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 the 80's integrated circuit manual itself. The component is not as common today...
This circuit has been found in an old documentation and therefore uses a lamp as an indicator. In a...
This circuit generates a tone of a bell and can be used in this type of application. The circuit is...