This circuit, suggested by an Electronics World of 1969, keeps a blinking LED for a while when a power outage occurs. Time depends on capacitor C1.
This Hughes circuit is from 1968. Equivalent modern components can be used. The input impedance is...
This circuit uses a 7-segment display to indicate the logic level of a test circuit. The power...
The gain for this circuit is given by the ratio R1/R2. The circuit must be powered from a dual...