This sensitive three-transistor circuit was found in Electronics Now magazine and is earphone-readable. The tuned range depends on the coil.
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...