AC Tachometer (CB9353E)

This circuit was found in a 1969 EEE. It detects when there is a phase failure in a circuit using an inductive sensor.

| Clique na imagem para ampliar |

Variable Voltage Controlled Attenuator (CB4236E)
This circuit was obtained from an American 80's documentation. The balanced mixer can be shown in...
Harmonic generator (CB9454E)
Found in a 90s Electronic Design, this circuit generates harmonics from a sinusoidal input signal....
Water alarm with lock (CB6957E)
Published in an old Popular Electronics, this circuit makes use of components that are still...