Based on a 555, this 80's American documentation circuit detects the voltage of a battery and can then disconnect the charger. The transistor may be a general purpose type.
This circuit causes an LED to flash at a frequency determined by the capacitor. The circuit has an...
This low power two-phase motor control was obtained in a 1989 publication. The circuit is for...
This circuit was found in European documentation from the 1980s. The unijunction may be 2N2646 and the...