This series and parallel sensor circuit was found in Popular Electronics from the 1990s. Any SCR can be used and the supply voltage depends on the load.
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...