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.
For a negative voltage of -48 V, this circuit from the 2005 Linear Technology manual makes use of an...
Found in a 1980s telecommunications documentation, this balanced modulator circuit uses...
This circuit is from a 2005 Linear Technology publication. It converts current into load sensing...