A REMOTE CONTROL CIRCUIT, ESPECIALLY AN INFRARED RADIO REMOTE CIRCUIT, INTENDED TO GOVERN ONE OR MULTIPLE FUNCTIONS OF A DEVICE

摘要

A remote control circuit for the control of one or more functions of a device, for example a toy or transparency projector, comprises a transmitter for transmitting control signal pulses and a receiver for evaluating the transmitted pulses, the design of the transmitter being such that the number of its components and its consumption of current are minimized. The transmitter accordingly comprises a monostable multivibrator with two complementary transistors. The collector of the first transistor is connected to the base of the second transistor, and the collector of the second transistor is connected to a signal pulse transmitting component, for example an infrared diode, and through a resistance-capacitance coupling to the base of the first transistor. Also connected to the base of the first transistor is a number of components determining different pulse intervals and corresponding in number to the functions to be controlled. The components can be individually switched in by respective switches. The receiver comprises a resistor-capacitor charging-circuit adapted to provide a sawtooth voltage dependent on the pulse intervals and a voltage level detecting stage for detecting different voltage levels and selectively controlling the functions in dependence on detected levels.