'm going to have to wait for the first of the year., to spend anymore money, my next orders going to also include a mobile radio once I decide which one to get.

Looking at the Anytone AT-D578UVIII Plus Triple/Dual Band, (interchangeable with codes),or the TYT MD-9600, or something similar. I have yet to make up my mind. Mostly from lack of input on which units are better. Those even have superheterodynes in them. Well the TYT does, not completely sure about the Anytone. 

Any suggestions? I've been looking at other brands as well but, those two seem to be the easiest to get to do what I want. I hope to find something not made in China but, that seems impossible at this point.

Do you know where and what chrp software they use on AnyTone AT-778UV?

[CyborgAlienWRYG738]

5 hours ago, WRZM228 said:

I was watching Randy on Youtube. He knows and owns lots of radios.. I wanna ask him  few things about setting up om repeater

He has videos on it in his YouTube channel 

[CyborgAlienWRYG738]

4 hours ago, WRZM228 said:

Do you know where and what chrp software they use on AnyTone AT-778UV?

I'm not sure if it's on Chirp or not, if so it would be on ChirpNext, they've pretty much abandoned the original Chirp, from what I understand.

 

Chirp Home 

ChirpNext Downloads

Chirp Linux Instructions

[CyborgAlienWRYG738]

6 hours ago, CyborgAlienWRYG738 said:

I'm stuck on my Unidens but, I have used most of the others, I just prefer my 520XL Pro as far as CBs go.

I've looked at those 3 and I've considered them, I'm just looking forward to if/when I get my Technician license, (I'm wanting it to do digital mostly,) I'm wanting to go ahead and get a DMR radio so I don't have to buy another one later. Otherwise I would've just went with one of the above. I'm leaning towards the Alinco but, the Icom 2730a has my eye as well.

Speaking of CB, I just come across my old Cobra 29LTD Chrome that I used in my pickup a while back. I need to take it in and make sure it's ok and still in tune.

[CyborgAlienWRYG738]

7 hours ago, WRZM228 said:

 

The other thing I wish I can adopt is a separate mic. I donbt like teh idea of having a mic with the controller in it and an RJ-45 socket. If I still have my old radio technician, he would easily do all these for me. On my CB days, He worked on my old cobra radio. I had a superstar 360 and Ranger X9 which is  highly sophisticated radio than the cobra. I used all of them for 5 years. I'd pick the 148 GTL than any of the 2. Sometimes its not just features. If you have a good carrier with 40% modulation is just okay. But if I have  100% or more modulation and swinging 1 to 4 db, I'd rather have that. That was the magic of the old cobras that's why they were really popular... at that time! 

I like the Astatic mikes best too. Especially that particular model. I'm not all that crazy about the Mikes with buttons all over them, the ONLY thing should be on the Mics is a PTT and maybe a gain or squelch control but, nothing more, IMHO.

[WRZM228]

21 minutes ago, CyborgAlienWRYG738 said:

Speaking of CB, I just come across my old Cobra 29LTD Chrome that I used in my pickup a while back. I need to take it in and make sure it's ok and still in tune.

Those old school 29 LTD are really good in modulation. I know someone he was using if for a home base in Long beach just using a fire stick  (or Big Stick for home). I couldn't believe I can hear him all the way pass Pico Rivera. Its good to have the old cobra as a backup emergency. 

 

 

 

 

 

 

 

 

 

 

[CyborgAlienWRYG738]

28 minutes ago, WRZM228 said:

Those old school 29 LTD are really good in modulation. I know someone he was using if for a home base in Long beach just using a fire stick  (or Big Stick for home). I couldn't believe I can hear him all the way pass Pico Rivera. Its good to have the old cobra as a backup emergency. 

 

 

 

 

 

 

 

 

 

 

I want to get this one checked out and make sure it's still in tune and the finals are ok. It's already been setup for linear, (I like the sound better when they're setup correctly,) I miss my old Cobra 29 and 25 from back in the 70's. The 29 disappeared but, I did have the 25 floating around somewhere. I also had a Uniden 6? and 76 but, I sold them. (They were both made in the USA.) I'm kicking myself for not keeping them, they were perfectly tuned and I have talked from Tampa Florida to the docks at the Dallas shipyard on the 76 with no ground antennas from Wilson when they still made them. I'm missing one of them now but, I still have the one I'm using with my 520XL Pro.

