Making XO sensors/Making a Thermistor

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You need:

  • a thermistor,
    • The thermistor should have a resistance about midrange in the XO's measurement range at normal temperatures, for example the TDC05C247 which has a resistance of 4700 ohms at 25C will give a good range of measurement

Thermistor 01.jpg


As shown in the picture, tear the two ends of the wire apart and use a Stripper to strip the wire bare.
Slide on the X (heat-compressible rubber tubing) onto both ends of the wire as shown. Only one side is shown in the picture, but follow the same process for the other wire.

Thermistor 02.jpg

Next, use the soldering iron to connect the two ends of the wire to the sensor. This can be done by adding some solder to the two wires emerging from the thermistor and to the bare ends of the wire. Subsequently, join the two together as shown in the picture, and allow the solder to cool, solidify and thus connect.


Next, slide the rubber tubing up the wire so that it completely covers the two contact points, and then use X (hot air) to compress the rubber tubing onto the wire.

Thermistor 03.jpg

Quick refresher of the different steps!

Thermistor 04.jpg

A finished sensor that can record changes in temperature!

For how to calibrate your sensor see http://wiki.sugarlabs.org/go/Activities/TurtleArt/Using_Turtle_Art_Sensors#Measuring_Temperature

Other sensor instructions