Ground strap composition

RedFish said

I had a GM something ( lumina maybe? I forget ) here once with strange electrical problem that turned out to be ignition switch. Anyway,,, It was previously a police cruiser. It had those braided ground straps on every hinged body part, hood, deck lid, everywhere I looked. I'm guessing tasers versus electronics was the reason for.

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Radio noise. Another thing used on two-way radio equipped cars are little sharp springy contact fingers screwed into the hood fit area. The hood presses against them and they press against the mating surface, and hopefully provide a ground.

You can HEAR this if you have an AM radio. With the car idling and tuned to a weak station or in between stations, turn up the "noise." Then slowly open the hood. You will start to hear a marked increase

'Member Corvettes? Plastic bodies? They have a metallic structure around the ignition wires to reduce radio noise.

Hood to firewall grounding for two-way radio must be as short as practical because the wavelengths are so short. A basic 1/4 wave vertical whip on 450mhz for example is only around 6". that is the equivalent of a 9 FOOT whip at CB frequencies. So a single 6" long grounding strap does little at all on UHF