Abstract: The operating system control device in a telecommunications switch is capable of operating under the control of software instructions associated with a new switch feature for executing a series of actions used to integrate the new switch feature with the operating system. The operating system control device further provides the capability operating under the control of software instructions for testing the operability of the new switch feature. This minimizes the costs associated with the installation of new features and the amount of skilled craft personnel time required.

Abstract: A paddle and projectile kit and method, comprising in combination: a paddle including a face and handle for holding the paddle; and a projectile having a generally rectangular cross-section including at least one projection extending outwardly therefrom.

Abstract: A connector for establishing connection between a printed wiring board and a ribbon-type cable through terminals on the printed wiring board and a corresponding contacts on the cable. The contacts are positioned to engage the terminals when the printed wiring board, the ribbon cable, and a resilient pad are compressed between a base and a frame. The frame is urged towards the base by clamps each including a handle pivoted about a pivot point on the frame acting to pull links, which are engaged with hooks attached to the base, toward the frame. Alignment pins are provided extending from the base towards the frame to position the pad and the ribbon cable and prevent their lateral motion relative to the base. A pair of alignment tongues extend from the base at an oblique angle and engage alignment bores in ears of the frame to maintain the frame in alignment with the base while providing wiping action for the contacts during engagement. A pair of handle locks retain the handles in an operated position.

Abstract: A line voltage sensor and dial pulse repeater circuit for use in conjunction with a digital PABX telephone system connecting a subscriber station to a switching center providing for detection of off-hook condition of the subscriber's set, detection of irregularly shaped dial pulse and correction of the irregularly shaped dial pulses to allow accurate reconstruction of the dial pulses originally transmitted via the subscriber's set.

Abstract: A thick film resistor which fuses at low continuous current yet withstands high voltage pulses. The resistor design comprises a series of smaller thick film resistors disposed on a ceramic substrate, each having laser trimmed kerfs strategically located to control current flow and prevent voltage arcing across the kerfs.

Abstract: A call for service and continuity sensor circuit for use in conjunction with a trunk circuit of a digital PABX telephone system interfacing with a central office via ground start signalling providing for detection of a call for service signal to the PABX by the central office. This circuit also provides the means to effect an open circuit for both signalling and transmission conditions in order to prevent excess loading of the trunk circuit during these conditions. This circuit provides a precise and stable threshold detection level necessary for accurate sensing of the trunk circuit conditions mentioned above despite parasitic leakage current, induced longitudinal power line voltages, and earth potentials sometimes existing on the line connecting the PABX to the central office.

Abstract: A circuit which connects a ringing voltage generator to a telephone subscriber loop without allowing harmful, electrical transient discharges to develop. Relay contacts are used to switch current limiting resistors into the loop circuit and ringing voltage generator circuit to limit transients during transfer of the ringing voltage generator to or from the subscriber loop circuit. These current limiting resistors are then switched out of the loop when the transients have dissipated.

Abstract: An AC supervisory signal detector circuit for use in conjunction with a trunk circuit of a digital PABX telephone system interfacing with a central office providing for detection of relatively low frequency AC voltages which may be superimposed upon a DC bias voltage of either polarity. The circuit is equally responsive to various frequencies used in supervisory type signaling.

Abstract: A detector circuit for use in conjunction with a trunk circuit of a PABX telephone system interfacing with a central office providing for constant monitoring of normal or reverse battery application by the central office during the high impedance idle state or the low impedance busy state. In addition, the circuit provides for detection of: proper loop closure, electrically shorted tip and ring leads, open circuit condition of tip and ring leads or a grounded ring lead. Furthermore, the circuit indicates when current flow of proper magnitude is sensed during normal or reverse battery conditions.