Thread: A short 160M antenna - folded elements
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Old November 8th 14, 02:26 PM posted to rec.radio.amateur.antenna
John S John S is offline
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Default A short 160M antenna - folded elements
On 11/7/2014 12:58 PM, wrote:
 wrote:

snip

The only downside to this antenna is that it is extremely narrow
banded, only about a kHz or so.

snip

I realized I should expand on that.

With all 5 inductors the same value the 5:1 bandwidth is about 500 Hz.

By staggering the values of the inductors in the four legs the bandwidth
can be improved by a little bit.

The best I could accomplish was about 1 Khz by making the leg values
.96, .98, 1.02, and 1.04 times the central leg value.

Going beyond a step factor of .02 made little difference in the bandwidth
and the resonant frequency SWR started to increase.

Okay, but the starting target was to be able to feed a short antenna
with good efficiency and I think you hit that target. I know you want to
keep it as practical as possible, but I am impressed with your results.

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