Extreme

Oh yeah. The bumper/taillight tower is pretty stout steel and the distance from the window is a few inches. I can shake the jeep with the tower. 3/16" thick x 8 x 8" aluminum plate for the ground plane base. I dunno what the 'modern' 3rd light towers are made of. This bumper is Currie, which isn't even made anymore so probably '08 vintage or so. Tested for the rear wiper and it clears by 1/2" or more. And the antenna is low enough it won't catch branches unless I hit the roll cage, or very close and 8"sq. is plenty of ground plane for 1/4 wave antenna, which allows me to keep it short instead of the 1/2 or 5/8 wave 'no ground plane' whips. Been there done that with the same setup on my SxS kayak rack; cost me a radio keying the mic with no antenna. FWIW fiberglass has no affect on RF. I'll check reception with a pal in front and again behind. Some nay-sayers out there in 4x4 land about GMRS (ham fans - and yes, ham is better at a lot of things) but for our trail usage they're great. And we have access to 2 repeaters nearby, one of which I hit from 50 miles with a 30w 8180. Considering putting one up on an existing tower on the edge of a nearby wilderness area we frequent off-road. See my post about recovering a stranded hunter, only because he had his HT GMRS on scan and heard us going by.

Antenna mount is done. Thank you rivnuts. Will terminate with PL259 and mount Kenwood TK8180 tomorrow. Sent from my Pixel 4a using Tapatalk

Picked up a new to me 2006 TJ Unlimited recently. It has a Rock Hard aftermarket rollcage so lots of space for radio mounting (Kenwood 8180). After yanking the CB I pulled the CB antenna cable back to find where it went - I'll keep that in place for a snake. The Currie bumper on the back has the high mounted 3rd brake light (steel) and a hole where the CB antenna was. I'm going to take an 8" x 8" x 3/16 aluminum plate, mount it to the top of the light bracket and run the cable along with the brake light wiring. Good ground plane, not totally exposed to overhang and enough above the fiberglass roof (when it's on there) for decent propagation 1/4 wave, 6" antenna. Yup, I ran the formula for proximity to RF.. no problem Yup, I'll post photos as it progresses. For now, I tore out the high-tech, but dated stereo (NAV, BU Cam, DVD, CD, amps, 2 subs and box in the cargo area and will replace with a decent Bluetooth/USB stereo while keeping the quality speakers that came with the conglomeration. It was a nice install but it's a Jeep and I'm busy on the trail, know where I'm going and have phone/tablet apps for all the other junk, and I rarely listen to music at my ripe old age anyway. My son-in-law, the stereo guru will put some or all of this in his 90-something boat for family outings. Win-win.

Great tool. Entered conservative (worst case) parameters. 1. Full radio power (30w) w/o cable loss. MSD drops considerably if I go to 20w for cable loss. 2. Transmit for a full minute is rare. 3. Antenna gain is what they said is normal for quarter wave vertical. (1.5) 4. Included Ground Reflections since the hood of a Jeep is considerably larger than the minimum requirement for a ground plane antenna and will be completely reflective. Looks like minimum safe distance is 1' to 2.5' depending on whether Controlled Environment. That's good, no danger while cruising and I certainly wouldn't let a bunch of folks have lunch over the hood while chatting on the radio. So I'll be quite comfortable transmitting from the driver's seat. Unless someone comes up with a mounting position that'll work as well, full ground plane is hard to beat. And we do get significant distances apart on the trail as well as varied terrain and elevations. Now I'm wondering if underhood heat will effect the coax? Thanks BoxCar!

Picking up my '06 Rubicon Unlimited (LJ) and pondering the antenna mount. I too have the Rock Hard cage so the radio mount is a no-brainer. In fact the previous owner has a CB mounted there now. I'm wondering if spare tire antenna mount will be as efficient as a ground plane antenna? Are you using a no GP? Reason I'm back on this thread is I'm planning to put a GenRight full hood vent on the LJ. I'm getting a spare TJ/LJ hood to monkey with so the original can be replaced if needed. Not wanting to cut up a rig with 29,000 miles on it. So... with the steel hood vent I can mount a 1/4 wave 6" antenna in the center of the modified hood and have a great ground plane. Question: is RF of any concern with only 4 or 5 feet and a windshield between the antenna and occupants? The look? Who cares if it works. Black antenna on a black hood and a total of 7" extruding. I'll read on.. haven't been on here in awhile, like since July. Thanks.

I for one have always had in the back of my mind an emergency situation where a GMRS radio would save the day. But, as we all know, traffic is slim and folks monitoring for emergency calls is minimal. So, my Offroad club does volunteer/pro-Bono vehicle recoveries. Got contacted by a guy who was stuck at 8500' but lucky enough to have cell phone coverage due to the proximity of a large but remote mine, end of the road, 50+ miles off pavement. We got him recovered after a 2 hour drive to get to him 5 miles off the main dirt road. But that's not the story. The story is: while in route to recover #1 we're chatting on Ch. 16 truck to truck (my Kenwood 8180 and 2 of my 905G I hand out to my compatriots). We're many miles from anywhere gabbing away on the trip when I hear an unfamiliar voice. I ask who it is, he says his name and tells me they've slid a Toyota Sequoia off the road and need help. I asked how he got us and he said he put his Baofeng HT on scan and heard us chatting. Told him we'd get him on the way out from #1. This Toyota was at the top of the Ruby Mountains, Harrison Pass at close to 10k feet elevation, 30 miles of dirt then 6.5mi in, 4wd/Low Range for 6.5mi. They'd walked out 8 miles from their rig to their camp (muzzle loader deer hunt). Without giving you all the details of the recovery (didn't get it done last night with 3 capable Jeeps with winches and recovery gear in darkness; he's since hired a pro and they're in route as I write). Anyway, just a little story on how screwed these guys would have been and how lucky they are to have had a radio and someone in range. I suggested they hit the slots; even tho' their luck was bad getting stuck, they got good luck just getting out of there. No telling how long they'd been there with no comms. They spent the night in a local motel since the Toy is there only rig.

