This circuit was found in a 1999 publication. Its purpose is to flash two LEDs according to the sound of an equipment and to randomly flash three LEDs at a controlled frequency
This circuit was found in a Popular Electronics from the 90s. The circuit uses TTL technology and...
This circuit was obtained in the manual of the used integrated circuit. Equivalents may be used...
This circuit simulates a UJT, with two bipolar transistor. Frequency is given by C1 and P1...