Antenna mount question
 

Anybody used the Quadratec stainless steel fender mount like the one in the pic below? If so have you had any serious issues with it interfering with the factory radio antenna on the other side of the cowl?? Was curious who's running this setup and their opinions of mounting my antenna there...thx in advance

Don't have that mount, but my antenna mounted in that location.
Works pretty well there.

Excellent! You don't get any interference with the stock fm antenna location? I've read and done a little research that if its mounted too close it can cause a little RF inside the jeep and you can hear it thru your speakers. I'm a CB newb and want to make sure I'm putting my money to good use. That mount is a little expensive but it does come with the coax mounts and light weight Firestik antenna so that's a plus I guess...

Be sure that mount is grounded really good, run a ground wire to one of the mounting screws.

I have my two meter ham radio antenna there. Great mount. The spare tire location is horrible. Stay away from that area.

Okay thx folks for the suggestions looks like I'll keep it near the hood when I'm ready to install

It is about the worst possible place on the Jeep, isn't it? However, it is the best possible place on the Jeep if you drive through narrow ways with lots of brush, because beating up your antenna until it doesn't work is worse than have high SWR limiting your radio to a half mile out or so--at least for what I routinely do with my Jeep.

10:14 if not forwarded automatically ...

https://youtu.be/49D7YupyDBY?t=614

Uh yeah it's getting a little tight Haha, to say the least.

PS> It does go to 10:14, great video as always Mark. :thumbsup:

I always heard the spare tire location is horrible, but it seemed to be the most logical mounting location for me. My highest SWR on the channel spectrum is only 1.8:1.

For a CB, just leave it there. Make sure the mounting point is isolated properly from the antenna. I had a reading of about 3 initially. I drilled out the mounting point hole a bit to give additional clearance and the SWR went to 1.1.

I have a similar antenna mount to the hood on the drivers side, and also have a rear antenna mount elevated above the tire.

As far as reception goes, the mount on the hood is the best.

I grounded my mount to an existing grounding bolt inside the engine compartment close to where the mount is. I had to leave extra length in the wires to the antenna and ground under the hood to allow the hood to be lifted up without stretching the wires.

BTW, my mount is more complicated since it mounts to the hood itself with set screws against spacers. That's why I ran a ground wire. I have taken it off so I don't get an unfaded patch of paint underneath it and now use the rear antennas and that works fine. But, the reception was better with the hood mount.

Attachment 640012

How's the signal strength? I'm new to the hobby, have a 2m mobile unit installed, however have yet finish the job due to not being able to decide on an antenna. I would prefer something shorter, but some the guys in my local club are suggesting something around the 40" mark. So I'm curious as to how the ~18" antenna does.

I don't have any numbers but the signal strength was great - using it on a group run to talk to others in the group. I haven't tried to use it to access a repeater at long distance.

I made a 5 hole antenna mount just forward of that position, aligned with the 'windshield' loop on the hood. It works perfectly. As far as navigating narrow trails with brush the answer, for me at least, was a foldover antenna. Even strapped to the loop in the middle of the hood it does pretty good. While theoretically it's not ideal it works rather well. It also works for daily commute which include entering covered parking but allow for a fullsize antenna.

So I'm a little unclear as to the grounding need... does the mount need to be grounded or the actual antenna? I use the spare tire mount on my JK with a 4" Firestik II. I have a ground wire ran from the base of the antenna stud to a bolt in the body of the jeep. I read that the tailgate is not adequate due to plastic bushing in the hinges... Sorry to be so elementary but could really use some help. My over size tire also is in contact with the antenna on the lower portion but the antenna is rubber coated.

Thanks for any advice!

You should just follow the directions that are on the website for installation. Grounding of most antennas is very important. HOWEVER, it looks like the antenna the OP is referring to is not an antenna that requires a ground plane. Cape34, your antenna is a Firestick II. It does require a groundplane.

All antennas require some type of counterpoise of ground for them to work. The counterpoise can be the grounded fender of the body of the vehicle, or it can be the coax cable (not optimal). For the Quadratec fender mount antenna, it says that it is custom wound and the cable is of a specific length and the cable should not be coiled. This tells me that it is a NGP No Ground Plane antenna. The Firestick II says on the webiste. "These are ground-plane dependent antennas. They require a metalic counterpoise to perform properly."

Thx for all the help. Moved the ground. Was getting SWR 3+ now I'm 1.1-1.2...

Question for the CB gurus.

Backstory first.

In our club 4 of us purchased the Cobra 75 in a group buy. We also purchased 18' coax and 5' Wilson fiberglass antennas mounted with Rugged Ridge tailgate mounts with extra ground wire. All these radios were set up and checked with SWR meter. Mine for instance is at 1.0 and 1.1 at 1 and 40.. Reception is so pathetic we hardly use them. GMRS even works better so we all carry Walky's. We are totally line of site and even at 1/2 mile seeing others we cannot communicate. We were told that up north here there is so much interference that even truck drivers no longer use CB.
So we have gone to VHF with a dedicated Jeep Chanel (and logging truck channels) that allow us to communicate up to 25klm without the use of repeater service.

