Hey guys!!
I'm building a project that has a sensor which when it activates sends gnd signal.For example if the sensor detects something far it will get out of the singal ~1volt (With the multimeter be on (+) on 12v and the
(-) on the output signal) but when it detects something close it gives around ~12v. I tried using npn transistor like i will saw you in the picture but im not happy with that because it trigers after ~2volts.I want the arduino detects it at lowest possible.
The sensor isnt hand made and for this reason i dont want to make modifications on it.
If its a library or a simple code that arduino can read this type signal it would be helpfull.
Thanks for your time.
If you ran the sensor output though a voltage divider going into analog in on the arduino you could trigger at any point.
3-1 voltage divider would change your max input to 4volts which would be easy monitor all the way to 0 volts.
You mean like that,right?
Hi,
Welcome to the forum.
Can you please post link to spec/data of your sensor please?
Thanks.. Tom... 
TomGeorge:
Hi,
Welcome to the forum.
Can you please post link to spec/data of your sensor please?
Thanks.. Tom...
Hello Tom!!
Thank you for the Welcome!! 
Unfortunately i dont have the datasheet or any schematic apout it. The sensor its 2 mics (Left and Right) which they end up on a small circuit.The circuit converts any noise from the enviroment to a signal.This signal is what i take and for bad luck the signal is gnd.Like i said If you put a multimeter the minus on signal and the +12 on positive you wil get results 0-12volts DC.The higher the noise the biger the singal.The purpose that i want it its to triger arduino so i dont mind the how big it will be the signal.I want it just enough so it can triger it.
jamesss123:
Unfortunately i dont have the datasheet or any schematic apout it. The sensor its 2 mics (Left and Right) which they end up on a small circuit.
How about a couple of clear photos then, that might help.
From description sounds like an ultrasonic tx/rx.
Or at least some device with open collector.....everyone is guessing...??
bluejets:
How about a couple of clear photos then, that might help.
From description sounds like an ultrasonic tx/rx.
Or at least some device with open collector.....everyone is guessing...??
Hello there.
The case of the circuit is fixed.Has no screws and its closed with some type of glue.I dont want to break the case and for this reason im trying to figure out how i will convert the signal.
The only info that i have its that the circuit its connected on a car battery and the output when it detects sound it gives a signal (-).
You could put a resistor and an opto-isolator on the sensor and connect the opto outputs to Arduino.
There would have to be enough V to light the opto led to trigger that.
You could voltage divide the 12V to 5V or less and trigger on a digital pin at about 3V or a bit less on a 5V Arduino. Digital pins make good switches.
GoForSmoke:
You could put a resistor and an opto-isolator on the sensor and connect the opto outputs to Arduino.
There would have to be enough V to light the opto led to trigger that.
You could voltage divide the 12V to 5V or less and trigger on a digital pin at about 3V or a bit less on a 5V Arduino. Digital pins make good switches.
Hello!!
This is a very nice idea!!
I totaly forgot optocouplers. I will test it out when i got the chance and we will see!!
Many thanks Mister and have a good Day/Night!!
-James.
Hi,
Even a picture of the sensor as it is may help, a quick google image search...
Thanks Tom....
The project works perfectly with opto isolator!! Thank you all for your time.
Hi,
Good, can you post a circuit diagram of your final project please, so that this thread may be of use to other with a similar problem?
A picture would also help.
Thanks.. Tom..
There you go.
(Sorry for the pic i'm from mobile).
