Pressure switches are used in this circuit that quickly turns off the supply of a load if necessary. The circuit is from a 90s Popular Electronics.
This power source was found in documentation from the 1970s. The components are from the time, and...
This 80's circuit has an input resistance of the order of 880 M and gain 10, using operational...
This 9 V battery eliminator was found in Radio Electronics magazine from June 1966. The transistor is of...