Abstract: A switchboard control system in which a plurality of switchboards are connected to a time division exchange and controlled by the time division exchange. A speech signal and a control signal (a signal for key information, display information, subscriber number information and other information necessary for the exchange operation by a switchboard operator), which are delivered and received by each switchboard and the time division exchange, are transmitted together by a common transmission line on a time-division-multiplexed basis. On the side of the system toward the switchboards are disposed a position controller, by which the signals are multiplexed and separated and the common transmission line and the switchboards are interconnected. For delivering and receiving the signals, common channel signalling equipment is connected to the time division exchange and remote channel signalling equipment is provided in the position controller.

Abstract: A system for correcting the effect of altitude on an engine with a supercharger. A bypass is provided to bypass an exhaust gas turbine of the supercharger and a waste gate valve is provided in the bypass. An actuator is provided for operating the waste gate valve. The actuator has a supercharging pressure chamber supplied with supercharging air, a standard pressure chamber filled with air at standard pressure, and a diaphragm partitioning both chambers. The diaphragm is operatively connected to the waste gate valve so as to open it when the diaphragm is deflected by an increase of the pressure in the supercharging pressure chamber.