We found this circuit in an English publication from the 1980s. The circuit uses current components and can be tuned for frequencies between 300 and 1500 Hz.
This field effect transistor amplifier circuit in common gate or common port configuration is from an old...
This circuit was obtained in an old American documentation. The integrated circuit used is...
This zero crossing detector is of the 1993 Motorola Linear Interface ICs. The source is...