I bought one of these:http://www.maplin.co.uk/ultrasonic-transmitter-40khz-16mm-open-591658
and one of these:http://www.maplin.co.uk/ultrasonic-receiver-40khz-16mm-open-591659
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!