As we all know, or at least should know, 1/4 and 5/8 wave antennas require ground planes to radiate our signal properly. This makes antenna installations on our fiberglass hard tops somewhat difficult.
Over the years, I have collected many NMO mount mobile antennas. Every new vehicle I've owned since 1991 had a 3/4" hole drilled in the roof and antenna mounted within the first 5 days of ownership. Sadly, it's taken me just over a year of off and on thinking and running ideas through out local Brain tRust on how to use roof mount antennas on my hard top JKR.
Here is my solution.
First, drill a 3/4" hole in the center of the hard top. I used a step bit and a round file to clean things up.
Next, drill a 5/16" hole on the side at the front end of the center brace. I also drilled a 5/16" hole immediately below the 3/4" hole through the center brace. Drill this hole from the outside of the top going through the 3/4" hole. This will let you have the 5/16" hole somewhat centered in the 3/4" hole.
Using a coat hanger, I put a small 90 degree bend at the end of the wire. I then fished the coat hanger wire through the 3/4" hole and managed to get the small bend to come out of the 5/16" hole at the front. I taped some twine to the coat hanger and pulled the twine from the front end to the 3/4" hole in the center of the roof.
Next, I used a 4" piece of 1/2" grounding braid and soldered it to one of the bottom pieces of the NMO mount.
I then attached the twine to the end of the coax that is part of the NMO mount. Starting on the outside 3/4" hole, I pulled the coax through that hole, through the center brace and out of the 5/16" hole at the front of the top.
When the mount itself was near the 3/4" hole, I folded the braid in half and fished it through the 3/4" hole and then through the 5/16" hole in the center of the roof. I then VERY gently, worked the 3/4" hole mount through the 3/4" hole, using a very small screwdriver to push the braid and mount through the hole.
To be continued.......