Would a Diamondback cover make a good ground plane?

I'm curious about something.

I have always wanted a 102" whip antenna for my CB in my truck. Currently I have a Wilson 1000 mag mount on top of my cab, and the SWR's are low and it transmits/receives well.

Just for nostalgic purposes, I'd like to install a whip antenna. I don't really want to install it on the bumper/rear quarter panel. And of course installing it on top of the cab would be pretty tough, as far as support would go for it (definitely would have to reinforce the inside of the roof). But as I was wondering about this, I thought why not install it on the center portion of the Diamondback bed cover that I have? Nice, rectangular ground plane of sorts, though a couple of feet lower than the cab's roof. Wouldn't really matter to a 102" antenna though.

But the Diamondback is aluminum. Is it still a good enough surface for a reflective ground plane?

 

It should be fine as long as all 3 sections if the cover are grounded to the frame.

 

If you have an SWR meter just move it and test it real quick.

 

I haven’t seen a CB whip antenna since the 80’s. I recently bought a gmrs radio because that seems to be more popular these days. I updated myself.

 

Thanks gents. Once thing I did realize after looking hard at this; the DiamondBack cover is in no way grounded at all to the body/frame of the truck. Everything rests or is clamped pretty much to plastics of the rear bed. If I do this, looks like I also will have to do some braided ground lines from the cover to the metal of the truck.

Why can't anything be simple anymore?

 

Cell phone.World has changed.

 

Nerp. I like old school. Still use my CB. Also have a cell phone.

 

How do you make a general call to a group of people nearby (that you don't know) on a cell phone? 2 different tools for 2 different purposes. Most use CBs for real-time, local sharing of information.

 

Does the diamondback make good metal contact to metal on the bed. Then it should be ok.

 

Do you ever use the bed of your truck? If you mount that whip on the center of your bed cover you won't be able to flip the cover open.

 

Tpr that's good point.

 

I'd still be able to open both covers (front and rear). The whip Antenna would mount to the narrower center panel, which doesn't move.

However as someone also noted upthread; the Diamondback cover is not grounded to the bed of the truck. I'd have to install copper mesh cable to ground it to the bed. All the current contact points of the Diamondback engage non-metallic areas.

So I am now re-thinking the whole idea of doing this. Starting to become a bit more involved.

 

This may be a dumb question but where on the bed would you ground it to since the bed is made of composite material and not metal?

 

The columns supporting the tailgate are metal.

 

Once you drill through the center panel, the underside of it is untreated aluminum.

 

Yes. But the Diamondback cover is totally insulated from the bed by its sealing gasket. And the four clamps that hold down the center panel do not ground underneath the lip of the trucks bed rail.

So I would have to introduce a ground strap to do this.

 

well, their is a little continuity without big ole ground straps. But they certainly won't hurt. As far the an effective ground plane tying the three Diamond back pieces
together would be best On my VHF/UHF antenna made by Diamond I believe, it is a radialess ground plane, basically doesn't require a ground plane. But you definetly will need one for 11 meters. They do make some really snazzy ones that can fold just haven't pursued that in years

 

Vehicles in general are poor ground planes, metal or not, your real ground plane is the ground below it. I have worked the world from my truck on HF no problems 2 meters, 1.25 and 70CM. With it's plastic bed and the antennas in it. Your metal plate will make no difference.

 

I'm not sure how you expected to do this without a ground strap.

 

The body of a vehicle is an inadequate ground plane or a bus for that matter at ham VHF-UHF frequency's. The ground of a antenna is the braded end of the coax it is the return path to the radio. Decades ago they used ground straps on old low frequency AM stuff mobile.