I bought this couple of ultrasonic sensors, apparently one it's emitter and the other is receiver. The only different between them is a red dot. Can't find any datasheet telling how to connect to arduino. Anyone used this? How do I hook it up?http://i.imgur.com/dZY5uVh.jpg
http://i.imgur.com/K5IAhmT.jpg
Thanks
I'm sorry to disappoint you, but it is not going to work.
Mostly a 'R' and 'T' are written at the back for the Receiver and the Transmitter.
http://www.engineersgarage.com/insight/how-ultrasonic-sensors-work?page=2
But those ultrasonic sensors can not be used with an Arduino.
They need extra hardware that detects the timing. That why they come as modules, which can be used with the Arduino.
http://code.google.com/p/arduino-new-ping/
The ultrasonic sensors like the HC-SR04 use a little PIC processor to generate two 40 kHz square wave signals that are 180 degrees out of phase. These go to a MAX232 chip to boost the voltage from TTL (0V/5V) to RS232 (+12V/-12V). This puts a 24V signal across the sender. The PIC enables the output for a brief time and looks for the highly amplified receive signal. You will need the voltage shifters, amplifiers, and other electronics to use the raw ultrasonic transducers.
I would guess that the one with the red dot is the receiver, if that helps any.
I would give up on the raw transducers and get the HC-SR04 for $1.96 with free worldwide shipping:
http://www.fasttech.com/products/0/10000007/1012007-arduino-compatible-hc-sr04-ultrasonic-sonar
johnwasser:
The ultrasonic sensors like the HC-SR04 use a little PIC processor to generate two 40 kHz square wave signals that are 180 degrees out of phase. These go to a MAX232 chip to boost the voltage from TTL (0V/5V) to RS232 (+12V/-12V). This puts a 24V signal across the sender. The PIC enables the output for a brief time and looks for the highly amplified receive signal. You will need the voltage shifters, amplifiers, and other electronics to use the raw ultrasonic transducers.
Basically this - that said...
johnwasser:
I would give up on the raw transducers and get the HC-SR04 for $1.96 with free worldwide shipping:
Give up? Where's the spirit of hacking and learning? Now, certainly the OP isn't going to spend less than $1.96 to build such a sensor, but they might gain much more understanding.
Now - I say this with the following caveats - if you don't own an oscilloscope, and you don't know what the resonant frequency is for the transducers - building your own ultrasonic sensor is going to be difficult to impossible. But - if you have such a tool and the information on the parts - then you can start to play.
John's description above is basically the idea; but nothing says you have to use a PIC - you could use the Arduino instead to generate the signals needed. Here's some examples:
https://sites.google.com/site/wayneholder/ultrasonic-rangefinder
http://www.kerrywong.com/2011/01/22/a-sensitive-diy-ultrasonic-range-sensor/
Now - all you'll likely need to build the device is to know the resonant frequency of the parts, and access to an oscilloscope (and it doesn't have to be anything fancy - 1 MHz of bandwidth should be plenty).
