Look simple but difficult.

Today, I try to test one of the sensor first, cause I need to know how it works. I try so hard but there's no output, means the output is always high. No changes with the output value.

The value didn't change.

Many times I tried but the result still the same. Then I make a solution, which is I need to study the characteristic of the sensor first. Because, the datasheet of the sensor is too simple. Here the datasheet : http://www.farnell.com/datasheets/9749.pdf

And yesterday I have construct the whole circuit. Here the picture :

First attempt.

Second attempt.

And my final conclusion for the construction is, I need to study on the sensor first. Because all the test that I have made didn't get the result that I need.