This circuit was found in the October 1983 Radio Electronics issue. It is applicable to old analog telephones. The circuit uses common components.
This battery circuit provides a charging current of 500 mA depending on the solar panel. The...
This circuit was found in an Analog Devices manual and can supply a 3 mA current or drain a 10 mA...
This circuit has its application suggested in an alarm system. The circuit is from an old RCA...