This high-Q low-pass filter was found in the October 1990 issue of Radio Electronics magazine. The frequency depends on the capacitors used and is on the order of a few tens of hertz.
An interesting type of sensor for specific applications is the sensor formed by piezoelectric...
This circuit is from Radio Electronics from the 90s. It supplies a voltage between 800 V and 2 000...
This circuit was obtained in a 1989 publication and is quite simple to assemble, but critical in...