This simple TTL siren was found in a 1980s Electronics Today International. The power supply is 5 V and the integrated circuit can be the 7400.
This simple circuit must be powered by a voltage of 5 V. The integrated circuit is the 7400, but...
This circuit is an alternative version of the previous one also found in the July 1995 Electronics Now...
This two-phase stepper motor circuit was found in an old documentation using an operational amplifier...