This circuit supplies 5 V from two AA batteries. The output current is 4 mA, resulting in an 11 mA input current from the batteries. The circuit is from an old EDN.
This simple expandable circuit was obtained from a Popular Electronics from the 80's. The supply...
The frequency of the LC resonant circuit must be the same as that of the crystal and the JFET...
This circuit was obtained in a Popular Electronics of 1991. The magazine no longer exists, but the...