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somis81
03-25-2022, 05:36 PM
2535I am a newbie to CB.
Just bought a President Randy FCC handheld.
I have a Tioga 29ft RV and bolted a Firestick antenna mount to my mirror arm and put a 36" firestick FL3-B 36" Firefly antenna with a tuneable tip and a 10ft coax going through the door jamb to the handheld I checked the SWR and it's way over 3. So I checked all the antenna wiring and bracket for continuity and shorts, everything is fine and the ground is reading solid to the chassis. I tried adjusting the firestick tuneable tip all the way up and down, still same reading on all channels. The SWR reading is way over 3 and halfway into the red bar.
Any ideas?

JesseJamesDallas
03-25-2022, 07:17 PM
Mirror arm is not grounded...best-bet would be a fender mount like the other antenna you have mounted by the stereo antenna...

somis81
03-25-2022, 07:27 PM
I checked the steel mirror arm from the antenna mount to the battery and the chassis with a ohm meter and the ground from the antenna mount to the battery and chassis is rock solid.

Alabama Buckeye
03-25-2022, 10:38 PM
What is the travel lodge made of? Aluminum, sheet metal? Check continuity between mounting screws and batt. grnd.
Check continuity radio case to ground.

Nice catch there JJ on the loaded antenna base.

Alabama Buckeye
03-26-2022, 09:47 AM
Truckers have a habit of supplementing their mirror mounted antenna bases with auxiliary dedicated grounding straps from the bases to an under hood grounding bolts. Why? Because the weak links between the mirrors mounts and a positive ground. Movable/Swivel mirror brackets make for P1$$ poor ground contact.

Not to mention the likely reflective nature of the travel lodge you're toting. Jessie James recommended fender mounting. I'm doubtful your 3' Firestik will do much better there.

A cursory look look at the Randy FCC, reveals cute HT radio. They have their place. RF power out, Check! No mention of 4W legal power. Did your SWR check reveal any insight as to how much RF power?

You may be better off with the included Rubber Ducky antenna. Glass is not a barrier to radio signal. You'd have a 180 degree forward cast of radio signal. Of cource you want to hold it vertical.

There's no telling the mangled status of shielding as it is passed through from outside cab to inside.

#1 Number One importance is antenna. And yours is in the running...See https://www.peopleofwalmart.com/

(https://www.peopleofwalmart.com/)

somis81
03-26-2022, 01:46 PM
JJ, Buckeye, thanks for the help, the REF is reading 7%. I have the handheld on 4 watt hi power. The president randy has great reviews with no complaints about power.
I grounded the antenna base to the engine compartment battery grounding bolt with a spare battery cable, still no luck, still way over 3 SWR. My motorhome is aluminum and the antenna may be too close to the body and mirror or maybe it's the wrong kind of antenna.
I can hear truckers talking on channel 19 with the Firestick, but the rubber ducky doesn't pick up anything.
Not sure what to try next.

Alabama Buckeye
03-26-2022, 03:28 PM
7% bad. Think magnetic mount.

You got a chance with magnetic mount antenna. 3'er Firestik can be a component but won't work as mounted.

Must be on top. A steel base attached to aluminum chateau grounded adequately.

7% ya got me there! That's not 7% of 4Watts. That's off the charts, somewhere between totally undesirable and infinity.

JesseJamesDallas
03-26-2022, 04:30 PM
For a example of what I was getting at...On my old work van I had similar mirror arms as what you have, and as much as I tried to mount a antenna to them, with all the extra grounding I tried, just like you my SWR was up over 3...

Finally decided on mounting to the front fender, and fab'ed-up my own fender mount...Once done, SWR was flat as a pancake...

Now as Alabama pointed out, it would be better if the antenna was a bit taller to get above the roof line of the camper, but I think the one you have will still work fine if you move it to the drivers side, and fender mount it...

