We found this circuit in an article that describes several alarms that are in the sequence in our section. The article is from the Radio Electronics magazine of May 1971.
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...