I am new to using a valve locator, I made my own test site by running wire on top of the ground and wiring in some valves along the path. When I insert my grounding stake and place the hot wire over the wire to be traced I keep getting a tone over the wire instead of a null. I might be reading the directions wrong, but according to the directions I should get a null. When I get on top of the valve the receiver goes crazy which I think it is supposed to. Can anyone please give me some pointers on this thing. I am a new Irrigator (very new) and could use a little help with this. I have called the company (tempo) and all I get is another name and and number to call and I've yet to find anyone to help me. As far as getting a good ground I have even wet the ground with water to try and make a good ground. Should I get a tone or null over the wire, I am sure it is a operator error. Thanks Scotty.