Patent · US Expired

Constant percent break type dial pulse corrector

US4207436A · kind A · utility

1Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1978
Grant dateJun 10, 1980
Priority date
Expiry dateJul 26, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q1/36
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The first monostable multivibrator of a series connected pair of monostable multivibrators is responsive to each break interval of input dial pulses for establishing a fixed time delay after which the second multivibrator initiates a corrected break interval and starts a first timing capacitor thereof charging at a rate set by a fixed time constant. Each input break interval also causes a capacitor of a second timing circuit to start discharging at a rate set by another fixed time constant, the time that the second capacitor starts discharging being a function of the pulse repetition frequency of input dial pulses. When the charge voltages on the two capacitors are the same values, the output of a comparator resets the second multivibrator to terminate an output break interval so as to cause corrected dial pulses in the output thereof to have a constant percent break.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.