Sawtooth generator 555 (CB21229E)

This circuit was found in a Popular Electronics from the 90s. The frequency is given by R2 and C1.

| Clique na imagem para ampliar |

Single Pulse Generator 555 (CB13280E)
The MC15555 of this circuit is the old version of the common 555. What this circuit does is...
Sophisticated Alarm (CB4865E)
We find this circuit in an American 1980s documentation. The circuit can still be assembled...
Light alarm (CB22056E)
This circuit triggers an LM380 oscillator, producing an audio tone with light falling on the LDR....