discriminating ringing
1discriminating ringing — See distinctive ringing …
2Number Five Crossbar Switching System — The Number Five Crossbar Switching System or 5XB switch, designed by Bell Labs and made by Western Electric, was in use in Bell System telephone exchanges from 1948 to the 1980s. Its principal use was as a Class 5 telephone switch, though… …
3Panic Disorder — Panic has always been considered a symptom of larger psychiatric illnesses. Yet, only recently has it come to be considered a disorder of its own. The whole panic story is interesting as an example of how symptoms wax and wane in the history… …
