This protective circuit for power lines was found in a Radio Electronics from November 1957. The transistor used can be any general-purpose transistor such as the CK722.
This two-digit timer was found in the 1983 Special Projects issue of Radio Electronics magazine. The...
This high sensitivity circuit was found in the July 1992 Radio Electronics magazine. The circuit...
This circuit was found in an American 80's circuit board. The components used are current except the...