Abstract: Briefly, this invention contemplates the provision of a call pacing method in which the number of calls to dial is periodically (e.g. every two seconds) determined on the basis of anticipated operator availability. The determined number of calls are dialed, subject to a limiting function. Calls in progress are interrupted in a short time slot just prior to first ring if the number of operators available to respond to an answered call falls below a predetermined percentage of the total number of system operators.

Abstract: This telephone solicitation system provides automatic dialing and call-progress detection. Audio signals on the line are analyzed to recognize network operation tones, noise bursts, and speech. A "sample" is the total number of crossings during a 25 millisecond period. A "window" is a sequence of eight samples analyzed for spectral and time patterns.

Abstract: A solid-state telephone trunk interface circuit provides high isolation between a central office and telephone equipment. Opto-isolator transistors and a transformer are used to isolate the central office and the local equipment portions of the circuit. A switching transistor (Q4) is connected between a ring connector (3) and turned on and off via an opto-isolator transistor connected to a control connector (9). A ring detector (11) comprising a first diode bridge is connected between tip and ring connectors (2 and 3) via an opto-isolator transistor to a ring signal connector (13). First and second parallel and opposite sign line condition detectors are respectively connected between tip and ring connectors and via opto-isolator transistors to battery-reverse and battery-forward signal connectors (19 and 17). The voice circuit includes a second diode bridge connecting tip and ring connectors to a first winding of a transformer (T1).

Abstract: A method for controlling arrivals to servers, comprising: regulating arrivals, by initiating a processor generating arrivals or by re-routing or turning away arrivals; measuring durations of service; computing and updating time statistics, including mean, minimum, maximum expected and standard deviation of duration of service thereby estimating expected duration of service; measuring transit times from the point of regulating arrivals to start of service and thereby estimating expected transit times; measuring a ratio of numbers of service initiations to numbers of arrivals at the point of regulating arrivals; recording starting time of each current service; noting present time; comparing present time to starting time, and thereby determining time in progress for each service; comparing time in progress to expected duration of service, and estimating time remaining in service for each customer currently in service; comparing estimated time remaining in service to estimated transit time from the point of regul