I've heard that "rubber duck" antennas shouldn't be used inside an automobile. What is the reason for this, and are there any other types of antennas that shouldn't be used inside a vehicle?
From test pool question: T9A07
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Sign up to join this communityI've heard that "rubber duck" antennas shouldn't be used inside an automobile. What is the reason for this, and are there any other types of antennas that shouldn't be used inside a vehicle?
From test pool question: T9A07
There's nothing particularly wrong with them. Cars, being mostly made of metal, do a pretty good job of shielding any RF signals, which is why you probably get worse reception when your HT is in your car. It doesn't help that rubber duck antennas aren't that good to start with - they are "electrically short", meaning that they are shorter than a true quarter wavelength, and they are monopoles, meaning that there is no "counterpoise" or "ground return" like in a dipole antenna.
Rubber duck antennas just perform worse than an ideal antenna, especially in a car. But that said, that hasn't stopped me from using my Wouxun with a rubber duck from inside my car, or a Motorola HT from inside an ambulance without any problems. Nothing terribly bad will happen, it's just not as good as using a real mobile radio with a real mobile antenna mounted to the roof of your car.