trying to get a good CB ground plane

Mounted my cb antena right behind the cab with 2/3 of the antena above the roof line. Hoping the tool box will give me some ground plane reflection since our beds are not metal.

1- anyone running there antena here and how is it working for you.

2-will i need to ground the antena? It is mounted to the top fiberglass rail of the back of the bed....if I need to ground it....where should I ground it to?

 

The metal rail is grounded but you could not have picked a worse place for an antenna. The plastic bed has all most no effect and your box unless it is grounded to some thing will make things worse. Your best bet would be to put the antenna in the middle of the box, bottom line vehicles are very poor ground planes but having the antenna clear of metal objects will make a big difference.

 

That thing looks like it will slap the shit out of your rear window and roof line if you decide to go on a rocky road.

 

Yes gave it a quick test drive yesterday and seemed to be okay...didn't move around at all. I'm not running a spring so I should be okay....so how is the rear bed rail grounded? It just bolts to the fiberglass bed? The truck box is attached to the bed rails with J hooks....so if the rails are really grounded...then the box should be too. How is having the antena on top of the box and centered any better then where it is now?

 

I agree with Tim, move the antenna away from the cab.

 

OP,
How about using a "No Ground Plane" antenna?
I remember this from back-in-the-day mounting antenna on a Corvette.

http://www.rightchannelradios.com/cb-antennas/shop-by-type/no-ground-plane-cb-antennas.html

Just a thought.

 

I would steer as far away from those as possible.

 

Yeah...I'm told they are not as good...how is that rear bed rail grounded?

 

I see a lot of trucks with their antennas set up this way.....anyone else running one like that?

 

Hard to tell how long it is. You should have at least half the antenna above the roofline. I had two Firestiks one of which was a NGP. Couldn't get the SWR low enough on either one. Switched to roof mounted mag mounts years ago and never looked back.

 

I have 2/3 of the antena above the roof...I hear lots of issues with NGP Antenas as well as dual Antenas. Waiting for my SWR meter so I can hook it up and check it out...

 

Any other input?

 

There is no other way to put it, but that isn't gonna measure a good SWR in that form at all. I mounted my 4' Firestik to the passenger side of my tool box. At first it was reading an SWR of 3, which means that it isn't grounded properly. To fix that, I took a length of 10 or 12 ga wire, put a lug on each end, and bolted one through a mounting bolt for the front of the fender, and the other to one of the bolts holding my mount to my toolbox, and I quickly was able to tune the system to 1.6 or 1.7. Though it isn't perfect, I don't have a perfect system, and it works just fine for me to get weather reports 20 miles away, fwiw.

I do have a real stainless mount that my dad and I made, and I also have a barrel spring on mine, but I think if you ground it properly, it will be "ok," besides the fact that it might smack the piss out of your truck. With mine where it is, even with a "loose" barrel spring, has never came close to my truck, and it's kinda fun to watch it going everywhere.

 

+1 on the roof mount mag mount...

 

Is is not bolted to plastic it goes through it to the frame work under it.

 

Your SWR of 3:1 does not mean you have a bad ground it just means that the match is poor being too close to the body work or standing next to it during the process can cause a poor SWR reading. A poor ground can cause that but if there is any metal involved it's grounded, you do not need a 4 ought cable to create a good ground just a good contact to the metal work. Placing the antenna against the cab is a very bad plan you only have 4 watts to play with us it wisely. I get weather reports with a hand held 40 miles away it has a 6" antenna. They generally transmit from a fairly high spot with a 100 watts or more on a band that is a far higher frequency than CB their intension is to be heard.

 

A non-ground plane antenna is for plastic stuff boats etc. How they work is by creating an artificial ground the bottom half of the antenna is wound with a matching length wire to the top half creating a half wave antenna. This takes a lot of wire, 11 meters more or less and it is lossey probably more so than the so called “ground plane” of the average truck. There is a lot of science involved here and most installs work in spite of them self how well is another story.

 

I have a 2014 TRD Sport 5ft. bed and like the look of the antenna behind and in the middle of the cab but like you i could not get a low SWR reading and without a 1.5 or less you wont get out that far and if its 3 or greater it can fry the finals inside of your radio, Very costly to repair .I found that on the rear of the bed right beside the tailgate on either side is a factory black bolt and I used this bolt and a self tapping screw to secure the antenna mount to the truck. When I was done and checked the SWR again it was on 1 which is the best you can get. Don't like the looks of it back there but the performance is awesome. good luck

 

An SWR of 1.6 is not that bad!?

My understanding is that under 2 is good....

That bed rail right behind my cab is not touching steel at all. It is bolted to the Fiberglas bed. So the mount touching the metal bed rail will be ground enough?

 

Won't the antena stick up above the cab enough to not matter?