Mobile Antenna

[zzz]

I'm looking for any suggestions for a GMRS antenna to mount on my Jeep. 

[wayoverthere]

While the owners can talk in more detail, my first thought with all of the ground plane locations being compromised/shaded by the body, my thoughts always go to no-ground-plane required stuff.

https://theantennafarm.com/shop-by-categories/shop-all/mobile-antennas/300-512-mhz-uhf/no-ground-plane-antennas

I'm a fan of laird, too...

https://theantennafarm.com/shop-by-categories/shop-all/mobile-antennas/300-512-mhz-uhf/no-ground-plane-antennas/6536-laird-connectivity-bb4502nr-detail

[WRUU653]

1 hour ago, wayoverthere said:

While the owners can talk in more detail, my first thought with all of the ground plane locations being compromised/shaded by the body, my thoughts always go to no-ground-plane required stuff

I was wondering why more people don’t go with an antenna that doesn’t need a ground plane when one isn’t easily available.? Would it be safe to say all things being equal that an antenna with a ground plane is best?  Also is there any benefit to a non ground plane type antenna in an application that does have a ground plane?  

[wayoverthere]

20 minutes ago, WRUU653 said:

I was wondering why more people don’t go with an antenna that doesn’t need a ground plane when one isn’t easily available.? Would it be safe to say all things being equal that an antenna with a ground plane is best?  Also is there any benefit to a non ground plane type antenna in an application that does have a ground plane?  

From what I'm finding, all things equal, an antenna with a ground plane will have some advantage over one without. You can realize some of that advantage by providing it a ground plane, but some installations it just isn't feasible.

I will say on the ham side, I've noticed no difference moving from a comet 2x4sr mag mounted on the roof to a sbb5 on the fender, other than the rfi the sbb5 picks up being so close the led headlight bulbs.

[KAF6045]

6 hours ago, WRUU653 said:

I was wondering why more people don’t go with an antenna that doesn’t need a ground plane when one isn’t easily available.? Would it be safe to say all things being equal that an antenna with a ground plane is best?  Also is there any benefit to a non ground plane type antenna in an application that does have a ground plane?  

For comparison, a half-wave vertical dipole -- no ground plane required -- is twice as long as a quarter-wave vertical -- ground plane needed.

That makes for more antenna sticking up to be hit by tree branches if off-road, parking garages, etc.

[Lscott]

18 hours ago, WRUU653 said:

I was wondering why more people don’t go with an antenna that doesn’t need a ground plane when one isn’t easily available.? Would it be safe to say all things being equal that an antenna with a ground plane is best?  Also is there any benefit to a non ground plane type antenna in an application that does have a ground plane?  

Well, there aren't that many non ground plane antennas to choose from. Another point is a non ground plane antenna needs an internal load matching section. That adds bulk and cost to the antenna over a simple 1/4 wave design which needs a ground plane and no load matching section.

It's possible that more non ground plane antennas will be marketed as more vehicles employ plastic in the roofs and other body panels to save weight and cost. For those you don't have much in the way of options.

[zzz]

Ground plane will not be an issue in my circumstance. I have a nice little spot to mount to metal near the windshield.

[Sab02r]

Breedlove has some nice mounts:  https://breedlovemounts.com/store/ols/all

I had their pedestal on my Jeep and recently went to a Breedlove stake pocket NMO mount on my truck.  I ran a ground for each to the frame.

Some folks may push for something more centrally located on the vehicle than a stake pocket, but both of my mounts work great for my purposes.  The stake pocket mount with Midland antenna provided a SWR reading of 1.09:1 at the time of installation.

I also considered a unit that mounts under the hood.  This one is for a truck, but I have seen similar units on Jeeps:  https://www.americanradiosupply.com/2009-2014-ford-no-hole-antenna-mounting-bracket-fo2antpf/?gclid=CjwKCAiAr4GgBhBFEiwAgwORrcL5fTOTcrk1nlGEvw0fyHiCLQmaZgWGCyVoMiOPU0BGY1X7zswftRoC7pcQAvD_BwE