[WRZM228]

1 hour ago, CyborgAlienWRYG738 said:

I want to get this one checked out and make sure it's still in tune and the finals are ok. It's already been setup for linear, (I like the sound better when they're setup correctly,) I miss my old Cobra 29 and 25 from back in the 70's. The 29 disappeared but, I did have the 25 floating around somewhere. I also had a Uniden 6? and 76 but, I sold them. (They were both made in the USA.) I'm kicking myself for not keeping them, they were perfectly tuned and I have talked from Tampa Florida to the docks at the Dallas shipyard on the 76 with no ground antennas from Wilson when they still made them. I'm missing one of them now but, I still have the one I'm using with my 520XL Pro.

That looks like a nice limited edition. Never seen one. Ive seen lots of people advertising they'll do a full recap on the radio. Or if you want, I know a real good 10-11-12 meter (cb included) radio that will really blow your mind. It has everything for less than 200 bucks. 

By the way.. if you ever watch one of this guys video, it'll take you back and youll get hooked. This guy is using a regular old school cb radio like yours and he can hit almost any part of the world with no repeater, under 40 watts and he make all kinds of home antenna for a few bucks...  15:39

 

[SpeedSpeak2Me]

20 hours ago, WRZM228 said:

I think I'm gonna grab this one. They said its easier to tune and it kicks the GMRS repeater like an old fashion alarm clock. There are just 2 nit picks I would like to change if there is a factory option. I don't like the color of the whip and I wish it was chrome or stainless. The 2nd one is the in between coil or extender. Its bad enough it has a spring on the bottom. I hope Laird has an exact match performance in chrome and minimalist whip. If not, its fine.. I'll get it. I'm gonna double check with them if I can use the magna-mount I got from them. It fits like a glove fir my needs. The magnet is really strong, the cable is LMR-195, The connector feels like pro-am, the bottom is rubberized and the connection is brass that fits right on with the Laird whip with the o-ring seal. I hope I get this straighten out today.

BTW: I bought an okay mobile radio (AnyTone AT-7xxUV)  so I wont have to mess with my other radio and just leave as a base station. It would have been nice if I have the mobile antenna running. But will wait then.

I have one of these, without the spring, so the BB4505CN.  IIRC, they make two "spring" versions.  One has a steel spring, the BB4505CNS/B4505CNS, and one with an elastomer spring BB4505CNS(R)/B4505CNS(R).  The springs are not-so-much for wind loading, but in case you hit something with it, like a garage door header or tree branches.

I intentionally got the "no ground plane required" version for a car that has very little area for the ground plane.  The antenna works great, since the bottom half serves as the ground plane, with the signal propagating from the top half above the coil.

The trimming chart on the package is accurate, and I've found that my final trimmed length is usually within 0.0625" (1/16th) to 0.125" (1/8th) listed on the chart (typically longer).  That is with 12' of RG8X on a mag mount, and using a RigExpert Stick Pro (antenna analyzer).  I have mine cut to favor repeater inputs rather than simplex, since that is where it is used most.  In reality I could have aimed for center-band and would never notice a difference.

My SWRs are 1.5:1 or less from 457 MHz up to 478 MHz, the lowest being 1.06:1 @ 465.6000 MHz

 

The Return Loss chart shows a more accurate reading of the tuning:

 

For this vehicle I also have the BB4502N, which is also a very good performer for its length (~ 10"), but it is 1/2λ, not 5/8λ.  Additionally I have the BB4503 (5/8λ) and the BB4505C for another vehicle which does have sufficient area for the ground plane, and those also have excellent performance.

In the event that you (or others) are curious, here is a direct comparison of the BB4505CN to the BB4505C, covering a 30 MHz bandwidth.  Green line is the BB4505CN, and the orange line is the BB4505C.

Some people say I like Laird antennas, and they would be correct.

