Found in a Popular Electronics from the 90s, this circuit uses components that are still current. The circuit triggers the vehicle's horn. The sensors can be increased in number.
This is the same amplifier circuit as the previous circuit adapted to operate with a single...
To a 16-0hm load, this amplifier provides a power of 10 W. We found this circuit in a Motorola...
This circuit was found in a 1970s American documentation. It can be applied to almost any...