Tad Danley wrote:
One final question about the 4:1 balun:
Assuming a single band Delta Loop with a feed point impedance of approx
100 ohms, with or without a 4:1 balun you have approximately a 2:1 SWR -
so why use the balun?
The resonant feedpoint impedance of a loop is often a
little higher than 100 ohms, e.g. 115 ohms according to
EZNEC, in which case a 4:1 balun will lower the SWR -
sometimes alleviating foldback problems.
--
73, Cecil
http://www.w5dxp.com