Environmental Monitoring with Arduino

Make the Gadget

Although monitoring radiation can be tricky, building this gadget is pretty straightforward. More complexity comes in when programming Arduino and uploading radiation readings to Pachube.

The Infrared Emitter

The infrared emitter is unmistakable—it looks like a funky gray LED. But the collector is essentially indistinguishable from a clear LED unless you look very carefully along the vertical axis. The collector looks dark gray when seen from above, while a clear LED looks light gray when seen from above. For this reason, we suggest you keep the emitter and detector in a special place in your parts box, apart from other components—you can go crazy trying to find the collector in a sea of clear LEDs.

Parts

1. Arduino
2. Ethernet shield
3. Breadboard
4. Geiger counter
5. IR collector (RadioShack catalog #276-0142)
6. 1k resistor (color code brown, black, red)
7. Long solid strand wire, 18–22 gauge
8. 1 package of heat-shrink tubing. We used tubing from RadioShack (catalog #278-1611); you can use others.

Breadboard the Circuit

Check your work on the breadboard view (Figure 9-1).

Step 1 Connect one end of a long red wire to the collector lead (the shorter lead) on the IR detector and the other into a row on the breadboard.

Step 2 Connect one end of a long black wire to the emitter lead (the longer lead) on the IR detector. Plug the other end into a different row on the breadboard.

Step 3 Connect a jumper wire from the emitter on the detector to GND on Arduino.

Step 4 Insert the 1K resistor into ...