Digital tachograph system with digital memory system

Digitally-operated displacement detecting system

Direct input photoelectric pulse initiator for meter telemetry a

Directional control lever and horn actuating arrangement

Dispenser cover and indicator

Display device for a copying machine

Display system

Door alarm controlled by operation of door lock

Door alarm system responsive to forced entry

Door alert system and magnetic switch therefor

Door operator with automatic control of auxiliary circuit

Doppler detection device with integrator sampling means to inhib

Doppler detection device with phase shift means to inhibit false

Doppler perimeter intrusion alarm system using a leaky waveguide

Doppler shift actuator and intrusion systems

Double detection circuit for conserving energy in fire detection

Double-detecting loop type alarm system

Drainage flow detector

Driver alert device

Drug management systems