Indicated on an 80's Radio Electronics, this circuit provides at its output a voltage that is the peak value of the input voltage. The supply voltage must be higher than the expected peak.
The diagram shows a simple way to adjust a 7805 to have output voltages up to 12 V. The circuit is from...
This circuit turns on and off when a short pulse is applied by SW to the input of the first...
This circuit is from a 1965 General Electric Hobby manual. The circuit uses only passive...