Steve Stone wrote:
Anyone build there own antenna? Any photos ?

I use #14 solid copper wire, made into an inverted V dipole,
each leg cut to 1 & 1/4 wavelengths. On the odd multiples
of the wave, vswr's should be a flat match if cut accurately
for the frequencies of operation, so at 27.185 ~ the length
of each leg will be 516 and 1/2 inches. The formula for accurate
cuts is 234 / frequency (27.185)= 103.29 inches X 5 (1/4 wave lengths)
= 516 & 1/2 inches.

A dead flat match will be 48 to 52 ohms, an vswr of 1.3 to 1 gives the
antenna impedance of 70 ohms. You can feed this antenna with a 50 ohm
coax, but within 8 feet of the antenna you must coil 10 turns of coax
with a radius of 6 inches, and the same on the other end within 8
feet of the radio. This cancels any standing waves on the coax, as the
coax itself acts as a 3rd leg of the antenna and has the tendency to radiate
signal before it reaches the antenna !


Rod, kc0oeb