Siren in a box (CB7093E)

Found in Elementary Electronics from 1970, this circuit is a toy for generating different types of sound effects. The circuit is battery powered.

| Clique na imagem para ampliar |

Matrix Switching (CB15407E)
This circuit shows how it is possible to control 9 loads with only 6 Triacs using the matrix...
Stereo Balance Indicator (CB6001E)
This passive circuit was found in a 1980s documentation. The circuit serves to indicate the...
Self-powered monitor (CB8983E)
Placed in the vicinity of a telegraphic transmitter (CW), this circuit produces an audible signal on...