Why Is This?

[scanaholic]

I have a Shack Pro-433 with an antenna, I can't even recall the name of it. It is a good one, flexible but thin. A skinny type rubber duck antenna. Anyway, when there is a weak signal on it, if I walk up to the radio and put my hand at the base of the antenna, the signal nearly triples! What could I do to keep the signal that good without having to hold the bottom of the antenna? It makes me think some grounding isn't right about the antenna or radio itself.

Thanks for any input.

 

[zz0468]

You're just coupling more signal into the antenna from the proximity of your hand. There's a number of mechanisms that would do this. It's anyone's guess exactly which one is taking place.

What could I do to keep the signal that good without having to hold the bottom of the antenna?

Hire one of the neighborhood kids to hold their hand there, or maybe a better idea would be to install an outside antenna.

It makes me think some grounding isn't right about the antenna or radio itself.

You can stop thinking that. This is common. There's really no such thing as a "good rubber duck" antenna. It's just that some are worse than others.