This circuit is from a 90's documentation. The circuit is simple, as it uses only two transistors, and the control is done by pressure switches. The indication is done by LEDs.
This low frequency circuit was found in documentation from the 1980s. The values of R and C...
This source for devices for automotive use was found in a 1985 documentation. The power...
Found on Popular Electronics in the 1980s, this circuit detects a change in air pressure using a...