So I don't have pictures up as it was raining all weekend...but an experiment I've wanted to try for a long time has paid off quite well.
I have an 05 Jeep Wrangler Unlimited that I run with the hard top full time.
I've had my VHF/UHF antenna side mounted on the tub because the roof is fiberglass. The performance on the side mount just plain sucked. I like to work VHF simplex frequently too so this was even more of an issue vs the high density of repeaters in the area. 440 performance was particularly horrible with the side mount.
I'd run a Larsen 2/70B and that was useless without a proper counterpoise under it. I upgraded to a Diamond SG-7900 high gain and that improved things quite a lot, though it was still very sub-par for what it was due to the mounting.
So to fix this, I took a 30" square 3/32" sheet of aluminum plate, through bolted at each corner through the fiberglass top. The plate is on the inside. I used a thick mount NMO and put that through the plate and the roof.
The performance increase has been dramatic. A 440 machine from my driveway that is S1-S3 with a lot of flutter is now S6+ and DFQ. The local repeater on 2m, I would run out of coverage at about 15miles in varying terrain. I tested the new configuration out to 25-30 miles and could still hold a full conversation on the machine. Simplex is less definitive, but I'm able to hear the usual crew when I just plain couldn't before and the range is 15+ miles to most of them working on home antennas and 25W or so.
Just plain seat of the pants, audible improvements with generally strong machines is high too. Machines that were solid and usable are now completely DFQ. Courtesy tones sound like they are in high def sound heh.
Time will tell how it holds up in cold and hot weather, but I used shoulder washers top and bottom, 1/4" stainless bolts with lock washers as well. The worst part of it is bending the 'kick' into the plate to get around the internal reinforcing rib that was in the way. I used cabinet clamps and a piece of landscaping tie as a makeshift break. It worked, though a proper metal break would have made it look a lot neater.
I used some silicone caulk at the top and with the rain all weekend, things remained nice and dry on the underside, so that is promising too.
If you are a hard top sort of Jeep owner and like to play radio, I can't recommend this enough. For HF/10/11m use, you could put a sheet that is the full size of the roof in and bond the corners to the windshield and the rear corners of the tub too. I already have a ball mount on the right side and for HF it doesn't matter as much for the location of the counterpoise. I get decent 20m and up performance already.
I have an 05 Jeep Wrangler Unlimited that I run with the hard top full time.
I've had my VHF/UHF antenna side mounted on the tub because the roof is fiberglass. The performance on the side mount just plain sucked. I like to work VHF simplex frequently too so this was even more of an issue vs the high density of repeaters in the area. 440 performance was particularly horrible with the side mount.
I'd run a Larsen 2/70B and that was useless without a proper counterpoise under it. I upgraded to a Diamond SG-7900 high gain and that improved things quite a lot, though it was still very sub-par for what it was due to the mounting.
So to fix this, I took a 30" square 3/32" sheet of aluminum plate, through bolted at each corner through the fiberglass top. The plate is on the inside. I used a thick mount NMO and put that through the plate and the roof.
The performance increase has been dramatic. A 440 machine from my driveway that is S1-S3 with a lot of flutter is now S6+ and DFQ. The local repeater on 2m, I would run out of coverage at about 15miles in varying terrain. I tested the new configuration out to 25-30 miles and could still hold a full conversation on the machine. Simplex is less definitive, but I'm able to hear the usual crew when I just plain couldn't before and the range is 15+ miles to most of them working on home antennas and 25W or so.
Just plain seat of the pants, audible improvements with generally strong machines is high too. Machines that were solid and usable are now completely DFQ. Courtesy tones sound like they are in high def sound heh.
Time will tell how it holds up in cold and hot weather, but I used shoulder washers top and bottom, 1/4" stainless bolts with lock washers as well. The worst part of it is bending the 'kick' into the plate to get around the internal reinforcing rib that was in the way. I used cabinet clamps and a piece of landscaping tie as a makeshift break. It worked, though a proper metal break would have made it look a lot neater.
I used some silicone caulk at the top and with the rain all weekend, things remained nice and dry on the underside, so that is promising too.
If you are a hard top sort of Jeep owner and like to play radio, I can't recommend this enough. For HF/10/11m use, you could put a sheet that is the full size of the roof in and bond the corners to the windshield and the rear corners of the tub too. I already have a ball mount on the right side and for HF it doesn't matter as much for the location of the counterpoise. I get decent 20m and up performance already.
