Rooftop 2-way radio antennas

[Left Coast Geek]

I will need a GMRS 2-way radio in my Expedition next year for an extended caravan... I've been advised that the handheld FRS/GMRS 'talkabout' stuff doesn't have adequate range... The GMRS radio I got, a Midland MXT115, has a magnetic antenna.... Oooops! The Expedition has an aluminum body?!? muahhhhhh.

I suppose I can use a double sided tape disk to hold it down ? :-/ But I kind of wanted to be able to put the radio away when we're not actually caravanning (maybe 1 in 4 days of this trip is travel).

 

[rd618]

I will need a GMRS 2-way radio in my Expedition next year for an extended caravan... I've been advised that the handheld FRS/GMRS 'talkabout' stuff doesn't have adequate range... The GMRS radio I got, a Midland MXT115, has a magnetic antenna.... Oooops! The Expedition has an aluminum body?!? muahhhhhh.

I suppose I can use a double sided tape disk to hold it down ? :-/ But I kind of wanted to be able to put the radio away when we're not actually caravanning (maybe 1 in 4 days of this trip is travel).

Use 3M Double Lock it’s like velcro but commercial quality.

 

[Left Coast Geek]

Industrial velcro is an excellent idea. I was thinking of just cutting a disk of iron/steel the size of the antenna mount, and attaching that with a VHB disk, then using the antennas magnet base as-is.... hopefully I can remove the vehicle side after this trip is done and clean the adhesive off the paint without damage other than having to re-wax or whatever.

 

[Gary Waugh]

I have a 2008 expedition and use a magnetic antenna mount? When did the expedition’s switch to aluminium roofs?

 

[rd618]

Industrial velcro is an excellent idea. I was thinking of just cutting a disk of iron/steel the size of the antenna mount, and attaching that with a VHB disk, then using the antennas magnet base as-is.... hopefully I can remove the vehicle side after this trip is done and clean the adhesive off the paint without damage other than having to re-wax or whatever.

The one I’m suggesting does peel off once you apply a bit of heat, just do it slow, if not it will remove the paint too.
Depending the weather, you might want to bring some extra with you. If temps on the roof get over 120-130 the adhesive becomes more playable, add in water and it becomes less strong.

 

[Greyeagle]

I don't know what type of antenna you plan on using but...
On the old CB radios we needed a gound plane to use as a receiver... the whip antenna is just the transmit side. On a metal roof the magnet sticks to the roof metal to form a ground plane for receiving.
They do make antennas for vehicles that doesn't have a metal roof like a motorhomes that use fiberglass or now adays rubber.
Any communication shop can assist or point you in the right direction..

 

[Left Coast Geek]

I don't know what type of antenna you plan on using but...
On the old CB radios we needed a gound plane to use as a receiver... the whip antenna is just the transmit side. On a metal roof the magnet sticks to the roof metal to form a ground plane for receiving.
They do make antennas for vehicles that doesn't have a metal roof like a motorhomes that use fiberglass or now adays rubber.
Any communication shop can assist or point you in the right direction..

Well, GMRS/FRS uses a little short whip, its like 462MHz UHF (CB is 26 Mhz AM, much longer wave).

The Expedition roof is aluminum, so it will serve as a ground plane, just non magnetic...

 

[Greyeagle]

Found this online...
Maybe it will help.
What antenna do I need for a GMRS radio?
Easy, you can use an NGP or No Ground Plane required antenna. We have found that the best antenna for GMRS radios where little to no metallic ground plane is available is the RFMAX RBC-450-5-NS. The RFMAX RBC-450-5-NS is a UHF whip antenna with an NMO base and NO metal ground plane required.Feb 3, 2021

 

[Left Coast Geek]

as I said, my roof is aluminum, so should provide plenty of ground plane. I'm using the antenna that came with my Midland MTX115 only issue is attaching it, since the antenna's magnetic base won't stick to aluminum.

 

[rd618]

as I said, my roof is aluminum, so should provide plenty of ground plane. I'm using the antenna that came with my Midland MTX115 only issue is attaching it, since the antenna's magnetic base won't stick to aluminum.

The 3m stuff I recommended already. The grounding plane is not relevant. You are also attaching it to a painted surface, which is a terrible conductor. Just go with the 3m double lock.