1/4 wave or 1/2 wave yagi?

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217

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Questions from a newbie. I am new to building antennas. I built a 4 element yagi beam using N3DNO's Antenna calculator for 161.000 Mhz. It is my understanding I built a 1/4 wave antenna. I live near Charlotte NC and sometimes pick up KHB-31 NOAA station in Wilmington NC over 150 miles away. My question is , would a 1/2 wave be better in receiving this station? My elevation and antenna height is almost the same or just a tad higher than KHB-31's antenna tower height. I have added a fourth director to my antenna and it helped some. Would i see a difference with a 1/2 wave or would I be better off adding more directors to my 1/4 wave?
I have included a pic of my creation. Someday I will replace the cardboard tube with some pvc and the all the elements will be the same material so it can be left outside. Also found a good use for a unwanted telescope.
 

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KC0QNB

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If you used a yagi calculator the driven element, is probably a 1/2 wave dipole (1/4 wave on each side).
How long is the driven element, tip to tip both sides?
 

k9rzz

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Usually the directors are approx 5% shorter than the driven element, and the reflector 5% longer. (1.7 inches for 162mhz ). Your elements look alot different from the driven than 1.7 inches. Sounds like it's working, but you may get it to work even better!

Here's the NOAA antenna project I did quite a while ago, it worked GREAT !!

http://www.radioreference.com/forums/showthread.php?t=46494&highlight=noaa+yagi
 

KC0QNB

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Half wave driven element, one thing to try is a multi element quad, I built one a few years ago to receive a distant NWR transmitter, worked like a champ! and simple. I don't use it anymore because the NMS installed a closer relay transmitter.
 

zz0468

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Something doesn't look right. The driven element is way too large in comparison to the rest of the elements. The reflector should be the largest, then the driven element. The directors would get progressively smaller than the driven element.
 

217

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zz0468 there is a fiberglass whip running through the driven to keep them straight. That is why it looks like the driven is longer than the directors. This was just thrown together in a matter of a few hours. Hopefully the finished product will look better than this.
Thanks for clearing that up for me KC0QNB. I was just a little confused about that.
I thought about a quad. I have some 10 gauge solid copper wire, enough to make maybe 7 elements.
 
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