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Old December 9th 07, 01:27 PM posted to rec.radio.amateur.antenna
Keith Dysart[_2_] Keith Dysart[_2_] is offline
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First recorded activity by RadioBanter: May 2007
Posts: 492
Default Please perform my experiment for yourself

On Dec 9, 1:24 am, Cecil Moore wrote:
Keith Dysart wrote:
How is it that this exhibits transmission line behaviour?


The equation for a single-wire transmission line over
ground is well known to be Z0 = 138*log(4D/d)


Ahh. So the coil and the ground plane make the transmission
line, and the two terminals are between the coil and the
ground plane.

But I did not see D or d in the spreadsheet which computed
Z0.

How did you route this wire?


I used an aluminum ground plane for that "wire".
Since the wire is very short at 4 MHz, I assumed
not much transmission line effects in the wire.


I'd expect that repeatability will require the same
orientation of the coil with respect to the ground
plane. And the same height.

Of course this horizontal coil has a completely
different relationship to the ground than it would
when installed vertically in an antenna? Will the
results of the measurement be at all
applicable?

....Keith