[CyborgAlienWRYG738]

50 minutes ago, SpeedSpeak2Me said:

I have one of these, without the spring, so the BB4505CN.  IIRC, they make two "spring" versions.  One has a steel spring, the BB4505CNS/B4505CNS, and one with an elastomer spring BB4505CNS(R)/B4505CNS(R).  The springs are not-so-much for wind loading, but in case you hit something with it, like a garage door header or tree branches.

I intentionally got the "no ground plane required" version for a car that has very little area for the ground plane.  The antenna works great, since the bottom half serves as the ground plane, with the signal propagating from the top half above the coil.

The trimming chart on the package is accurate, and I've found that my final trimmed length is usually within 0.0625" (1/16th) to 0.125" (1/8th) listed on the chart (typically longer).  That is with 12' of RG8X on a mag mount, and using a RigExpert Stick Pro (antenna analyzer).  I have mine cut to favor repeater inputs rather than simplex, since that is where it is used most.  In reality I could have aimed for center-band and would never notice a difference.

My SWRs are 1.5:1 or less from 457 MHz up to 478 MHz, the lowest being 1.06:1 @ 465.6000 MHz

 

The Return Loss chart shows a more accurate reading of the tuning:

 

For this vehicle I also have the BB4502N, which is also a very good performer for its length (~ 10"), but it is 1/2λ, not 5/8λ.  Additionally I have the BB4503 (5/8λ) and the BB4505C for another vehicle which does have sufficient area for the ground plane, and those also have excellent performance.

In the event that you (or others) are curious, here is a direct comparison of the BB4505CN to the BB4505C, covering a 30 MHz bandwidth.  Green line is the BB4505CN, and the orange line is the BB4505C.

Some people say I like Laird antennas, and they would be correct.

Much thanks for the excellent info. I wish I had this information before I went and purchased all the junk I thought was decent and wasted all my money on them other brands. As soon as I can find the money again, I will be getting one of these B4505CN antenna. I read that for GMRS you want to have RG58A/U cable off the base, in a 5" NMO magnet mount I'm having difficulty finding any that include that cable, most are 3" and with a 3' antenna I'm not sure if that's going to be sufficient or not. The one I have found is from Tram, the Chrome mount, is supposed to have it but, the one I got, doesn't. It's just RG58/U. Which is better for 70cm and 2m. 

[SpeedSpeak2Me]

1 hour ago, CyborgAlienWRYG738 said:

Much thanks for the excellent info. I wish I had this information before I went and purchased all the junk I thought was decent and wasted all my money on them other brands. As soon as I can find the money again, I will be getting one of these B4505CN antenna. I read that for GMRS you want to have RG58A/U cable off the base, in a 5" NMO magnet mount I'm having difficulty finding any that include that cable, most are 3" and with a 3' antenna I'm not sure if that's going to be sufficient or not. The one I have found is from Tram, the Chrome mount, is supposed to have it but, the one I got, doesn't. It's just RG58/U. Which is better for 70cm and 2m. 

You're quite welcome for the information, and don't feel bad.  When I first got into GMRS I picked up one of the Nagoya UT-72G antennas based on other people's recommendations.  I got two from two different resellers and they were both junk.  The SWRs for simplex were 1.77:1, and at the repeater inputs it was almost 2.10:1.  Some will say anything under 2:1  is okay, but i just wasn't comfortable using something that was that far off, when I knew there was better.  I did have people tell me I got the wrong antenna, that I got the UT-72 (2m/70cm) by ignorance.  However I have that antenna as well, so I had a direct comparison (at the end of this post).  The UT-72 performs slightly better than the UT-72G on GMRS.

Having invested in the quality equipment (the RigExpert), it really lets me know exactly what is going on.  I did my testing on three different vehicles, all with more than enough area for a ground plane, and got the same results for both antennas (UT-72G) on all three vehicles.  Where some initial mistakes were made was using an inexpensive inline SWR meter, the Surecom SW102.  It's good for confirming your TX frequency and power (when used with a 50Ω dummy load), and that's about all I trust it for.  Others have had measured success with them, but when compared to a quality antenna analyzer, they just don't hold up.  At least that is what I have found with my use of them, YMMV.

