Touch Sensor

Forum 2005-2010 (read only) Hardware Troubleshooting
1

I'm using the arduino with ATmega168
I connected a Touch Sensor Motorola MPX200D to it (1ste pin on GND, 2th on 5V, 3th on Input 0.
Now I used

int ledPin = 13;                 // LED connected to digital pin 13
int presSensor = 0;
int val = 0;
int TRESHOLD = 512;

void setup()
{
  pinMode(ledPin, OUTPUT);      // sets the digital pin as output
  beginSerial(9600);
}

void loop()
{

  val = analogRead(presSensor);
  
  if (val >= TRESHOLD) {
    printInteger(val);
    printString(" push ");
    digitalWrite(ledPin, HIGH);  
  } else {
      printInteger(val);
     printString("  ");
    digitalWrite(ledPin, LOW);
    }
      delay(2000);  // we have to make a delay to avoid overloading the serial port
}

Now the values are all the same (242 or 243), when I touch the sensor or when I don't touch it.
Normally the values should change when I touch it, or am I wrong?