I did not build mine. I was studying resonant energy. Had to get lots of high tech tools. I have had mine for many years. Only recently did I try to apply it to myself.

I got mine on ebay. Just search "digital signal generator" look for one that goes from 0hz to at least 500khz. Most will go up to the mhz range. You will find everything there from simple units to diy.

I like this site for em toys and plans
[link to www.amazing1.com]

I am happy to help if there are questions.