This circuit is from a March 1978 Radio Electronics magazine article that showed how to build it. The circuit is TTL based and is powered. The components used can still be found.
Using CMOS circuits and operational amplifiers of the time, this circuit was found in the...
This circuit was obtained from an English magazine from 1976. The circuit operates two LEDs and...
Although it is a common configuration today, this circuit was taken from an old publication. The...