Data communications network testing system

Data indicator unit

Data input control system

Data modems having data drop-out and data echo protection

Data output format modifying system

Data scrambler

Data security module

Data set with bridge for duplex operation

Data telecommunication system

Data terminal for connection to telephone or teleprinter facilit

Data transmission and display system

Data transmission system for transmitting primary and secondary

Database encryption and decryption circuit and method using subk

Decoding equipment especially for a typewriter intended for hand

Decoding process and apparatus

Demountable bearing and shaft assembly

Derangement detector in a receiver of a system for data transmis

Descrambler subscriber key production system utilizing key seeds

Device and method for digital video transcoding

Device for aiding abdominal muscle control