I have a Stalker set up to log the LED pulse from an electricity meter. The sensor is an LLS05-A http://www.futurlec.com/Light_Sensor.shtml connected via digital pin 3, 5V & GND with a 10K resistor between Vout and GND.
It all works very well running off a 9V PP3 battery connected directly to Stalker. I would like to use the Seeedstudio Solar shield to provide the power via a LiPo battery but there are problems. When powered from the Solar shield (battery or USB) the sensor is flickering on and off very quickly causing an incorrect data count. The project has an LED on analog pin 0 which cycles between on & off each time a pulse is detected from the meter LED via the sensor. This LED allows me to ‘see’ the sensor tripping incorrectly and the data logged shows very high values to confirm this.
The sensor is work via an interupt: attachInterrupt(1, wattSensorInterrupt, RISING);
Any idea what would be causing this & how I could fix it?