SWR issue. Antenna probably not mounted right, definitely not factory.

[Gregory1984]

So this is born of redneck ingenuity/broke/dumb. LOL First of all, I only know just enough to really mess things up, like I just did. The magnet fell out of my old Wilson and I got the bright idea I could just zip it onto my bumper with with self tappers. It's giving me a super high SWR. So I don't know if I ruined the base somehow and need to just break down and buy a new magnet mount base for it. I also don't know if the high swr is because of the fender right next too it, don't know if it works that way. Also I read that even a magnet mount antenna needs to sit on top of metal and that part of my bumper is mostly plastic. So I wonder if that's the root cause, and if so is it just fubar in that position or could I add a ground strap back to the frame or something. Also if what would be the best strap and how/where to fix it to the Wilson.

 

[Gregory1984]

So this is born of redneck ingenuity/broke/dumb. LOL First of all, I only know just enough to really mess things up, like I just did. The magnet fell out of my old Wilson and I got the bright idea I could just zip it onto my bumper with with self tappers. It's giving me a super high SWR. So I don't know if I ruined the base somehow and need to just break down and buy a new magnet mount base for it. I also don't know if the high swr is because of the fender right next too it, don't know if it works that way. Also I read that even a magnet mount antenna needs to sit on top of metal and that part of my bumper is mostly plastic. So I wonder if that's the root cause, and if so is it just fubar in that position or could I add a ground strap back to the frame or something. Also if what would be the best strap and how/where to fix it to the Wilson.

Follow up info. So I did a lot of reading since I posted this and I can also tell you the swr curve is high and flat. Damn near dead nuts flat. So I take it what I'm experiencing is a lack of a ground plane. Plopping a "magnet mount" antenna on a plastic bumper cap seems a lot less than ideal. Wondering if you guys think I can run a ground strap from the metal that the coax ground is soldered too in the base, and run it to the frame, also maybe bond the frame and the tub together if that would get my curve to lower.

 

[mmckenna]

That ~might~ improve things, but I doubt you'll ever see low SWR. Part of the problem is having the antenna sitting so low down behind the body and the whip so close to the sheet metal.

Getting low SWR on Jeeps can be a challenge. There's some good posts on this site if you start searching where others have mostly solved this issue.

 

[Gregory1984]

I'm going to try grounding it to the frame in the next day or two. And see what happens. I don't have a proper stand alone swr meter but my cheapest radio reports somewhere between 2 and 3 swr and my galaxy99v2 shows almost exactly a 2. With that antenna back when it had a magnet, and it sat on a proper surface like the hood it had an swr so small it wouldn't move the needle on any of my radios. After reading about how magnet antennas ground them selves, and knowing it's bolted to plastic with no metal underneath, I am confident it has no grounding. I don't know how much lower the swr can get, but Im gonna try grounding it to the frame and maybe bonding the vehicle's tub (sort of majority of body) to the frame. See if that helps. I suspect it will lower it somewhat. Don't know if I can get it lowered to where I can run my Texas star linear though. I was gonna glue a 2' square piece of sheet metal into the roof and rf ground that to the rollbar and do a roof mount but it would have to go through several inches of material cause of a rib in the roof and I just kind of got lazy about figuring that out.

 

[mmckenna]

The ground plane would need to be large and be right under the magnet for it to work. Don't confuse DC ground with an RF ground plane, two different things.

I'd not waste an amplifier on that setup until you get the antenna sorted out. The antenna will make a bigger difference in performance.

 

[slowmover]

Hood

 

[slowmover]

KØBG.COM

A Web Site For Mobile Amateur Radio Operators

www.k0bg.com

Take your time, here. I’ve read & re-read and can maybe say I’ve learned some things. Can’t go wrong.

Jeeps aren’t ideal, that you already know. So a goal is required. What have others accomplished?

A model to follow is easiest route. Don’t re-invent the wheel.

IMO, on a personal vehicle 40-80W gets the job done. More just means TX farther than you can hear.

Ears have priority. Clarity in TX & RX means the most. (Hear, and Be Heard).

I’ve had a 99v2 since they came out ten years ago.. It was in adding a West Mountain Radio CLEARSPEECH DSP Speaker that my world changed: I had the best ears of anyone around me as now the hash was removed from voice.

West Mountain CLR-SPKR - Review

After reading several posts by @slowmover extolling the virtues of this speaker, I bought one and tried it today with a CB (President McKinley), ham radio (Yaesu FT-818), and scanner (Uniden BC125AT). Operation.--The speaker comes with its own power and audio cables. The power cable is...

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— Received, and spoke with those the men around me couldn’t hear.

Thus,

1). Antenna System

2). Power System

These matter.

The radio then becomes just a component we plug in. Less important.

A 1989 radio system in 2023? Naw

2023 Best Mobile CB

Via mobile experience as an OTR truck driver. Several thousand hours annual use. Earlier references to the Qixiang factory’s new circuit board elsewhere. Several brands. The above possibly the best known example at present. Paired with the equally new Driver Extreme DRX-9010 External Speaker...

forums.radioreference.com

This’ll be an easier install by the end is it’s near-greatest attribute. And will outperform the gear you mentioned given best antenna + mount location.

— I’ve jumped ahead of your first line of inquiry as it’ll be easier to plan the systems accordingly if it appeals (significantly better RX, and better RX/TX performance on Sideband).

— Keep the 99v2 + TS for home station. (And TS off of AM-9 & 19). Consider upgrade for stability:

DDS-VFO

DDS-VFO A 21st Century upgrade for the better CB transceivers of the era just past. — No more SSB drift — Scan — VFO My desire is to also add DSP to the RX side. (West Mountain hadn’t seen that on a CB, yet, and kindly offered circuit diagram advice)...

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[slowmover]

Keep looking around this site. May have to dig thru threads on other radio service types to find CB info asides.

I hate tuning CB antennas

I have a Laird C27 antenna on an NMO mount with 17 feet of RG8A/U coax. Mounting it in a 2021 Jeep Gladiator connecting to a Cobra 25. Before installing the coax in the vehicle I connected it to the NMO mount and tuned it to the radio. Got an SWR of 1.7 on 19. Installed the coax in the...

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