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.
This circuit turns a lamp on and off with alternate touches of a switch. Modern Darlingtons can be used....
This circuit with the CK722 was found in a Raytheon publication from the 60's. The relay is of the...
This circuit was found in Radio Electronics magazine from July 1960. The components used are...