Searching a construction site where they tore down houses, half a block in size. Two house sites are trashy but I've found stuff. On one side near a side road, there are lots of orange broken bricks under the ground and the backhoe mostly uncovered them. It looks like it was an old brick walkway. Also black dirt like coal or something was burned there. It seems like this is an old area and should be producing some finds. But when it seems like a good signal and dig, there's nothing there. Sensitivity is about 20. I've tried ground balancing. Detector is minelab 705. Have been using 3 kHz 9 inch and coiltek 3khz. I might try the 6 inch HH and see if that does anything.