Abstract: An improved hand-held sensor having a recessed LED array for indicating the location of an object behind a wall surface. The array displays in an arrow shaped format the location of the sensor relative to the object. The LED's can be offset both laterally and in depth from the surface of the sensor exterior case and are recessed from the surface. The sensor includes a soft feeling slip-resistant gripping surface for the user. One form of the sensor includes a slide switch actuator, which is retained in one wall of the sensor case to enable actuation of a switch mechanism without physical loading on the switch mechanism.

Abstract: A framing layout tool includes two squares each with two legs or blades 90.degree. apart. The squares are pivotally attached at their vertices by a pivot pin including a knurled locking nut. One of the squares includes a longitudinally aligned electronic plumb and level indicator on one of the legs. The other leg of that square includes indicia on a leg reference edge for indicating rise-over-run integers representative of the angular separation of that other leg and a leg of the other square. Indicia indicating the actual angle between such legs is also contained on an opposite reference edge of that other leg. The layout tool has particular utility for accurately marking the location of a plumb cut, seat cuts and a ridge cut in roof rafters where the blade of the second square is placed on an inclined rafter and oriented with the electronic level in a vertical plumb position. When a visual and auditory indication of exact plumb is obtained the clamping nut is locked.

Abstract: An electronic level includes a visual display (similar to a ruler scale) having a number of parallel line segments. The inclination of the device is shown by illuminating various of the scale line segments on either side of the central line. When the device is at a null (typically level or plumb) only the central scale line is illuminated, indicating the inclination away from the null. Each scale line segment indicates 1/64th of an inch of inclination per foot of horizontal distance which conforms to the normal use of such levels by building tradesmen. A multi-tone audio output corresponds to the visual display line segments, with one tone being provided for each increment of inclination arranged in order of the musical scale. A fixed offset mode is provided showing if the device is at a particular slope such as 1/8" per foot. In addition, a variable user offset mode allows indication of any predetermined inclination within the full 360.degree. range.