I have been planning to use a room thermostat to control the bulbs inside my incubator, but I don't think they are suitable anymore.
Most of them only go up to 30-35 degrees C, and I need 37.5 degrees C, also the hysteresis (range that the temperature fluctuates) isn't always very good on room thermostats, and eggs need to be kept at a tight temperature.
So now I am either thinking of buying a reptile thermostat off eBay, looking at around £20-30. I know they are good as I have one for Hughie (pictured right), his is a HabiStat Dimming Thermostat.
They only go up to 34 degrees celsius, but to get around this you can put the sensor probe in a cooler part of the incubator, but as there is a fan, there shouldn't really be a cooler part of the incubator.
There is always one of the PCB thermostats (left) which I could use. I won't go for the unassembled ones, as I'm not good at soldering, but you can buy assembled ones. I should be able to wire the thermostat to a heat source and power supply. They run off 12 volts.
I also need to buy a hygrometer, they measure humidity. You can get digital ones (left) or analogue ones. The digital ones are more expensive but I prefer them because they seem more accurate and they also normally have a temperature reading on them too. They need to have a sensor probe on them, and that has to measure humidity, not just the temperature.