Coin-telephone auditor

Abstract

An auditor system (10) includes a control circuit (30) that employs an off-hook detector (32) connected across the tip and ring lines (12 and 14) of a coin telephone to determine whether the coin telephone is off hook. It also employs a step-pulse detector (36) connected across the step relay terminals of the coin telephone, accept-pulse and reject-pulse detectors (40 and 42) connected across its accept/reject relay terminals, and a coin contact sensor (48) connected across its coin-contact terminals to keep track of the number of coins of each denomination accepted by the coin telephone. When the auditor system determines that the coin receptacle has collected a predetermined volume of coins, it connects a high-current power supply (18) across the tip and ring lines and thereby powers a transmitter (68) that sends dialing signals over the telephone lines to call up a data-collection computer at a remote location. Upon detecting, by means of a tone receiver (72), that the call has been answered, it employs the transmitter to send a request that the money in the coin telephone be collected. It also sends other information at the same time and receives information from the central computer for resetting some of its registers. Through the use of this type of auditor system, there is no need for the central computer to poll auditors at a number of coin-telephone locations, separate data lines are not needed, and the amount of communication over existing lines is kept to a minimum so that telephone traffic is not unduly increased.