½ wave dipole antenna

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EricExtreme

½ wave dipole antenna

#409330

Post by EricExtreme »

I am erecting a ½ wave dipole. I am curious as to what height off the ground will offer optimum performance? I have a 140ft long dipole for 70cm - 160 meters amateur radio and the optimal height was over 100 feet up in the air between two trees on opposite sides of my property. What would the optimal height be for an 11 meter ½ wave dipole? Thanks!
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#409331

Post by 295 antenna »

The way I understand it should atleast 1/2 wave length above ground level
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MDYoungblood
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#409334

Post by MDYoungblood »

A dipole can be installed at any height, the higher the better for distant, I ran one (inverted V) about 12ft off the ground with good results. The ham antenna uses a balun to compensate for irregularities, never seen one go up to the 70 cm band. Are you going to use a balun ?

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#409355

Post by 443 Arizona »

i had amazing results at just 20', had experimented with 4 balun's,
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#410122

Post by JAFO »

A Balun shouldn't be required if you wrap a decent 5T x 4.25" coax choke just below the feed point and maybe raise the ends up at about a 25°angle above the feed point level to help get closer to a 1:1 SWR.
- I like a full wavelength height above real ground at the feed point for excellent performance.
Don't forget to shorten both sides of the dipole about 5% off of a full 1/4 wave length of 108"
due to "End Effect".
If the most important part of a station is the Antenna then why do so many people spend thousand$ on equipment but only hundred$ on their Antenna system?
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