This two-tone decoder has a bandwidth of 24%. The circuit is from a 1994 Electronics Now. The components without the value determine the recognized frequency.
This circuit for igniting gas flames was found in a 1967 Electronic Design. The SCR firing device is a...
This RF wattmeter was found in an American 1980s documentation. The components are common and the...
This signal follower, from a publication from the 1970s, uses old germanium transistors such as...