Anyone ever replaced the antenna and cable on a '72 coupe?

[Terry M.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Robert, I'll let you know what I find out if you'll let me know likewise. Don't know about a bad antenna wire. I had two new ones at hand and tried them both prior to installing. As I noted, AM worked fine with both cables stretched out and the antenna assembly laying on the garage floor

Just a guess here, since I am not an EE or even an E, but laying the antenna on the garage floor may not be a lot different than grabbing the antenna with your hand.

[Jack H.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Put a glove on your hand. Grab the antenna mast and note the 'problem' has evaporated!

Basically, with naked skin you're adding the intrinsic capacitance of your body to the antenna system and boosting the antenna's signal capture profile. Not unlike changing a given system from a 1/4 wavelength to a 1/2 wavelength antenna.

Of course you see no effect by touching the antenna ground plate. It's job is different. There is no direct electrical interface between the plate and the antenna. It's job is to 'emulate' a ground plane.

On a conventional car, the antenna mounts above a METAL body. The body panel provides a ground plane to reflect broadcast radio waves. So, the antenna gathers both the incident and reflected broadcast signal.

Corvette has a non-conductive fiberglass body. The body panel is basically invisible/transparent to broadcast RF. The small metal plate that mounts below the antenna serves to mimic the metallic ground plane of a conventional stamped steel bodied car and provide a reflecting surface to broadcast RF signals.

That's why you don't see much difference with or without the ground plane in a high signal strength major metro area. But, go drive out into the 'boondocks' where you're in an RF 'fringe' area and the with/without difference IS noticeable...

[Rey S.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

After reading all these replys to antenna C-3 antenna replacement I have learned one thing -- put the new cable in before I install the rigth side exhaust. Another thought about grount plane effect on the radio reception, this very similar to the ground plane situations encountered during the old days of CB radio (non truckers remember these ?) I had mounted a CB from the center Ttop bar - same reception problem - cure - run a 12/10 gauge wire from the ground plane plate to the frame of the car to increase the metalic signatue of the vehicle area. Additional "area" can be enhansed by including the exhaust system into the loop. Hope these ideas are some help!
Rey Stenhouse 26007

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Terry, you may be right. Sounds logical.

Jack, Rey, with all that said then mine should work fine assuming I have a good connection between the strap and the frame. My brother's '69 is built the same way and his works fine.

Hmmm