Ultrasonic Emitters and Transducers:

I bought one of these:


and one of these:


and I am basically getting an analog reading from the receiver and turning the transmitter on and off using a delay.

I have 2 arduinos, the transmitter arduino has one side of the ultrasonic transmitter connected to pin 12 and the other to ground.

The receiver arduino has one side connected to analog pin 1 and the other to ground.

The result I get from the serial bus is a seemingly random oscillation of numbers from 1000 down to about 40. It will start at a bit over 900 and work its way down to about 40 then go back up.

I have a feeling there are several things I am doing wrong so any help is appreciated!


There are two amplifiers missing, PA on transmitter side and LNA on receiver.
You can't interface such peripheral devices directly to arduino

You need to drive the transmitter with a 40kHz signal, it doesn't have a built in oscillator.
Similarly, the receiver has no amplifier, so unless you know how to build these, you're better off buying ready made units, like the ones from Devantech.