Quarter-wave FM Omnidirectional Antenna

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madjack
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Quarter-wave FM Omnidirectional Antenna

Post by madjack »

Anyone using this antenna?
http://www.fmdxantenna.com/quarterwavetuner.html
Is it anygood? Its relatively cheap.
I am new to the hobby and just trying to transmit from my PC to the neighborhood.
What is the difference between 1/4 and 5/8 wave as far as broadcasting is concerned?
DrSandi
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Re: Quarter-wave FM Omnidirectional Antenna

Post by DrSandi »

What is the difference between 1/4 and 5/8 wave as far as broadcasting is concerned?[/quote]

5/8 wave vertical antennas concentrate more power toward the horizon than 1/4 wave. An optimized 5/8 wave antenna can give you as much double the signal strength at the receive location.

When used in AM broadcasting, a 5/8 wave is known as a no-fade antenna because it has minimal skywave at high elevations, meaning the station's skywave doesn't come back down 60-100 miles away and interfere with the groundwave. The same thing that reduces the skywave focuses the energy toward the horizon instead of the sky, which is what you want with FM. Unless you're on the bottom of a valley and want to catch the surrounding hillsides.


Dr. Sandi
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