This 1 kHz circuit was found in American documentation from the 90s. The original operational amplifier consists of a double 741 at the time. The power supply must be symmetrical.
This low voltage lamp flasher can be powered from 12 V supplies. Frequency is adjusted by P1 and...
The transistors in this circuit, found in an American publication in 1975, can be replaced by...
This circuit, from an old publication, can also use modern transistors. Note that the unit is...