This circuit was found in the February 1971 issue of Radio Electronics magazine. It is designed to power the previous circuit, providing a maximum current of around 50 mA.
When a small air current reaches the piezoelectric sensor, a small audio signal is generated and...
This circuit, from the 1977 GE semiconductor manual, uses a unijunction transistor beyond the...
The logarithmic response of this amplifier with operational is given by the presence of the...