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Old April 2nd 07, 03:41 PM posted to rec.radio.amateur.antenna
Yuri Blanarovich Yuri Blanarovich is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 170
Default Best Yagi impedance


"art" wrote in message
oups.com...
On 17 Mar, 20:41, Owen Duffy wrote:
"Yuri Blanarovich" wrote
:

...

I realized that Yagi has low impedance and I generally do not like any
matching and introducing unnecessary loses. The way for maximum gain,
clean pattern, great F/B, 50 ohm feedpoint impedance and no matching
gizmos to me was to go Quad and Quad/Yagi element combinations. Quads
have higher impedance and by adding elements, the impedance would drop
to around 50 ohms.


Yuri, that is your approach, but it is not the only one.

Others of us quantify the expected transformation losses, and add them
into
the gain equation to deal with the effects, making a design selection on
a
rational basis rather that just excluding a whole bunch of solutions
because of a prejudice about matching loss.

Owen



Owen
I agree. Amateurs and probably some professionals place to much weight
on total antenna gain as opposed to maximum gain of the required
polarity and frankly polarity is always of primary importance for all
antennas. This rationality also include the attainment of less
required compromises with other factors when dealing with bandwidth
(per the above comments referncing matching.) Compromises with respect
to the design of yagi antennas is extensively described in most ARRL
publications and are best avoided.
Art