This well-designed bistable circuit was found in a 1970s documentation. Transistors can be current types and germanium diodes. The voltage depends on the logic used and can be made with 5 V.
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This circuit was found in a 1974 publication. It provides a tone indication of the temperature sensed by...
This is a simple rheostat circuit for motor control that works with voltages from 6 to 12 V. The...
This circuit with TTL compatible output was found in a 1968 US documentation. The circuit is...