This circuit was found in the March 1992 issue of Radio Electronics magazine. The circuit has several adjustments and uses an operational amplifier. Note the supply voltage.
We found this circuit in a 1982 documentation, but the circuit can still be easily assembled, as the...
This circuit uses the SQ3524, a switching integrated circuit. The circuit was found in the April...
This circuit is intended for the use as modulated light signals from digital sources. The circuit...