We found this circuit in a 1986 documentation. It uses only LEDs, batteries, resistors and the power supply which can consist of 4 batteries or a 9V battery. The basic circuit uses two-color LEDs.
The crystal in this circuit is 32.758 kHz used in TV. The circuit was obtained in an English...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This very low current circuit was found in the April 1995 issue of Electronics Now magazine. The...