To NMO or not to NMO...

[KF5BET]

Ok, So I have really been considering drilling a hole in my f250 (although I do get pretty queezy just thinking about it).

I hate the look of the coax from the magnetic mount for the 2 meter just laying on top of the cab and then running through the door post.

What are your thoughts on a NMO right in front of the third brake light? I saw a youtube video of an installation there on a f150 and it looks pretty good.

I am looking for pros and cons both.

I know it sure does look nicer, but am concerned about leaks into the cab. What about signal strength if I were to put it that far back?

Thanks

Galen

[wa8yxm]

Well, regarding leaks.. There are thousands of NMO connectors installed on Thousands of vehicles and not many of 'em leak

If you are concerned you can put a small layer of GOOP on the seal washer, but frankly. I do not think you need it, Done right, and there is almost no way to do it wrong, it will not leak.

[One Country Boy]

Hi Galen,

I've had a couple of roof mount antennas like you are speaking of for 2 meters and 440. I never had a problem with a leak. If installed properly that should be the least of your worries. I'm in the same situation as you right now.

One other thing, the coax running to that mag mount will mark up the top of your vehicle or can.

I just had the Ford dealership where I have my F250 serviced run wires from the 4 aux. switches today. In preparation to install a 2-meter radio for our up and coming summer trip. For right now I'm going to use a mag mount. I put some duct tape on the bottom of the magnet, hopefully it will not mar or scratch the cab.

Your radiation pattern will be much better with your antenna mounted as close to the center of the cab as possible. I know the performance is not as good but I will probably mount mine on the center of my tool box later. I just cannot stand the thought of drilling a hole in the cab.

Good luck with your decision on where to mount the antenna.

~Jim~

[wa8yxm]

One thing I did on one car I had was buld a "Z bracket

Imagine the letter Z with the / being | and you have the design
_
|_

The bottom flat was drilled and a fender mount bolt was removed and re-inserted through the hole, the vertical flat went at the edge of the fender where the hood did not quite mate (The gap between hood and fender) the top flat was drilled for the antenna mount.

NO HOLES were drilled in the vehicle at all

The bracket was painted with Dupli-color spray to match the vehicle.

[One Country Boy]

Originally Posted by wa8yxm

One thing I did on one car I had was buld a "Z bracket

Imagine the letter Z with the / being | and you have the design
_
|_

The bottom flat was drilled and a fender mount bolt was removed and re-inserted through the hole, the vertical flat went at the edge of the fender where the hood did not quite mate (The gap between hood and fender) the top flat was drilled for the antenna mount.

NO HOLES were drilled in the vehicle at all

The bracket was painted with Dupli-color spray to match the vehicle.

This is similar to what I plan to do with my "tool box mount" John. I have a low profile diamond cut box in the rear of the F250. I'm going to mount it on the back side of the box, centered to the middle of the bed. It will be clear of the 5er there. Not the best way as far as performance but there will be no holes in the rooftop.

Galen, if you should decide to drill your cab for a roof mount, before applying the goop John mentioned, you might apply some sort of primer to the freshly cut metal to delay any rust.

It should last for years without any leaks.

Jim

[KB5LJE]

Guess I got lucky my truck purchased used and had the nmo drilled, mine has never leaked. I am thinking about moving my hf antenna from stake mount to the center of my toolbox also.

Mike

[W6DCS]

I used to install radios and emergency equipment on law enforcement vehicles and fire trucks. Never had one leak, and one I did on a fire truck is still on the roof 17 years later, and no leaks.

[dirtrod]

Real Hams drill holes, hi hi.
I’m still driving my 1987 F250, my 1995 Grand Cherokee and am ordering an NMO based antenna for my new Grand Cherokee that I bought last week. No leaks and it does rain here in Oregon from time to time.

[One Country Boy]

Originally Posted by dirtrod

Real Hams drill holes, hi hi.
I’m still driving my 1987 F250, my 1995 Grand Cherokee and am ordering an NMO based antenna for my new Grand Cherokee that I bought last week. No leaks and it does rain here in Oregon from time to time.

I like that, "Real Hams drill holes". Good one. When I was younger I would have never given it a second thought. Now, I have to think about it. Hi Hi...

Nice to have you "dirtrod". Thank you for posting. You and I are about as far as you can get across the country. Again, very nice to have you on the forum.

Jim

[Radio]

Had a NMO mount on my Ranger. I installed the thing initially myself and no, it did not leak. Drove under a tree. The center coil on the Comet dual bander caught in a vine and ripped the NMO right out of the roof.

Fix it myself, no leaks.

Put the truck in the shop for clutch work. Mechanic drives truck through partially open overhead door. (it was raining) NMO ripped off again, this time repairs on their dime.