I use 3.25" bases with both of my 32" antennas and have no issues, even at highway speeds.  You have to be careful with the base size, as I have found that too large of a magnetic base will impact your tuning.  For example I helped a person that purchased a 6" mag mount, and from experience I could tell before we did any trimming of his Laird BB4503 that something was wrong. The SWR's were way too high, and the "shape" (peaks/valleys) were in the wrong places.  We switched them to a 3.25" base and the antenna went to where it should have been.

The reason is, I believe, and more knowledgeable persons on here can correct me if I am wrong, is that due to the requirement of needing at least 1/4 wavelength ground plane (about 6.3" / 16cm), the diameter of the base was interfering with the ground plane itself.

For reference, this is the mag mount that I use, which has 12' of RG8X, and is paired with the BB4505CN or BB4502N.
Laird TE Connectivity GB8X

I also have this base with 12' of RG58/U, with the removable rubber boot, and pair it with the BB4505C or the BB4503.
Laird TE Connectivity GBR8PI

The GB8PI is the same as the GBR8PI, but without the rubber boot. So you're basically being charged $7-8 for the boot, which isn't required, nor does it hurt its performance.

Now, I do say "as a reference" because The Antenna Farm is closed until Summer of 2024, but they are still an excellent resource.  An alternative mount, which I have yet to hear anything negative about is the Midland MXTA12 mag mount.  It is also more readily available, and is 3.5" in diameter.  To go further with that, Midland's MXTA26 GMRS NMO antenna is also an excellent performer, and requires no tuning.  These two items are very often paired with each other.

I have Midland's MXTA13 mag mount, which is a 1/4λ, with a 1" magnet, 6" mast, and 20' of spaghetti (RG-174) for coax.  It performs better than I ever would have given it credit for, even with the massive amount of attenuation from the coax, which is about 20dB per 100', which is a lot.  However it works in a pinch for temporary use, and over flat terrain I can hit repeaters 30 miles away with just 15w.

As mentioned above (both antennas on the same vehicle, positioned in the same place).  Sweep is 400-500 MHz.
Red - Nagoya UT-72G
Blue - Nagoya UT-72

[WRZM228]

Thank you for the followup and information. I'll be getting the B4505CN chrome whip. It should be easier to tune and match that antenna too and hopefully they'll recommend me to keep this magnamount. I really like it and quite strong and 1/3 of a size of a K40 Magnamount. Its got a rubber feet, 12 ft LMR-195 cable and high grade connector. Th lenght is more than enough for my needs while I was getting a 1.02 SWR in the 450 frequency range. I hope this can handle the 32 inch Laird whip antenna too..

Heavy Duty Magnetic NMO Mount for CB, VHF, UHF, GMRS Radios with PL-259. RNMOM-195-SUM-B-12I-ST

 

 

[CyborgAlienWRYG738]

4 hours ago, WRZM228 said:

Thank you for the followup and information. I'll be getting the B4505CN chrome whip. It should be easier to tune and match that antenna too and hopefully they'll recommend me to keep this magnamount. I really like it and quite strong and 1/3 of a size of a K40 Magnamount. Its got a rubber feet, 12 ft LMR-195 cable and high grade connector. Th lenght is more than enough for my needs while I was getting a 1.02 SWR in the 450 frequency range. I hope this can handle the 32 inch Laird whip antenna too..

Heavy Duty Magnetic NMO Mount for CB, VHF, UHF, GMRS Radios with PL-259. RNMOM-195-SUM-B-12I-ST

 

 

How's the magnet strength on that?

[wayoverthere]

8 hours ago, SpeedSpeak2Me said:

Now, I do say "as a reference" because The Antenna Farm is closed until Summer of 2024, but they are still an excellent resource.  An alternative mount, which I have yet to hear anything negative about is the Midland MXTA12 mag mount.  It is also more readily available, and is 3.5" in diameter. 

 

First, I've had nothing good experiences with The Antenna Farm as well, and hope to see them get back on track in the new year.

