The frequency of this Pierce oscillator, found in 1969 documentation, depends on the crystal. The current in the drain is about 500 uA. Crystals from other frequencies can be used.
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
The sensors in this circuit, found in a 1999 documentation, are stripped wire tips at different levels...
Found in a Hands On Electronics from the 90s, this circuit can be easily assembled today, as the...