This oscillator uses a small IF transformer taken from an old transistor radio. FET admits equivalents. The circuit can be used to calibrate radios.
This circuit is from a 1976 publication, but it can be easily implemented with a BC548 transistor. The...
This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply...
This simple low current source for the bench was found in ancient American documentation. The...