Coaxial Collinear (CoCo) Antenna - Hyps & Facts.

[abcd567]

@omiez

Hello Friends

Could someone tell me how long must each element bee if i use RG6 to do the elements and how much elements i have to do so that the antenna works fine and if i have to use a resistor at the top or is it no necessary?

Link me a ready project if you have some build with RG6.

Thanks

@Devonian

If you read these and many other articles on the internet, most have failed to make an adequately performing CoCo antenna with proven advantages over a standard 1/4 wave ground plane (spider).

Build yourself a quarter wave ground plane first and record the results you get from it over at least one week.
Without a ‘reference’ antenna, you won’t know if the next antenna you build that claims high gain is really working better or not.

Nigel

(1) I fully agree with views of Devonian (Nigel). You should fist make a 1/4 wave groundplane antenna and establish your system by running it for at least few days (or better few weeks), before attempting to make a Coco.

Please see this thread for how to make a 1/4 wavelength groundplane antenna (Spider or Cantenna):

Three Easy DIY Antennas for Beginners

(2) One of the most important thing in making a Coco is to accurately know the Velocity Factor (VF) of the coax used for making the Coco. This can be achieved by using a Coax of known brand & model whose Specs or Data Sheet is avaiilable on internet, from which you can find exact value of VF.

Once you know VF, the length of element is simply 138 mm x VF. For example if your RG6 coax has a VF of 0.85, then its element length will be 138 x 0.85 = 117 mm.