Mobile Antenna Mount Question

[RFnoob]

New member, going for my Technician license next week and I wanted to ask this before I do something dumb. This post might belong in the "equipment" section, sorry if it's misplaced.

Basically, I'm thinking about starting out with a 50W mobile dual (maybe tri) band radio for several reasons that don't much matter. The problem is how to mount the antenna to the vehicle.

I don't want a magnet or suction cup mount. I tried that with CB on a previous vehicle and we get just enough dust and rain here that it destroyed the paint under the mount in about a year. I just rebuilt this car and had it repainted so I'd rather put a few discrete holes in it with stainless sheet metal screws and then treat the holes rather than wreck the paint on the roof.

The problem is that this particular vehicle, a 1997 Jeep Cherokee, isn't the easiest thing to find mounts for. However, I know that there are a few CB mounts from companies like Firestik of the type I'm looking for that will mount under the hood and snake up and around between the fender and the hood so the antenna can be on the passenger or driver's side front of the car, slight off to the side which is how I prefer to mount my antennas anyway.

So, the question is, will a CB mount work with a dual or triband antenna? Provided that it's grounded properly I can't see a problem but I'd rather ask and look dumb before damaging a radio or punching holes in the car rather than ask after I've created a problem for myself. So, does such a mount 1. not cause problems for a dual/triband antenna and, of equal importance, does the hole in a CB antenna mount work with a dual/tri band antenna or will it require modification to the mount?

Thanks.

 

[buddrousa]

Jeep Install

My stepson is an avid off-roader and his new Jeep Wrangler Rubicon is his pride and joy. He calls it a "Lego set for adults". He was looking for a GMRS radio for it, with the ability to use for ham ops when he gets his ticket. We chose the Anytone AT-5888UV-III, a 2m-440-220 rig that has Part 90...

forums.radioreference.com

 

[APX7500X2]

An NMO mount in the center of the roof would be the best and with the large roof you would get great performance from it

But if you do not want to put a hole in the roof...

JCR Offroad XJCB-PC-97-PS CB Antenna Mount - Passenger Side for 97-01

JCR Offroad XJCB-PC-97-PS CB Antenna Mount - Passenger Side for 97-01 Jeep Cherokee XJ Description Easily mount a CB antenna on your Jeep Cherokee with JcrOffroad's slick and sturdy mount. CNC cut and formed from 1/8 Steel. Bolt on, no drill installation! Powder coated Black. Includes JcrOffroad...

www.passion4x4store.com

https://www.quadratec.com/products/96080_55_07.htm

 

[mmckenna]

Those hood bracket mounts can work, but you do want the correct antenna mount to install on it. The 3/8x24 stud mounts used by CB are not your best choice for a multiband antenna like this.

One issue you need to consider is that on the higher frequencies, putting the antenna down below the roof line is going to impact performance. It'll work, but it will have drawbacks.

Ideally you want the antenna centered on the roof. The antenna wants to see a flat ground plane under the antenna base in all directions. On the lowest band you'll likely use with this setup, it'll want to see about 19" in all directions under the antenna. Only place to get that is by doing a permanent mount on the roof.

Yes, it requires a 3/4" hole, but if you use the right components, you'll have an antenna system that will easily outlast the truck.

Getting the antenna up high and in the clear is going to give you the best performance. Anything else is going to introduce compromises.

 

[k9wkj]

XJ !
pop out the dope light saw the hole for a NMO mount
fish the coax to the B pillar and run it down the trim and under the seat
literally takes 10 minutes to do a pro level NMO install on a XJ

 

[RFnoob]

Jeep Install

My stepson is an avid off-roader and his new Jeep Wrangler Rubicon is his pride and joy. He calls it a "Lego set for adults". He was looking for a GMRS radio for it, with the ability to use for ham ops when he gets his ticket. We chose the Anytone AT-5888UV-III, a 2m-440-220 rig that has Part 90...

forums.radioreference.com

The NMO mount a bit farther down the page, on the grey Wrangler seems like my best option. With the right antenna I might, just MIGHT, be able to finagle it on the top of the hatch with the right antenna.

The other part of this that I didn't mention is that my spare tire is on top of the car and I often park in a garage with low clearance. I'm simply not in the position to mount things to the roof unless they're extremely compact, like... no more than 8" above the plane of the roof.

