Abstract: A personal security system monitors the location of objects, such as a billfold, purse, pen, camera, jewelry, and other personal items, relative to a transceiver, or base station, which may be housed in a cell phone, PDA or other item having a power supply. The base station generates an rf signal throughout a predetermined radius of operation. The items to be monitored all carry unique rf identification tags, which can be passive, active, or semi-passive, which are transponders that receive and acknowledge receipt of a signal to the base unit. The base station is passive while the monitored items are in the protected zone, but when an item is removed from, or moves out of, the protected zone, the acknowledgement signal is no longer received by the base unit. It will then provide an audible alarm, or other sensory signal to alert the user the object is no longer within the protected zone.

Abstract: A safety electrical plug has two-part prongs. Each prong has a distal portion that is electrically insulated and a proximal portion that is conductive. Substantially full insertion of the plug into a receptacle is required to establish an electrical connection between the prongs and the receptacle contacts. This limits the chance of electric shocking by human or animal engagement of the exposed portions of the prongs subsequent to only partial insertion of the plug into the receptacle, and signals the partially-inserted condition when subsequent attempts to operate an electrical appliance connected to the plug fails. The conductive prong portions may be inserts in a nonconductive base, or be the entire proximal portions, which may optionally mount a strip of non-conductive material along their edges.

Abstract: A safety electrical plug has two-part prongs. Each prong has a distal portion that is electrically insulated and a proximal portion that is conductive. Substantially full insertion of the plug into a receptacle is required to establish an electrical connection between the prongs and the receptacle contacts. This limits the chance of electric shocking by human or animal engagement of the exposed portions of the prongs subsequent to only partial insertion of the plug into the receptacle, and signals the partially-inserted condition when subsequent attempts to operate an electrical appliance connected to the plug fails. The conductive prong portions may be inserts in a nonconductive base, or be the entire proximal portions, which may optionally mount a strip of non-conductive material along their edges.