Abstract: Apparatus for controlling temperature in accordance with a source temperature that includes a clock pulse generating circuit that triggers each of first and second mono-stable multivibrators which provide opposite phase pulse outputs having durations controlled by the R-C time of thermistor sensing components. A retriggerable monostable multivibrator is then controlled in response to pulse duration difference to provide toggle energization of heating and cooling sources.

Abstract: A level control apparatus is disclosed for controlling a liquid level between a maximum and a minimum. An elastic circuit generates a reference pulse which receives the pulse and triggers the generation of first and second reference pulses. The first reference pulse has a width which corresponds to the function of the maximum level of liquid and the second reference pulse has a width which corresponds to the function of the minimum of liquid. A capacitance probe supplies an output to a level sensing means which generates an output control pulse which varies in time with respect to the liquid level.