Everything I do in this regard is going to be a compromise one way or another, so the one that works reasonably well and doesn't destroy the radio or the antenna, by running it into things five days a week, is going to be the way I end up going. I simply don't really know that much about all the various options.

The guys at HRO are going to haaaaaaaate me asking them a bazillion questions about this, but at least I got some of it out of the way here.

 

[RFnoob]

Those hood bracket mounts can work, but you do want the correct antenna mount to install on it. The 3/8x24 stud mounts used by CB are not your best choice for a multiband antenna like this.

One issue you need to consider is that on the higher frequencies, putting the antenna down below the roof line is going to impact performance. It'll work, but it will have drawbacks.

Ideally you want the antenna centered on the roof. The antenna wants to see a flat ground plane under the antenna base in all directions. On the lowest band you'll likely use with this setup, it'll want to see about 19" in all directions under the antenna. Only place to get that is by doing a permanent mount on the roof.

Yes, it requires a 3/4" hole, but if you use the right components, you'll have an antenna system that will easily outlast the truck.

Getting the antenna up high and in the clear is going to give you the best performance. Anything else is going to introduce compromises.

Thanks for the heads up on the 3/8x24.

The problem with a bunch of this for me is that the closest place I can actually physically touch (or closely examine without touching) most of this kind of equipment is dang far away and these interwebz things mostly just don't give you a good idea of if things fit together or they don't answer your specific question.

Every time I tried searching for information on this all I got was how to run two CB antennas. So I figured I'd ask some people who know.

Thanks.

 

[ladn]

So, the question is, will a CB mount work with a dual or triband antenna?

Congratulations on getting into ham radio!

Go with an NMO through the roof mount., maybe two. And buy quality mounts like Larsen, Laird, PC-Tel. There's not much price difference between these and the knock-off Chinese mounts, but the quality is far better. Same for your antennas. NMO is the industry standard mount.

In town, I use a simple 18"-19" VHF antenna on my 4Runner since it doesn't whack as hard in parking structures. The antenna works on both VHF and UHF. My antenna is anodized black to make it a bit less conspicuous, but this has no effect on performance. In the backcountry, I switch to a Larsen NMO 2/70 for a little better performance.

I suggest two mounts (spaced well apart) because this will let you use one mount for your VHF/UHF ham antenna and the other mount for a CB or scanner antenna. The Larsen NMO 27 is a very good CB antenna.

 

[krokus]

I had one of my XJs for a long time. Having a dual band antenna mounted like k9wkj mentioned was very useful. My NMO was just after of the dome light. Stick with a shorter antenna, to avoid unnecessary impacts against overhead objects.

I had a CB antenna mounted on the hood, with what is typically used as a trunk mount. (It was a K40, and it served me well, but it sounds like there are better options these days. I did like the ability to quickly remove the antenna, when going into parking structures, car wash, or on a ferry.)

 

[Project25_MASTR]

Don't know if the OP ever got this figured out or not but I'd figure I would add my $0.10. If your XJ has the overhead console, that's a pretty easy place to start. Don't know how easy they are to get out on OBS XJs but NBS XJ's it's two Phillips screws at the front and then you just slide the console towards the rear and it releases.

I run a VHF whip on the roof of mine just above the console and then a 27 MHz antenna on the fender via an L bracket.

All of my radio decks are mounted under the back seat.

Speaker is hanging from the console. It's a good place for it but people are constantly hitting their head on it getting into the vehicle. Allows you to hear with the windows down going 70 miles an hour with the aggressive 32's.

Here's where I stuck my control heads...many disagree with placement on the dash but for a vehicle that rarely sees pavement it is not a big deal.

 

[K6GBW]

Long term, the NMO through the roof will be the least amount of trouble and work the best. The dome light gives you access. I like to go slightly behind the dome light and use a step bit to make a perfect hole. You can fish the coax across the headliner to the B pillar without have to take the whole car apart. Use a decent antenna like a Coment B10NMO and you will be golden!

 

[lu81fitter]

Clearance should not be an issue with that NMO mount on your roof. The top of my truck is about 77 inches. My garage door is about 84 inches. I drive in and out all the time with an 18" whip on there. No damage to anything. One time, by accident, I had a spring loaded Larsen tri-bander on there and forgot. It bent it over as I drove in. There was no damage that I could see, but I wouldn't want to do that again.