So the question is: If I am getting SWR readings of 1.0 and 1.1 @ channel 1 and 40. Why do I get pathetic reception? Your opinions please.

I understand the whole ground plane idea but one would think that with the vehicle ground plane being infront of the antenna the radio should receive and project a signal strongly forward.
Many years ago I use to always have rear trunk lid or rear bumper mounted antennas that worked fine. I have been out of the CB loop for about 20years.

I just used my Yeasu FT-8800R mobile in my Rubicon with the ham antenna located in the rear on an Arizona Rocky Roads mount that brings the antenna above the spare tire. The receiving and transmitting signals were VERY strong through different repeaters up to 30 miles away with me at several different locations.

I even used my handheld Yaesu VX-5R walking around with the same repeaters up to 30 miles away. I received and monitored very well. My transmission was a little weak but legible, even with the OEM little antenna. And the battery lasted fine for the 2 days I was out.

I didn't use my CB and did not have my CB antenna on the other Arizona Rocky Roads mount.

one thing to consider is the amount natural interference within the band that can exist at your latitude. It results in a higher noise floor thereby reducing signal to noise ratio.

Secondly, the Cobra 75 is a very poor radio in my opinion. I bought one because I was in a hurry preparing for a trip with friends. it was in stock locally, and it looked cool to have the small form factor. SWR was good, the radio just suffered from poor transmission, reception and bad audio quality for both tx/rx. I also had a nice Cobra external speaker to help with receive audio clarity. It was better than the small speaker in the mic but could not make up for the bad rx. I had the chance to switch vehicles during the trip and used regular, non-compact, Uniden and Cobra radios. it was clear that the Cobra 75 performance was significantly inferior.

I did did more research after I got back home and learned the transmit amp is in the mic handset, not in that little box with power and coax connections. Had I known that beforehand, I would not have bought it. Having the RF being transmitted through the curly mic cable is fundamentally a poor design. I'm a telecom engineer by trade and an Extra class ham. I won't claim to know everything, but I'm fairly well versed in this area. I replaced the 75 with a Uniden 520xl that cost cost roughly half as much and it does great. The difference was dramatic. Same coax, mount and antenna.

Im sure someone will chime in about their success with the unit, but mine is in a closet somewhere. I would give it away but would feel bad giving someone the problems that go with it. It beats no radio at all and might be useful in a zombie apocalypse if it is all I had. For a jeep, I encourage folks to skip this radio and find a place to mount a small regular CB.

Thank you .. I will look into a Uniden.

I just installed the Uniden 520XL with a 4" tunable firestick and am getting 1.1-1.2 SWR. After relocating the ground btw.
So far I have been pleased. It is on a spare tire mount as well. Eventually I may move it but for now it does what I need it to.

I'm not pushing Uniden particularly, though I've seen the 510/520 do well for lots of folks as a simple basic CB.

I do miss the NOAA weather radio function the 75 has, I can be a bit of a weather junkie. That was handy a few times when I was outside smartphone data coverage. Though I have other gear to receive NOAA, I did find it handy being included in the CB. I think Canada has a similar / comparable weather radio system.

Good luck with your choice.

With a good ground and low SWR, I'd leave it alone and just use it. If you are really into tweaking things and just want to experiment, by all means, tinker with it.

I save my real RF tweaking for my ham stuff. CB is too long of a wavelength for a truly optimal mobile installations that you can drive on city streets :)

👍 Sounds good.

I've got a 10 year old Uniden pro510XL CB with the Arizona Rocky Roads rear mount bringing the antenna above the spare tire. It's been great.

I used my comet hood mount the other day and was also able to reach the same ham repeaters 30 miles away. The responder said it was a little weaker than my rear Arizona Rocky Roads mount and a little static but very readable. A friend suggested a better ground, so I'll be installing a fender mount that mounts to the fender bolt a little further forward which will be an excellent ground. We'll see if that makes a difference.

I just installed this mount, and here's a tip.
There is a +\- 1 1/2" diameter hole with the rear window washer hose going through a rubber gromet, it's in the picture provided with the mount install instructions.
It won't fit the "to radio" connection of the antenna wire, but if you unhook the "to antenna" end, (it ships with the wire attached), the wire can be fished up and through the hole, then just slit the grommet to accept the wire.
I fished a boot lace to the area near the clutch pedal and pulled the "to antenna" end up. I then ran the wire under the carpet over to the middle of the interior.
No drilling was required, and the grommet went back in nicely.
I imagine that even if you don't have a hard top the grommet will be there.