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.
We found this circuit recent English documentation. The circuit uses a common transformer and can...
Found in a 1969 neon lamp publication, this circuit provides two voltages under very-low currents....
The MC1556 integrated circuit is an operational amplifier from Motorola. The circuit is from a...