This lead-acid battery charger was found in a Popular Electronics from the 90s. The circuit has a maximum current of 2 A, being suitable for powering inverters in emergency lighting systems.
This circuit is from an August 1984 Radio Electronics magazine. It monitors the state of a RAM...
In the figure we have the way to obtain an adjustable constant current source of 2 mA. The...
Found in a Maxim publication from the 90s, this circuit generates signals from 10 to 25 kHz with a...