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Old April 7th 11, 02:57 AM posted to rec.radio.amateur.antenna
tom tom is offline
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Default 40/15M dipole question

On 4/6/2011 8:16 PM, John - KD5YI wrote:
On 4/6/2011 2:51 PM, John - KD5YI wrote:

Hey Cecil -

I got:

Impedance = 85.26 - J 186.3 ohms
SWR (50 ohm system) = 10.337 (75 ohm system) = 7.308

Let's see if we can determine why they don't match.

I adjusted the wire length for no reactance at 7.2 MHz.
I used 99 segments of #14 wire. I did not include insulation effects.

How about yours?

John


Are you using 9 segments?

John


I think may have missed something on how segmentation works. I thought
you needed an even number of segments to split a dipole evenly.

So while 99 is close to centered by my logic, if 9 was used it might
skew things a bit.

If I'm off base please tell me so I can adjust my model of how NEC works.

Thanks.

tom
K0TAR