Three-phase converter (CB21931E)

This circuit was found in the RCA Power Transistor manual from the 70's. The circuit uses power transistors of the time.

Light Alarm (CB24967E)
Based on the CA3140 IC, this circuit was found in the June 1986 issue of Radio Electronics....
Dryness Alarm (CB11960E)
When sensors X1 and X2 stop driving by the dryness of the monitored location, the oscillator...
Proximity Switch (CB6410E)
This circuit works directly connected to the network and special care must be taken with its...