Here's a pic of my old work van...sorta hard to tell how tall the antenna is in the pic, but it's little over 5' (looks taller in the pic)


https://i.imgur.com/cry03lg.jpg

whiteastro
03-26-2022, 04:51 PM
You gotta get that antenna above the roof line so it can see and breath !

Alabama Buckeye
03-26-2022, 05:51 PM
Steel disk mounted to top of camper.

I've had enough of this. Last post! Fix the GD site server.

Somis81, you need a mag mount antenna on top.

Gone.

somis81
03-26-2022, 08:21 PM
JJ, I will make a L bracket and install it on the fender tomorrow, will let you know how it went.

JesseJamesDallas
03-26-2022, 09:02 PM
You gotta get that antenna above the roof line so it can see and breath !
Technically about a foot of his antenna would be "above the roof line" mounting it on the fender like I was talking about.

The body of that RV is fiberglass and composite stuff and not metal, so the antenna won't even really see it...Plus by moving the antenna forward to the fender will get it away from the cab which is metal...

I do agree mounting to the roof would be a better location, but not realistic in this case...from ground to top of the roof is probably 10' or close to it, add a antenna to the top of that, and it would be history first bridge you drove under.

Buff
03-27-2022, 01:45 PM
Did you try tilting it forward on a angle? We put antennas on my buddies dump truck mirrors we had to tilt them forward for good SWRS.

somis81
03-27-2022, 03:59 PM
Bingo JJD, you nailed it!
I would never have thought the mirror arm wouldn't work since it showed good ground.
I made a temporary bracket this morning on the drivers side fender, changed the antenna over to it and what a difference it made. I am showing SWR hovering around or below 1 on all channels.
Thanks a lot.
I just ordered a fender mount from Alexa, now that the SWR problem is fixed am thinking of changing out the 3ft stick for a 4ft stick. The problem is that the roof overhangs the hood, and I don't want the antenna hitting the overhang.
I think I will drive it a bit with the 3ft, see how it sways first.
Thanks again, really appreciate it!2536

JesseJamesDallas
03-27-2022, 07:10 PM
Bingo JJD, you nailed it!
I would never have thought the mirror arm wouldn't work since it showed good ground.
I made a temporary bracket this morning on the drivers side fender, changed the antenna over to it and what a difference it made. I am showing SWR hovering around or below 1 on all channels.
Thanks a lot.
I just ordered a fender mount from Alexa, now that the SWR problem is fixed am thinking of changing out the 3ft stick for a 4ft stick. The problem is that the roof overhangs the hood, and I don't want the antenna hitting the overhang.
I think I will drive it a bit with the 3ft, see how it sways first.
Thanks again, really appreciate it!2536
Yep, like I said, I went threw the same thing on that box van I had, and although the arms "seem" to have good ground, they just don't like cb antennas!:300 (97):

4' antenna would be better than the 3' sure, as long as you can keep it from hitting the over hang...

Glad it worked out for ya...Might be a bit more sturdy if you could figure out a way to mount it to one of those bolts I see in the picture also.

Alabama Buckeye
03-27-2022, 11:47 PM
Giving the site another go with MacBook in lieu of Windoze.
Somis led us to believe chateau was aluminum leading one to think of blocking shadow. If so, the right rear will not receive transmissions.

Can't speak with experience as to height of usual 18 wheelers and bridge clearances. Some small town RxR overpasses have taken the lid off a share of trailers. Google search sez 13.5' avg hit for semi-trailer. Certainly the usual KOA campgrounds aren't adapted to tractor trailer traffic.

I should attempt writing an epistle here just to see if server takes a dump on me. But, I retire instead.

Glad you got a fix on it Somis. You might give some thought to one of those medium SS springs for the antenna. 3-4" hgt with straight vertical sides to them, versus 6" HD model with the bulging beer belly. Less stress on fender and mount should you encounter a brush up. Must add: 5' Firestik and 3-4" spring - no good. Antenna will suffer Peyronies disorder in no time.