Roman numeral display (CB22160E)

This circuit shows numbers I II and III when mounted on its side, depending on the position of the selector switch.

Proximity Relay (CB13987E)
The circuit presented is from a 1977 Italian magazine (Elettronica Pratica). We can mount it with...
Divider by 5 4 or 3 (CB6899E)
We found this circuit in documentation from Ferranti from 1968. The circuit uses transistors from that...
Lights on warning (CB6044E)
This circuit makes use of an old Texas Instruments component. The buzzer is also from the era. The...