This circuit was suggested by a 1967 General Electric manual. The waveforms of the generated signals are shown next to the diagram. Equivalent modern SCRs can be used.
This window comparator circuit was found in a Popular Electronics from the 90s. The circuit has a...
Found in Radio Electronics from the 90s, this siren finds many variations on this site. The...
This circuit with automatic gain control was found in the July 1988 issue of Radio Electronics magazine....