I'm trying to calculate dipole lengths, and I need the calc for wavelength. isn't it 186000(light speed)/frequency?

 

yes...but that will give you the antenna length in miles.

A better rule of thumb

1/2 wave dipole= 468/frequency(MHz)

ERic

 

Is the lag included in that number? I thought there was a 95% (or so) difference in the speed of light in a vacumn vs. a wire.

 

Maybe closer to 96%. The antenna should be 4% shorter (I seem to recall) than the math indicates.

 

Or you can do 300/f (in MHz), to find the distance in meters. Yes you are correct, I'm not sure what percentage it really is but we tend to use an antenna analyzer to read the SWR and impedance of the antenna and then usually clip the ends a bit to adjust it.

 

Is the lag included in that number? I thought there was a 95% (or so) difference in the speed of light in a vacumn vs. a wire.

yes it is.....in free space it woud be 492

eric

 

Awsome! thanks!