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.
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Note
# This circuit operates with 12V power supply
# Build this circuit on a PCB to get good results
# use 8ohm speaker.
# Use only push to on switch.
Source by
Free circuits4u