This an old commercial receiver found in a year 1958 magazine. The circuit uses some transformer available that timer and the transistors are germanium types. The circuit is intended to receive MW stations.
Found in American documentation from the 90s, this circuit has the signal frequency determined by...
This simple circuit detects when a conductive liquid reaches the sensors. The circuit has no...
This circuit appears elsewhere in this section. This version is from General Electric from the...