mobile antenna install ideas

[fez_uk]

Hello people.

In a few months I plan to get my own first ever vehicle and as a keen radio enthusiast I am looking for some advice/guide on possible mounts for 2 dualband vhf/uhf (hopefully the same kind).

I am thinking about drilling 2 holes for them and using hole mounts but there isn't alot of info/items about for that sort of stuff in the UK. Also the whole process seems very daunting.

Im asking for some advise on do's and don't on the process and maybe someone knows of any items that can be bought here in the UK. If not then maybe I will need to buy the mounts/antennas from the usa.

Also say if i was to sell the vehicle what would I use to seal the holes?

Thanks in advance guys.

 

[AK9R]

One of the most common antenna mounts in the U.S. for VHF/UHF land mobile antennas is known as the "NMO" mount. They install in a 3/4" diameter hole and seal very well if properly installed. In the U.S., you can buy NMO mounts from Radiall-Larsen, PCTel-Maxrad, and Laird-Antenex. I don't know what kind of international presence these companies have, but you may be able to find their products, or similar products, in the U.K.

You will want to take your time before drilling the hole for the antenna mount. If you want your antenna mounts in the roof, you will have to find a way to fish the antenna cables between the roof and the headliner. It may be easier to just take the headliner down. That's what I did when I installed mounts on my Ford Expedition. If you can spot the antenna mounts near a dome light, you may be able to take the dome light out and gain enough access to the underneath side of the roof. If your car has a trunk ("boot" to you, I believe), you can mount the antennas on the trunk lid and fish the cable through the rear seat area into the car. Whether you go for the roof or the trunk lid, be careful to not drill into any electrical wires and also watch out for stiffening ribs below the surface as they can be difficult to drill through.

For drilling the holes, I used an Irwin Unibit. This is a step drill that increases the diameter 1/16 of an inch at a time. The drill worked very well and left only slight burrs to clean up.

Most of the manufacturers of NMO mounts also sell 3/4" diameter plastic plugs that you can use to seal the holes when you sell the vehicle. Or you can just put a cell phone antenna on the mount and tell the potential buyer that it's a special feature. There is lots of debate about how much resale value you lose by drilling holes for antenna mounts. You have to weigh any potential price reduction against how long you expect to keep the car. Selling a 1-year old car with antenna mounts may be a challenge, but on a 10-year old car, the potential buyer may not care.

 

[fez_uk]

Well I have found some drill mounts one type for 3/8" mounting and the other is for SO239 connections.

Can't find many dualband vhf/uhf antennas that use 3/8" mounts so ill probably be going for the SO239. 2 main antennas are cropping up. One is 48cm and the other like 92cm. Im thinking 92cm might be a bit long.

The car i plan to get is a suzuki vitara (3 door or 5 door undecided yet). And plan on probably mounting the 2 antennas near the back near each corner area.

How hard was it to take the headliner out? And from there where did you run the coax to the radio?

 

[Grog]

A roof mounted SO239 is a disaster waiting to happen. It's not meant to be waterproof, while a properly installed NMO will be.

They also make NMO plugs for when you are done, just a simple rubber thing that fits in the hole and seals it. A guy at work bought a used fleet car and they are still just as water tight as when he got it in 2000. I might be able to find some at work and take some pics if you really can;t find any, but any radio shop should have them, even on the wrong side of the pond

 

[mrweather]

There are 3/8" NMO mounts as well but they're not as common as the 3/4" ones. And I agree with the SO239: they're not waterproof at all and are a disaster waiting to happen if you go that route.

My last car had two NMO mounts (one trunk, one roof) and the dealership didn't care when I traded it in (it was only 2 years old at the time). In fact, the trunk mount I turned into a "homebrew" XM satellite radio antenna by hollowing out an NMO rain cap and stuffing in the little PC board that came from another XM mag-mount antenna I had laying around.

The used car manager was impressed and requested the trunk-mount XM antenna stay with the car.

 

[fez_uk]

well there the only 2 types of mounts sold here in the UK. Heres a few links of them.

http://cgi.ebay.co.uk/SO239-BODY-MO...oryZ4672QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.co.uk/SIRIO-SO239-B...ryZ48694QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.co.uk/DV-3-8-CB-aer...VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

I was planning on using some conductive copper grease on the threads to help them seal.

hmm. I'll have a look around some US sites as not many people here drill holes into their vehicles for antennas.

Edit: Ok had a look on ebay worldwide and I can get the mounts pretty cheap. Can anyone know if they make dualband antennas for nmo mounts?

 

[fez_uk]

Ok found a shop that sells basicly all I need base + antennas. At good prices.

http://cgi.ebay.co.uk/Dual-Band-VHF...ryZ53107QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.co.uk/Dual-Band-VHF...ryZ53107QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

2 of one of those may take my fancy in a month or 2.

 

[hoser147]

Ok found a shop that sells basicly all I need base + antennas. At good prices.

http://cgi.ebay.co.uk/Dual-Band-VHF...ryZ53107QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.co.uk/Dual-Band-VHF...ryZ53107QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

2 of one of those may take my fancy in a month or 2.

I believe one of these two should serve you well, the others look more like a fender type mount................Hoser

 

[fez_uk]

aye, the first seems a bit too big so I am likely to go for the smaller antenna at 20".

thanks guys.