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• ELECTRIC FIELD DISTURBANCE MONITOR-1
  This schematic is the power supply and front-end sections of the field monitor that is discussed in more detail at Electric Field Disturbance Monitor. The system can detect human and animal motion by the electric fields they disturb.

• ELECTRIC FIELD DISTURBANCE MONITOR-2
  This schematic is the motion discriminator alarm and battery monitor sections of the field monitor that is discussed in more detail a Electric Field Disturbance Monitor. (link is off-site)

• Simple Security Wire Loop Alarm
   A wire is looped through various objects which are to be monitored.  The loop wire is typically an aircraft cable but could also be any insulated stranded wire.  The loop is attached to a table or desk.  Should the loop be cut, the alarm is sounded.