This circuit was found in a National Semiconductor Handbook from the 1990s. The integrated circuit used is from the time and the circuit is stereo.
The MC15555 of this circuit is the old version of the common 555. What this circuit does is...
We find this circuit in an American 1980s documentation. The circuit can still be assembled...
This circuit triggers an LM380 oscillator, producing an audio tone with light falling on the LDR....