Abstract: An injection molding machine includes various devices for reducing injection cycle time. A molded article detection apparatus and method are disclosed. The detection system and method determines if an article, or a portion thereof, remains on a machine core pin after the article ejection cycle has occurred, and, if so, communicates this condition to both the machine controller and the take-out controller. This prevents the machine from starting a new cycle and damaging the injection mold. Also, by communicating the extraction status to both the take-out controller and machine controller, if no articles or portions remain, injection cycle time is reduced. Additionally, a variable vacuum pressure apparatus and method are described. The apparatus and method allows early removal of molded articles from the molds into a take-out plate while the parts are still warm.

Abstract: An eight-phase modem is described in which a 2900 H.sub.z carrier has eight phases each representing one of eight tri-bit symbols 000 through 111. The phase modulated carrier is restricted for transmission to a frequency band of 2900 .+-. 50 H.sub.z, and the modem can carry four time-division-multiplex 75-baud teletype channels at 250 bits per second at the upper end of a telephone voice channel without interfering with normal voice use of the channel. Or, the modem can carry eight channels at 500 bits per second in a frequency band of 2900 .+-. 100 H.sub.z. The modem operates reliably despite a carrier frequency translation or shift of up to .+-. 5 H.sub.z in the communications path. The modem extracts a carrier cycle spike from the received signal during each symbol period, and uses the spike to synchronize a locally-generated reference signal, and compares each spike with the reference signal to derive the corresponding phase-modulated tri-bit symbol information.