On Fri, 26 Dec 2003 10:15:02 +0000 (UTC), "Reg Edwards"
wrote:

Assuming a roughly all-round, no-particular-direction antenna is required,
then the most simple antenna is called for. A simple antenna is also the
most efficient.

The most simple antenna is just a straight, vertical rod fed at its center
between its two halves. For F = 434 MHz, overall dipole length is crudely
0.33 metres = 13 inches.

Reg, you obviously know a thing or two about antennas. I need to come
up with a small antenna for a hand-held 40Mhz transmitter. I'd like to
use some sort of rubber duck helicoil to save space if poss. Any ideas
as to dimensions etc? The output impedance of the tx is around 140
ohms.
--

"I expect history will be kind to me, since I intend to write it."
- Winston Churchill