The transistors of this circuit found in a 1965 magazine can be the BC558 and the sensitive 12 V x 50 mA relay. The other components are common.
With the coded activation of the relays, it is possible to control which of the 16 outputs...
The integrated circuit used in this application is not very common. Transistors and resistors...
This simple circuit makes use of neon lamps to indicate the voltage of a power grid. The lamps are...