No more NMO holes in anything I own. Mag mounts will leave the vehicle before doing any serious damage, like under trees or in parking decks. Most people are too short to see the the grubby place the magnet makes on the roof after 100,000 miles and the rest don't care.

In the car wash the antenna and mount go in the backseat.



But the thing put out a booming signal, I guess because of the excellent connection to the ground plane

[KF5BET]

Well, I picked up a new nmo mount today at a local hamfest. It is sitting on the desk staring at me!

We shall see...will keep you posted..

[n5rtg]

I wanted to eliminate the mag-mounts (11m & uhf/vhf) and their cables. Part of the reason was to put a Comet SBB7 58" dual-band, and I needed a beefier mounting solution. Could have put in a five-inch magnet but thought this was my big chance to finally put a hole in my truck's roof.

Even got XYL's permission to put two holes, one for each antenna. It wasn't too difficult, she's practical, she remembered I had knocked a mag-mount antenna off the roof and banged the side of the truck a couple of times. And I showed her info from K0BG's website on safety and where unattached things go in a crash (wherever they want, and where you most don't want them to).

Then, at a hamfest, decided to go instead with door mounts like the Diamond K-400. One on each rear door, mounted solid and grounded well. Looks great, works great, and no problem with the SBB7's length. Easy to fold-over or remove antennas from their nmo mounts on the door brackets for low parking situations.

My first post, just found this site from WA6CDE.

See you down the road,

Jim

[Andy N1ORK]

Welcome aboard Jim!
Glad you found the site and posted here. Be curious to see photos of those NMO door mounts.
73
Andy - n1ork

[n5rtg]

Andy,
I'll get a couple of pictures out soon. The cooler one is the Lift and Lay motorized mount on the trailer's roof -- from my operating position inside, I can raise/lower and tune the 80-15m vertical. I have 15,000 miles on this config and working great. Not as good as a dipole or beam, but wherever I go, there it is.

Thanks for welcome, talk to you soon,

Jim N5RTG

[WD8QBQ]

Welcome to the group Jim, glad you found us.
Looking forward to your pictures.

I'm getting ready for full timing, should happen in Sept., lots to do!

Where are you roaming now?

[AE5BI]

Not sure what year truck you have but back when I had my F350 there was a pass-through for wires behind the back seat. It is a rectangle with three rubber flaps through which I ran my antenna wires. I put a mag mount on the roof and then ran the wires using magnetic wire clips over to the rear corner of the cab so they didn't block the window. Can't remember where I got the clips, maybe Michaels. I didn't think it looked bad.

[KF5BET]

hmmm...just saw this post come back. Have not installed the NMO yet. It is still riding around in the console. I lost my mag mount a couple of weeks ago and now have a 2 meter 1/4 wave whip on the fender mount. The mag mount was a cheap one and it corroded pretty badly and would come loose at the base. When I tried to tighten it, it broke away from the base and now there is no way to keep it tight.

The fender mount works pretty good, but I did get a report of alternater whine (I am asssuming because of the proximity to the engine compartment).

I am still going to install the NMO, but am waiting for spring and warmer weather. I am also very busy with work and trying to get the ham shack finished here at the house.

[n5rtg]

We're in Okeechobee, FL for a couple of months. Heading up to Hamcation next week for four days, then another few weeks back here before we head to New Mexico, Arizona, Utah, Colorado, then Wyoming for April through beginning of July.

Full-timers almost three years, in a 25' Airstream trailer, N4RTG and I enjoy traveling together.

Pictures are up, more to add later. Door-mount brackets are soooo much better than the mag mounts we had. Best mag mount was our Larsen, it worked well for the 1/4 wave antenna.

We wanted more antenna, ended up with a Comet SSB7. Way too much antenna (58") for the small magnet, plus had knocked even the 1/4 wave antenna off and dinged the truck (who knew it wouldn't go under the garage door?). Hard-mounting was the only way I would go.

Ready to have a pro installer for two nmo holes in truck roof -- hey, it makes the truck more valuable when you trade. Just tell the salesman it is prepped for cellphone antennae. Anyway, I was ready then stumbled onto a good deal on a pair of door mounts.

A ham friend in Texas has this identical setup with the shorter 11m antenna on the curbside door and the 5' vhf/uhf on the street side door -- he really likes it, has been using the setup a couple of years. Looks good, works great. We set ours up Nov 2009 in Mesa, AZ, and are still tweaking it.

No complaints at all. Amazing improvement over the 1/4 wave whips for 2m (also changed the dual band on the trailer's roof to a 38" dual band Hustler). More antenna and more height has provided much more signal in and out.

Enjoyed talking to you,

Jim
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[KF5BET]

Thanks for posting the pics of the door mounts...I am very intereted in that setup...Going to do a little research on those. This might be a better option for me.

Glad to see you on here. Great bunch of folks...

73's

Galen