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Old September 16th 07, 06:45 PM posted to rec.radio.amateur.antenna,alt.internet.wireless
mike mike is offline
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First recorded activity by RadioBanter: Jul 2007
Posts: 9
Default Understanding Yagi antenna


"Richard Clark" wrote in message
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On Fri, 14 Sep 2007 16:17:42 -0500, "amdx" wrote:

I think this
moon cut effectively make the gap look larger.


Hi Mike,

It is simply a function of the mechanical connection of the line at
that point (the inner conductor needs the cut-out and the shield has a
closer point of attachment).

So now what can the group tell me about;
Driven element impedance


50 Ohms.

the gap


the distance between the closest points of contact before the line was
installed - i.e. the thickness of the inner conductor's insulation
(true for absolutely every antenna built).


I had to go back and look at the picture, but that's interesting, the
cutout
makes for a good fit for the mechanical connection to the coax.
And I'll use that,
"i.e. the thickness of the inner conductor's insulation"

for the gap in the antenna I'm building.
Thanks


coax length impedance transformation


Not sure that matters if in fact it has been designed to be a Z
transformer. If so, then you have one of several dimensions possible
n/4 wavelength or n/2 wavelength where n is odd.

the 4 toroids


Decoupling.

73's
Richard Clark, KB7QHC