Patent · US Expired

Coin telephone station simulator and condition indicator

US4022987A · kind A · utility

6Cited by
3References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 30, 1976
Grant dateMay 10, 1977
Priority date
Expiry dateMar 30, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/248
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A coin telephone station simulator and condition indicator. Separate tip, ring, and ground input/output conditioners are provided for connection to a telephone system for test. A controllable coin present relay simulator circuit is switchable from a first high impedance condition to a second lower impedance condition in between tip and ground conductors. A coin test switch switches the controllable relay simulator circuit from the first to the second condition. A coin present indicator is provided together with means for energizing the coin present indicator when the simulator circuit is in the second lower impedance condition. Coin collect and coin return indicators are provided. A coin collect and return detection circuit is responsive to first and second electrical signals, of opposite polarity, momentarily and separately applied in between the tip and ground conductors for individually energizing, respectively, the coin collect and coin return indicators. Low, acceptable and high voltage indicators are provided. A line voltage detector circuit is responsive to an electrical signal applied between the tip and ring conductors of below a first voltage level for enabling the low in…

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