Re: Log periodic antenna design

Hi Guys

I just noticed you guys talking about impedance of yagi and LPDA tv
antennas, I've used a program QY4, I found on the web, and designed a
5 director uhf-band yagi around a center frequency of 636mhz. i used
1/2" copper tubing for the directors, driver and reflector, attached
on a 1/4" threaded rod, ofcourse the driver is split to allow the
terminals, then i added 4 copper 90s to complete a folded dipole.

I am interested in figuring out the impedance as well bridging a 1
director vhf-band yagi around 168mhz also using a folded dipole
driver?
Would a multimeter or a 20khz oscilliscope help in tweaking the
antenna's impedance?

Also we have had very interesting results using a paper towel roll and
a peice of 22awg wire as a folded dipole.




.

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