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CB Dipole antenna

nicky

Member
May 9, 2018
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I have read about dipole antennas for 11 meter and I want to put up a horizontal dipole and someone posted about a 1/4 wave being the best for DX. I don't understand the difference between 1/4 and 1/2 wave as far as the length of the wire or tubing used . Could someone shed some light on this? Thanks much
 

dipole.jpg

Half wave overall total


 
Here is one I just bought ready made. MFJ-918
You can buy them ( Dipole ) ready made on ebay really cheap.
 
I have a wire dipole strung up with clothes line between two poles on the corners of my garage. Only about 20 feet up, it works great for DX. I also have a starduster on the same garage, I am going to put them on an antenna switch so I can easily compare the two.
Balun or no Balun? I just built one with no Balun and wondering how it will do.
 
Balun is not optional, it's mandatory.

Dipole feed with coax always need a 1:1 balun. Otherwise coax will radiate, will be also taking it's part on RX picking up local noise.
100% on this!







Take note, you're feeding a balanced antenna with an unbalanced feedline such as coax and will cause the unequal current to flow back on the coax line…hence the term "common mode current".

A 1:1 choke balun is used to control this by adding enough choking impedance to a given frequency or broadbanded to cover a much wider range.

"Ugly" air wound chokes work and are simple to make. Better ones are small coax or teflon wire wrapped around a 2 x 1/4" mix 33 (or 43 if higher bands are used more) ferrite ring or in series with 2 rings and installed in a weather proof box. Typically 2 gang electrical boxes are used with RF connections for easy install.

Think of it this way by definition, Bal-un, balanced to unbalanced.
 
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I have a wire dipole strung up with clothes line between two poles on the corners of my garage. Only about 20 feet up, it works great for DX. I also have a starduster on the same garage, I am going to put them on an antenna switch so I can easily compare the two.
I have one up in my attic and it amazed me one time with the clean quite DX I got out of it. It's hooked up to my Dosy meter with a switch that my StarDuster is on also. I'd like to get my Dipole outside also but my climbing days are slowly drawing to a close.
 

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