This circuit was obtained in a Hands-On Electronics from the 90's. The circuit turns on one LED at the end of the timer, erasing the other. The timing can be increased by changing C1.
Found in the September 1972 issue of Radio Electronics magazine, this signal injector is based on the...
This is a traditional configuration of a series regulator with zeners, found in a documentation from the...
This small pulse receiver had its construction described in a Radio Electronics magazine from...