You can get a thick mount NMO that has an N or SMA connector on the bottom side instead of permanently attached coax. For a no ground plane VHF or UHF antenna I would recommend installing three snap on ferrites of a #43 mix or Laird 28 mix near the mount as the no GP antennas mounted on an insulator will try to use your coax as a ground plane and that can make the coax hot with RF.
Holy signal batman! That's one heck of a setup! What's that mushroom looking thing? A sat antenna maybe for a Garmin? It looks pretty well built - but like @Radio Guy mentioned I am curious if you have done any functional testing yet to see if its maybe too much metal?So I finally got the major parts of my ground plane project finished. As noted prior this will serve as a ground plane for 1/4 wave antennas for a GMRS radio and another 2 meter/VHF radio. The roofrack will also function as a roof rack if needed and the ground plane will act as shade for the roof keeping the temperature down inside during summer.
The area where the two radio antennas and the Sirius antenna go through the roof. So far no leaks. The Sirius antenna needed to be moved because the metal blocks it from working.
The front of the truck with the roofrack
The antennas and the ground plane. I decided to build a little extra platform for the GMRS antenna because I didn't want it in the "valley" of the roofrack and figured elevating it a few inches couldn't hurt its distance transmission.
It was pretty arduous sourcing parts. All the hardware that is not antenna is aluminum. Aluminum bolts, aluminum spacers, aluminum roofrack, aluminum sheets. I went with the aluminum roofrack because I'm older, working out of a garage, and therefore could use the lighter weight. All the other aluminum parts were to prevent galvanic corrosion processes.
NMO mount isn't going to work for that unless it's a custom deal. I dont think anyone makes one that is long enough to go through the top. From watching videos of people drilling through them I think it's pretty thick with some open dedspace in the middle.
I would not use a single counterpoise and use at least two or more “radials” heading in opposite directions or a 12” dia conductive sheet. Or a 12” long strip of 2” wide aluminum HVAC tape with the mount planted in the middle.
OMG lol sorry but that is funny
Crap! Was 'sposed to READ the directions?
If you provide an adequate ground plane you can use any GMRS or UHF antenna and not be stuck shopping for a NGP type. A 12” round disc or square sheet is a good size ground plane for GMRS or make an X with some 2” wide aluminum tape that is 12” across with the mount in the middle.
