[Antennas] radial lengths for 102 inch cb whip antenna

Mon Aug 30 19:05:17 EDT 2010

> I am mounting a 102 inch cb whip on a building and would
> like to add 
> some radials to improve performance. Could someone provide me the
> calculation(s) I could use to determine the optimal length for the
> radials?
>It is not a bad idea to measure the whip and make sure it really is 102" (assuming you intend 
to use it for CB)
Many whips have been getting made shorter for use with springs, quick disconnects, ect
As you are attempting to make a 1/4 wave groundplane, radials should be the same length 
as the whip and tilted down to get a 50 ohm match at the feed 
I have made 1/4 wave groundplanes for 10, 12, and CB from 4 whips that have worked as 
well as they can....sometimes a little trimming for 10, a little added for 12
Mel
N7OKL