This circuit uses an unusual operational amplifier nowadays and has a very low consumption. The number in parentheses corresponds to the second channel, for a stereo version.
This circuit uses LDRs as sensors and can either detect the incidence of light on the sensor or...
This circuit was found in a PE Hobbyst Handbook. It makes use of a piezoelectric transducer of the time....
This circuit can be used as a clok in digital applications. Power supply is 5-V and the pins for...