Dual band superheterodyne radar receiver
Dual equipment to identify telephone calls
Dual fixed/mobile communications system
Dual medium dictation recording and transcription system
Dual mode telephone subscriber loop current detector
Dual port interface for a computer based multifunctional...
Dual rate periodic ranging system to reduce time to...
Dual timing circuit for telephone subscriber's instrument
Dual tone multi frequency personal card
Dual tone multifrequency and dial pulse receiver
Dual tone selector with answerback signalling
Dual voltage, self-monitoring line circuit
Dual-band line interface circuit capable of multi-band...
Dual-tone multi-frequency signal transfer protocol
Duplex communications method and system
Duplex interconnect/dispatch trunked radio system
Duplex interphone
Dynamic bandwidth and symmetry allocation of digital...
Dynamic call characteristic control on a per call basis
Dynamic call response system