Activity 8a/b – Thermistors I & II.
ACTIVITY 8 – Thermistor
What You Need
• Alpha Kit: Battery Connector
• Potential Divider with Thermistor and Variable Resistor
• Transistor Switch with LED Indicator What To Do
• Build the circuit shown.
• Adjust the variable resistor until the LED is on, then turn it slowly until the LED just goes off. You might have to try different values of variable resistor
• Gently warm the thermistor with your fingers
• What happens?
• What could this circuit be used for?
• Investigate the effect of swapping the thermistor and the variable resistor around.
• You might like to try different output devices (bulb, motor) but you may need a different transistor. The one mounted on a ‘Transducer Driver’ board usually works.
