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Old December 8th 08, 09:02 AM posted to rec.radio.amateur.antenna,rec.radio.amateur.homebrew
John Smith John Smith is offline
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First recorded activity by RadioBanter: Nov 2006
Posts: 2,915
Default Antenna dimensions?

SparkyGuy wrote:
I believe I tried lengths of a 3% to 5% shorter length with the
director, than the drive element (i.e., the one in front of the
reflector), settling on a 4% shorter length ...


So about 26.8mm square?

With a spacing between driven element and director of ~0.2
wavelength, center-to-center.


So the director should be 25 mm forward (toward the uwave source) of the
driven element? (3e8 / 2.4e9) x 0.2 = ~25mm

Do these numbers look right?

Thanks.


My elements are made from #14 bare copper wire. It is difficult to
measure each side, individually, when constructing the antenna. Better
to cut the wire to 1 wavelength, then make your bends forming it into a
square. Of course, every attempt possible should be made to keep each
side 1/4 of this length, exactly.

In measuring the one before me, which I constructed, this total length,
about the quad, is ~12.5cm.

However, here is a calculator I referenced in my constructions:

It is a java application, you must have java on your computer. Let me
know if you can't access it and I will give you the figures it spits
out, 2.4ghz = 2400mhz. Just let me know what wifi channel you wish to
center on (frequency.)

Regards,
JS