I have a design based on EZNEC. Total shortened "half-wave" dipole length
is 0.32 lambda. Half of that of course is in each of the two elements.
There is a loading coil in the middle of each element. EZNEC assumes zero
length, non-radiating coils. In reality, the coil length is significant
compared to the element length.



Welcome to real world. If you want to read more about the loading coil
controversy, go to my web page www.K3BU.us and snoop around ARTICLES, you will
get the picture. Eznec doesn't understand real coils, you can try to substitute
the coil with hairpin stub of the same inductance for modeling.

With 450 MHz dipole you will "research" this subject faster by taking piece of
wire or tubing, make about 3 turns in the middle, put the dipole up, measure
the resonant frequency and then snip the ends untill you get it where you want
it. Fine tuning can be done by squeezing or expanding the coil turns.

To make it more efficient, you can just bend the ends 90 deg. in L or T shape,
instead of using coils.

Yuri, K3BU.us