Second, most of the mag mounts I've used have been the mxta12's, and they've worked well for me, both on that 32" 2x5/8 wave Browning, and the 36" long comet 2x4sr. They've hung on fine on the roof of my little truck even close to 90mph, along with dragging a signal stalk across all the ceiling beams in the 7' clearance parking structure at work (5 or 6 floors worth, depending where I found a spot). The only time it actually came off in the year I had it up was once, with a direct hit on the comet on a solid (2"+ diameter) tree branch

[CyborgAlienWRYG738]

9 hours ago, SpeedSpeak2Me said:

You're quite welcome for the information, and don't feel bad.  When I first got into GMRS I picked up one of the Nagoya UT-72G antennas based on other people's recommendations.  I got two from two different resellers and they were both junk.  The SWRs for simplex were 1.77:1, and at the repeater inputs it was almost 2.10:1.  Some will say anything under 2:1  is okay, but i just wasn't comfortable using something that was that far off, when I knew there was better.  I did have people tell me I got the wrong antenna, that I got the UT-72 (2m/70cm) by ignorance.  However I have that antenna as well, so I had a direct comparison (at the end of this post).  The UT-72 performs slightly better than the UT-72G on GMRS.

Having invested in the quality equipment (the RigExpert), it really lets me know exactly what is going on.  I did my testing on three different vehicles, all with more than enough area for a ground plane, and got the same results for both antennas (UT-72G) on all three vehicles.  Where some initial mistakes were made was using an inexpensive inline SWR meter, the Surecom SW102.  It's good for confirming your TX frequency and power (when used with a 50Ω dummy load), and that's about all I trust it for.  Others have had measured success with them, but when compared to a quality antenna analyzer, they just don't hold up.  At least that is what I have found with my use of them, YMMV.

I use 3.25" bases with both of my 32" antennas and have no issues, even at highway speeds.  You have to be careful with the base size, as I have found that too large of a magnetic base will impact your tuning.  For example I helped a person that purchased a 6" mag mount, and from experience I could tell before we did any trimming of his Laird BB4503 that something was wrong. The SWR's were way too high, and the "shape" (peaks/valleys) were in the wrong places.  We switched them to a 3.25" base and the antenna went to where it should have been.

The reason is, I believe, and more knowledgeable persons on here can correct me if I am wrong, is that due to the requirement of needing at least 1/4 wavelength ground plane (about 6.3" / 16cm), the diameter of the base was interfering with the ground plane itself.

For reference, this is the mag mount that I use, which has 12' of RG8X, and is paired with the BB4505CN or BB4502N.
Laird TE Connectivity GB8X

I also have this base with 12' of RG58/U, with the removable rubber boot, and pair it with the BB4505C or the BB4503.
Laird TE Connectivity GBR8PI

The GB8PI is the same as the GBR8PI, but without the rubber boot. So you're basically being charged $7-8 for the boot, which isn't required, nor does it hurt its performance.

Now, I do say "as a reference" because The Antenna Farm is closed until Summer of 2024, but they are still an excellent resource.  An alternative mount, which I have yet to hear anything negative about is the Midland MXTA12 mag mount.  It is also more readily available, and is 3.5" in diameter.  To go further with that, Midland's MXTA26 GMRS NMO antenna is also an excellent performer, and requires no tuning.  These two items are very often paired with each other.

I have Midland's MXTA13 mag mount, which is a 1/4λ, with a 1" magnet, 6" mast, and 20' of spaghetti (RG-174) for coax.  It performs better than I ever would have given it credit for, even with the massive amount of attenuation from the coax, which is about 20dB per 100', which is a lot.  However it works in a pinch for temporary use, and over flat terrain I can hit repeaters 30 miles away with just 15w.

As mentioned above (both antennas on the same vehicle, positioned in the same place).  Sweep is 400-500 MHz.
Red - Nagoya UT-72G
Blue - Nagoya UT-72

I've been looking at the GR8PI lately to fulfill my mounting needs. I like they're qualities, I was worried about the strength of the magnet though and being able to handle the ~3' antenna sitting atop it. Good to know the black version is capable. 

I think I'm going to get it and pair it with the B4505CN which I decided was the best choice for GMRS right now, for me. 

product-GR8PI.datasheet.pdfENG_DS_ANT-DS-NMO-Magnetic-Mount_0721_A1.pdfENG_DS_DS-ANT-B4505CN_1020-TE_A1.pdf