A six element curtain array for the CB band

Hi,
I just wanted to share my rather unusual homemade CB antenna. It covers 10 MHz to 29 Mhz, but I designed and built it with the CB band in mind. It is a six element curtain array like the shortwave broadcasters use. I could have gone the traditional yagi or quad route, but I wanted to try something different.

The antenna uses six .6 wavelength horizontal driven elements at 27.205 MHz all at the same time. The bottom two elements start at 1/2 wavelength above the ground. The second element pair is located .6 wavelengths above the first pair, and the third element pair is located .6 wavelengths above the middle element pair.

The total antenna array size is 43 feet six inches tall and 43 feet six inches wide. It is fed with three equal length sections of 450 ladder line back to a central tie in point, and then a fourth piece of 450 ohm ladder line goes from there back to a 5 killowatt 4:1 Guanella current HF balun. From the balun I use a three foot jumper back to my antenna tuner. The tuner came with a built in balun, but it was crap so I used the external balun.

I posted a YouTube video so interested parties can see this very unusual CB antenna.

My homemade 6 element curtain array antenna for the CB band
My homemade 6 element curtain array antenna for the CB band - YouTube

This video shows a receive A/B comparison between a half wave horizontal dipole and the six element curtain array;

Receive A/B test between my 1/2 wave dipole and my home made 6 element curtain array
Receive A/B test between my 1/2 wave dipole and my home made 6 element curtain array - YouTube

...and this is an on the air signal report using the six element curtain array during a contact from my location in South Carolina to a station in New Mexico.

30 over signal report in New Mexico with 200 watts output on my 6 element curtain array! - YouTube

I have been using this antenna for a few months now, and of all the antennas I have ever used for DX since I started playing with CB radios in 1975 this antenna is the best!

Night Ranger/South Carolina 116

W5LZ said:

...but can you turn it?
- 'Doc

Click to expand...

It does a complete rotation every 24 hours. Unfortunately the receiving station turns with it.

: )

m42duster said:

I like it. Can u post a drawing?

Click to expand...

I do not have the full registered version of EZNEC, so I cannot allocate enough segments to accurately predict the gain. My best guess is the antenna gain is somewhere between 7.5 dbd to 8.5+ dbd over a halfwave dipole over perfect ground. If someone here has the full registered version of EZNEC perhaps they will do a more accurate plot.

In any case using the free version of EZNEC it looks like this at 27.205 MHz;

Elevation plot over perfect ground. I live near the ocean and a river.
http://www.shadowstorm.com/images/6ElementCurtainArray.jpg

This is the free space radiation pattern when looking down on the antenna.
http://www.shadowstorm.com/images/6ElementFreeSpacePattern.jpg

Night Ranger

2RT307 said:

Very cool, night.ranger! I am impressed with your antenna, and the dramatic difference it makes in your receive. Haven't talked to Chris in a couple of years.... he always cracks me up when he is in agitate mode, but is really a pretty nice guy. Also nice to see that I'm not the only one that gets AM heterodyne interference!

73,
RT307

Click to expand...

He seems to go in to agitate mode when he is bored. Usually when I talk to him he is pretty friendly.

As far as the six element curtain array, I am really happy with it. I could not have hoped for any better performance from it. I have gotten 20 over S9 reports out of Hawaii with it on more than one occasion. I have considered making a 12 element curtain array. The beam width is so narrow with 12 elements I'll have to make it electrically steerable as it would probably only cover about half the west coast at a time. Time will tell if I actually build it.

Night Ranger