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.
Found in a 90s General Electric documentation, this circuit has a drain current of just 1.5 uA....
This circuit divides the voltage of a source by 2, allowing its use as a symmetrical source. In...
This low-pass filter with 741 op and symmetrical source was found in the August 1993 issue of...