This helically loaded magnetic loop was designed by Rich K8NDS. when I first came across the antenna I must admit I was skeptical. I built the 10-20m version and I have to tell you it works very well. You have to get use to rotating and tuning the loop. I found it usually works as well as my 200' dipole at 40'. The loop is a great choice for a limited space application. It was easy to build and all the pvc parts are avaliable from any DIY store. The toughest part is the vacuum cap and the control. Look at my web site and look at my youtube site for some ideas. Rich also has a new control scheme on his web site. Give it a try, you won't be sorry. It is also very quite. I have mine mounted about 12' off the ground, but it could be 4' off the ground.