I´m playing around with some PIR-Sensors (I don´t know the exact type) and I don´t have any experience in designing circuits for this type of sensor. I have googled some basic circuits and I took a look into the D203B datasheet to get some ideas how I have to design a circuit for this sensor. I want to test this one:
But the transistor doesn´t pull down the signal line. I have measured the output voltage of the sensor and my oscilloscope displays a voltage of 520 mV, but this voltage doesn´t change when I move my finger in front of the sensor. So I´m pretty unsure if this sensor is broken or if my circuit is "too cheap".