Benefits of a spring under a Firestik?

[trip6ram]

I was wondering if there is any benefit to using a spring between the antenna (4') and the fender mount, aside from the obvious (flexibility if/when hitting stuff). I honestly can see that being the biggest plus, but want to "ask the experts" just to be sure.

[TheCBDoctor]

I was wondering if there is any benefit to using a spring between the antenna and the fender mount, aside from the obvious (flexibility if/when hitting stuff). I honestly can see that being the biggest plus, but want to "ask the experts" just to be sure.

Hi,

Sometimes a spring will mess with your SWR. The shorter the antenna the more likely the spring will affect the antenna's performance.

Just my humble observation.

['Doc]

You're right about that spring, it's only benefit is that it is 'springy', flexible. It does affect an antenna's length though, makes it longer. If the antenna is the right length to start with, adding a spring means it isn't right anymore. The typical way of correcting that is to shorten that antenna by the length of the spring.
You don't have to be an 'expert' to know that, and I'm not an expert.
- 'Doc

[trip6ram]

Figured as much.

Thanks, Dr. and Doc.