Mag-Mout on a rag-top Jeep?

[DJ-Person]

I have a Jeep Wrangler with a soft top. The only steel in the center of the roof is the support bow (<1” tubing) I was wondering if putting a strong magnate or plat of steel on the inside of the fabric top and my mag mout on top of it outside would work. I can figure out the structural problems. But what electrical problem would there be. And how could I fix it. DJ

 

[donc13]

I have a Jeep Wrangler with a soft top. The only steel in the center of the roof is the support bow (<1&#8221; tubing) I was wondering if putting a strong magnate or plat of steel on the inside of the fabric top and my mag mout on top of it outside would work. I can figure out the structural problems. But what electrical problem would there be. And how could I fix it. DJ

Unless you welded, or otherwise electrically bonded a sheet of steel to the roll bar, you'd be much better off simply using a magnet mounted antenna mounted on one of the "shelves" above the rear wheels. I have a Wrangler also, mine's got a hard top...but it's plastic, and I've got a GPS and Satellite radio antenna sitting (magnet) on the top of the roll bar...under the padding and they work perfectly. I've also got a scanner antenna mag mounted above the rear wheel, on the "shelf" as I suggested to you (behind the driver) and it works great there.

 

[rcvmo]

I've done a few jeep grass truck installs where we've permanently installed the antenna in the middle of the front hood. I also did a few installs where we welded a plate on the roll bar as well. Not too many other options on a vehicle like that.
Happy New Year.
Stay Safe!!
rcvmo

 

[NeFire242]

You could always use an "L" bracket along the front hood. With a mag mount on the top of the roll bar I'd worry of it flying off and hitting someone or the vehicle behind or near you. Plus you may not have enough of a ground plane for this type of setup.

 

[DJ-Person]

Ground wire / ground plane / paralel leads

Hay Don, how do you get the antenna from the roll bar through the fabric top? Do you only use it when your top is off?

My jeep is a 2007. The fenders are 100% plastic. So no magnates there. I drive it on-road so I worry that a cop will pull me over if it is on the hood, obstructing my view.

Would running a ground wire to the antenna base work? Would running the ground wire bundled with the antenna cable degrade the signal?

How close to the ground plan does the antenna need to be? The roll bar, windshield frame, door window frame and support hoops are the only steel within + - two feet of the top.

What could suffice for a ground plane? The good old cookie sheet under the top?

Thanks again for the help, DJ

 

[w0fg]

Here's the way to do it right.
http://www.4wd.com/productdetails.aspx?partID=41221

 

[Scoobert]

What is the fascination in mag mounts? Why not get a regular mobile scanner antenna and install it on a cb antenna mount, like a tera flex?

My cb antenna (4 foot Everhardt) mounted on a driver side teraflex mount. The scanner antenna will be mounted on the same type of mount but for the passenger side. The driver side is easier to install though
Click-able thumbnail.

 

[blinddog50]

DJ,
www.arizonarockyroad.com
I use Rick's products on a 2005 Rubicon.
Products are great and customer service is fantastic.
Should solve your problem.

 

[DJ-Person]

Great feedback on my questions! I have a CB antenna on the left side, it would have to be a right side mount. Does this come in left side configuration?
I understand that higher is better. This tailgate set -up would not hold my antenna tip more than 2” or 3” above the spare tire! My Larson is only 19” long. It would mount several inches lower than the hood line.
Does the antenna need to be in the middle of the ground plane? i.e. center of hood or top?
I’d have to buy another antenna cus I still need the mag-mounted one for my other vehicle. And I’d need another length of cable & a mount for that bracket, >$75 total increased cost.
Still no info on what would be a good ground plane or if parallel ground wire and antenna leads would cause a problem. ( I would run a ground wire with the mag-mount lead if that would solve the ground plane problem. )
DJ

 

[breadtrk]

Ground wires from the mount out to the corners, then down to the frame might do as a reasonable ground plane. 1 wire, no matter how you run it is not going to be very good. You could attach them to the plate you want to add under the top for your mag mount to stick too. How you are going to keep it upright on a soft top, and how you plan to keep the corners or edges of the plate from ripping a plate sized hole in your roof is up to you.


Best thing is to bite the bullet, fabricate something with metal, bonded to metal, high enough to clear the roll bars, or just make do with an 800mhz whip on a hand held.

 

[donc13]

Hay Don, how do you get the antenna from the roll bar through the fabric top? Do you only use it when your top is off?

My jeep is a 2007. The fenders are 100% plastic. So no magnates there. I drive it on-road so I worry that a cop will pull me over if it is on the hood, obstructing my view.

Would running a ground wire to the antenna base work? Would running the ground wire bundled with the antenna cable degrade the signal?

How close to the ground plan does the antenna need to be? The roll bar, windshield frame, door window frame and support hoops are the only steel within + - two feet of the top.

What could suffice for a ground plane? The good old cookie sheet under the top?

Thanks again for the help, DJ

The roll bar is under the top, so no biggie. The 2 antenna I have mounted on the roll bar itself are satellite antenna, one for GPS the other for XM Radio. They're small, about 2" in diameter and have a magnetic base. So I just unwrapped the padding, plopped the antenna on the roll bar (one on each side) and ran the feedline up, under the padding into the front by the windshield and then down to the radios.

As to the scanner antenna, it sits inside also, on the "shelf" between the front and rear mount for the rollbar (over the rear wheel). It's a much larger antenna (a Larson 150/405/800) but works very well from that location.

Yes...ideal location would be center of the hood...but that's kind of ugly (to me) and I don't think it'd be that much better than where I have it currently.

Fabric top or hard top (plastic)...doesn't matter...the fabric or plastic won't attenuate the signal enough to make any difference. Obviously, if you were going to put a "normal" antenna on the roll bar, or on a sheet of metal welded to the rollbar....getting it to stick up through the fabric would be a trick. I suppose if I absolutely had to have something like that, I'd go with a car-top carrier (they bold to the fenders and sit over the roof) and put the antenna on it. Be kind of expensive, but it'd work fine.

Yes, a physical ground helps, but remember...a "ground plane" is merely a reference point for the antenna itself. Typically, it's the other half of a dipole. So the larger ground there is, and the better bonding to the actual metal frame of the vehicle...the better the antenna works. Again...it's all relative....we're not taliking huge differences, but they would be noticable between a well grounded antenna setup and one without a ground.

Another option (I use in my RV) is a marine antenna. It's designed not to need a ground plane. But I don't know of too many marine antenna that are useful for more than 150MHz. In my case, the Marine antenna is for XM radio...so it's small, works very well.