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Old September 16th 07, 05:38 PM posted to rec.radio.amateur.antenna,alt.internet.wireless
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Understanding Yagi antenna

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).

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