[aprssig] Scaling APRS antenna

Mike Yetsko myetsko at insydesw.com
Sat Sep 18 19:45:06 CDT 2004

> >I picked up a beam stainless steel 400-420 MHz
> >
> >How can I work out how much to cut off to bring it up to 438 MHz ?
> >
> >
> Work out by dividing 410 by 438.
> Desired length should be 0.9361 of present length.
> Remove 3.2% from each end of each element.
And don't forget that as the frequency goes up and the diameter of the 
elements approach a significant percentage of the wavelength that
affects the resonant length calculation...

More information about the aprssig mailing list