We found this circuit in the April 1979 Radio Electronics magazine. Note the filter capacitor bank that can now be replaced by a single equivalent value capacitor.
This battery-powered micropower supply was shown in Radio Electronics magazine in 1991. The...
Found in a 1965 Electronic Design, this circuit can be made with modern equivalent transistors. The...
In this circuit, the current in solenoid X1 can be adjusted and its intensity measured to the...