This circuit was found in a Popular Electronics of the 1990s. The sensor is a rotating mechanical system with a propeller-driven magnet to count pulses with a reedswitch.
Originally indicated as an alarm alert in a 1990s US publication, this circuit can be used as a...
We found this circuit in a Popular Electronics of the 90s. The circuit uses a touch sensor formed by...
This circuit was found in an old American documentation. The transformer is of the type found in...