geotech1.com click on LRL's, click on Reports, Dell Winders VR-800 has a schematic.Be careful as this has enough power to kill you. To increase your sensitivity, rub the palms of your hands together for 60 seconds. Then start about a foot (20cm) apart and move them towards each other and try to feel something there in between your palms. Maybe pressure or a tingle feeling. If you are good you can feel the signal line by just holding your hand over it. I like to stand in line with the signal line and hold my arms out. Sometimes i do better than with the rods.Another one is to turn the water faucet on and surround the flow with your palms, do not touch the water. Maybe a minute or two. Another only works for a short time, get your hands wet or have a jar of saltwater and pumice. Use a cloth to rub into the palms of your hands.
All this is worthless if you can't keep your mind out of the way. And I don’t mean to harp on this, but negativity is the real killer. It is essential to overcome any negativity. I know how difficult it is because there are times when the locator will not work, NO equipment will work. Use a visible test target to see if you get a signal line. Even this is difficult to do without wishful thinking (You must quiet the mind). I can testify it is hard to learn on your own, but it can be done. For me, the hardest thing was to use a visible target. I always wanted to "get a response" and many times I would force the rods to close, no matter what. Well, that's enough to get you started. Too much info is hard to digest,like learning a golf swing--so many things to consider.
BTW, you will be tested to see if you succumb to the gross negativity in the VR-800 article. LOL Or you can buy a cheap DDS frequency generator and attach an amplifier. This link gives you a bit of the principles how LRL's seem to be able to do the impossible.
http://amasci.com/tesla/tmistk.html#google_vignette Hope this helps.