This circuit with the PLL4046 was found in the October 1994 Electronics Now magazine. The transistor is low power, and the volume obtained is small.
An interesting type of sensor for specific applications is the sensor formed by piezoelectric...
This configuration with the 741 Operational Amplifier has an NAB equalization for magnetic...
A version of a monostable that uses the 4528, but is triggered by negative transitions of the...