I would like to build my own egg incubator using mterials from old electronic gudgets. Temperature control is one thing that i want to be done automatically. I want the temperature to be maintained aroung 39 degrees celcius (99 degrees fahrenhieght). Any circuit dirgram and sugestion of which old electronic gudgets do I get the parts.

 

You can get ready made pcbs using led displays with an accuracy of +/-1C they use a thermistor sensor with relay output..

https://www.ebay.co.uk/itm/Digital-...sh=item5b7b8809e9:g:yBMAAOSw4ZNfPdWI&LH_BIN=1

The question is what voltage/current will you be using for the heater ?

 

Simplest circuit can be made from heating element (incandescent lamp) and from bimetallic contact connected in series.

 

hi W,
I guess you know that the eggs will need a turning mechanism.
E

 

And humidification.