This filter, which rejects frequencies around 1 kHz, was found in the August 1993 Electronics Now magazine. The fine tuning is done at R3, and the source must be symmetrical.
This is a basic astable circuit using the 555 IC and driving two LEDs. The phase on a rate giving...
This circuit triggers a relay when it gets dark, thus enabling the lighting of fluorescent lamps, which...
When the illumination decreases, this multivibrator starts up, causing the lamp to blink at a...