Schematic Rise

Most of people have there own vehicles.so I suppose this circuit will be very useful circuit for them.This circuit is a car reverse horn.If you can build your own circuit for your car I think that is great.Here I have used common Music generator IC UM 66.The out put voltage of UM66 is not enough to make a good car reverse horn so by using two transistors (BC148 and BEL187)I have increased it.

This is a simple Car Alarm Arming Horn Beep Canceller schema Diagram. Its a great convenience that most modern cars come with a built in alarm, however it is nothing but noise pollution that the horn sounds when the alarm is armed. Disconnecting the alarm system from the horn relay will eliminate this, but prevent the horn from sounding in the even of an actual alarm. This schema serves to silence the arming beep yet maintain the alarm by introducing a small delay into the signal. It sits between the alarm and horn relay. The alarm must provide a constant horn signal for at least 3 seconds before the horn relay is activated. That way the quick "beep" will never activate the horn relay, while the constant alarm signal will.

Car Alarm Arming Horn Beep Canceller Circuit Diagram