This circuit is from the Texas Instruments operating amplifier manual. Any operational can be used and the font need not be symmetrical. Rf and Rg determine the gain of the circuit.
When the input of this circuit goes to high level, the LEDs start to flash alternately. The...
This circuit already uses an integrated circuit from the time. Note the different encapsulation of the...
This power charger was found in a 1990s issue of Popular Electronics. Integrated circuits must be...