Rotatable Dipole - Gamma Match

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W8FCD
Posts: 17
Joined: Sat Sep 23, 2006 11:44 pm

Rotatable Dipole - Gamma Match

Post by W8FCD » Wed Jan 13, 2016 10:24 pm

I have a 4-element, 15 mtr. Cushcraft yagi that was recently taken down because of space limitation. I would, however, like to use the driven element only as a rotatable dipole on 15 mtrs. Since it utilizes a gamma match I'm wondering if I will encounter any tuning difficulty. Your thoughts and suggestions are welcomed.

k9yli
Posts: 222
Joined: Fri Aug 12, 2005 11:35 pm
Location: northwest wisconsin

Re: Rotatable Dipole - Gamma Match

Post by k9yli » Fri Jan 15, 2016 3:41 pm

maybe slightly as there is now less meatal around it but it should be not an issue..

Just try it.. set it in a wooden step ladder and test it out..
or hanng from some trees with string to test..

W8FCD
Posts: 17
Joined: Sat Sep 23, 2006 11:44 pm

Re: Rotatable Dipole - Gamma Match

Post by W8FCD » Fri Jan 15, 2016 10:40 pm

Good thought - - I can place the ladder on the deck for some added height during testing.
Thanks,
73, Steve W8FCD

KC7I
Posts: 10
Joined: Mon Aug 13, 2012 7:16 pm

Re: Rotatable Dipole - Gamma Match

Post by KC7I » Sun Jan 24, 2016 7:28 am

The match will be set to the antennas impedance, usually 10-20 ohms or so. Using it directly will get you pretty high vswr.
You might be able to adjust it to work for you. Adjust the sleeve in and out, and separately the clamp where it attaches to the element.
You may need to shorten or lengthen the antenna a bit to get it to work too.

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