This sensitive 5-band circuit was found in a September 1995 issue of Electronics Now magazine. The headphones, for greater sensitivity, should be high impedance.
This car alarm was obtained in a Signetics documentation from the 1980s. The circuit uses the 555...
This circuit was found in an English magazine from 1979. The magazine no longer exists, but the...
This integrated is indicated for sound systems of stereo televisions and stereo radios. Its pinout...