50 is my personal best, over land. Sent from my Pixel 4a using Tapatalk

Yup, and the fix for the problems I had is in here (from that thread). That is no guarantee it will help with the OP's issue. "It just so happens that I have a copy of RT76P.exe version 1.45, which does allow you to modify W/N. (I actually broke my Retevis programming cable, so I replaced it with a generic one from Amazon for $9.99 - no big issue.)" https://1drv.ms/u/s!AjoUJvZyt8o5iOIgB8Bx6ElB3Hz9DA?e=BqVkCZ

https://www.pacparts.com/model.cfm?mfg=Kenwood&model_id=TK8180&row_start=1&src_model_id=tk-8180&action=list_part 2 Flex Cables on this page. If you've had the faceplate off you should know which you need.

I have a few 8180s in the 30W version and it worked fine for all. axorlov is correct, the 'H' is high power and K1/K2 is the firmware edition probably. The manual for all the 7180/8180 series is the same and software is shared. I've had no issues using 49D software on any of mine and once one is done I simply upload from that one then download configuration to a new one so they're identical. Run with it and don't sweat.

Update us on the performance of your new install when you've done some testing or real world use.

Very mountainous where I am and the 450 works great. Sent from my Pixel 4a using Tapatalk

The Larsen AB450 that I linked is a 1/4 wave antenna with 6" whip. OVERALL length mounted on the roof is measured @ 7", which I gave him due to his concern for overhead clearance on a lifted vehicle. https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=191_192_196_213&products_id=4476

Correct, it's not. He linked to what he described as "the wrong antenna". (I had been looking at the wrong antenna's I guess. Most were like this one. https://www.buytwowayradios.com/wouxun-ano-050g.html which is 31".) Since, we've been discussing the 7" 1/4 wave he ordered.

Aha.. perfect. That antenna will work great.

You might be surprised how well the 1/4 works with repeaters. But then the repeaters I use are at 6-7000' elevation. For you to get that in Texas you'd have to go to New Mexico..lol. Sent from my Pixel 4a using Tapatalk

Apparently the 'fresh' batteries I put in the Kenwood alkaline pack were not. New fresh and it seems fine but I wonder how well they'll hold up with the data you have. The 3170 would simply revert back to the power on screen when I keyed the mic with the others. Guess I gave up too early. Will try the Wouxun 805 again with new AA batteries and post results.

If exposed to the the elements I use Duct Seal. Sent from my Pixel 4a using Tapatalk

AB450. "Unity" gain. Zero. Work fine. Gain is overrated/misunderstood maybe. https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=191_192_196_213&products_id=4476 Sent from my Pixel 4a using Tapatalk

I run these because they require only a 3/8" hole instead of 3/4" and I can drill with a uni-bit + finish with 3/8" instead of a specialized hole-saw. They're also available for different thickness mounting surfaces. I don't know if they're susceptible to water intrusion but no issues for a couple years. My rigs are garaged 90%. https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=264_266_1291&products_id=1154

Should be no issues with a roof rack. Even a fiberglass/plastic kayak on the roof, covering the antenna will not block signal. 1/4 wave is 7", phantom is 3.5" and both will easily unscrew to remove, and a threaded NMO cap is available from antenna dealers (Antenna Farm). I've had excellent results with the 1/4 on both my Jeep and my SxS (with an 8" square x 1/4 thick aluminum mounted to the steel kayak rack). 50 miles to repeater easily with NMO on my XJ with it's long, wide, steel roof. I have phantom antennas that worked fine but no direct comparison for range or Q of signal. There is a difference in beam pattern and maybe someone else can explain that better than I. I'm in the high desert with tall mountains (western mountains..lol), huge valleys and a lot of open ground. I did talk to my wife at home from 16 miles LOS on simplex, from very slightly higher elevation than my house.. correction: my wife was listening to the trail group while were cruising and quoted some of the conversation when I got home. Is the Blazer a fiberglass roof? If so you would need something to create a ground plane for a permanent mount NMO. I've considered whether a 12" square of aluminum or screen material might work if mounted inside the cap and grounded to the chassis with the NMO through the metal. Maybe someone else will chime in. Of course, if the Blazer has a steel roof, it's moot, and you can use simple NMO with the antenna of choice. I was going to try a longer 5/8 wave antenna but I really don't see where it would improve much for me and would make overhead clearance an even bigger issue. But they do come in spring-loaded base.

Duct Seal, aka: bear shixx has worked for 2 years on the NMO exposed underside on my S x S. For instance: https://www.lowes.com/pd/Gardner-Bender-Duct-Seal-Compound-5-lb-Pugs/5001428173

Simple Larsen 1/4 wave @ 7" or phantom @ 3.5". Easy enough to unscrew and cap when clearance is an issue. Good coverage. Sent from my Pixel 4a using Tapatalk

I have alkaline packs for my both my 805G and my Kenwood 3170, neither run the radio. Odd screen error codes on the Kenwood, can't remember with the Wouxun but it wouldn't operate. Safe to say, I'm done with them. Battery eliminator for the 805 works fine but I rarely use it now that I have mobiles in my XJ and X4.

Got it. From my former co-worker. Had them laying all over the place. Power supply works great to power the mobiles for programming.