Most people are familar with the center fed, half
wave dipoles and inverted vees that are so very popular. But did you know
that there really is no exact formula for computing the length of these
antennas? The problem is that there are several factors that affect the
resonant frequency of any antenna (including these two types.) Some of
these factors are:the height above ground, the diameter of the wire, nearby
structures, the affects of other antennas in the area and even the conductivity
of the soil.
If you've ever played around with some of the antenna
design programs you may realize that the formula for these types of antennas
vary from about 145 / f Mhz to 149 / f MHz depending on the band and the
height above ground!
Fortunately there is a standard formula that can
be used as a starting point in your design. For a center fed, wire dipole,
this formula is 142.6464 / frequency in megahertz. Although, at my location
I've Always have had to shorten the antenna in order to obtain a
At least in theory, an inverted vee should be about 5%
shorter than a dipole at the same frequency.
This page uses the standard formula, 142.6464 / f MHz
to calculate dipole lengths. You may change this number if you feel you
know a better number to use as a starting point.
Enter the formula for the antenna calculation
smaller for the Inverted Vee
Your dipole's total length is meters
Each leg of the dipole is meters
Your Inverted Vee's total length is meters
Each leg of the Inverted Vee is meters