Thanks for the interest to look at the thermocouple outputs, something I would like to see myself. Most of what I have figured out is from rummaging around on the net. I still have things to check out and compare (I'll use the AD595 for that as it's accurate to 1*C).
Time will tell whether I can find the specification for that sensor
If the sensors are truly 'K' type their output should be a given. Roughly for a 'K" type is 41uV/C or 0.000041V/C. So your probe could simply be C=A*24390 (This should work, I'm not sure if this was what I had before).
This figure is the difference between the heated joint of the two wire's and the cold end (cold junction). So not the true temp.
So to get that you have three options.
I) Stick the cold end in a ice bath. There fore the cold end is 0*C and the voltage output would be equivalent to a conversion true temp.
II) Build another circuit with a thermistor to measure ambient temp and add that to the calculated out put from the thermocouple. This is what is normally done on equipment using thermocouple's to measure temp.
III) Or the third option (which is what I did). Add the ambient to the above formula. This has to be done each time it is used. So the formulae will be (off the top of my head ) C=(A*24390)+ambient.
This method is not entirely accurate probably more indicative. Although the K type is almost linear, it is not quite. As I mentioned it is hard to check the accuracy. Here's a link on thermocouples
And a vid.
And here's another good one that points out points of error that may need addressed.
This does bring up the point of cable extension (setting up other unwanted extra TC junctions). Which should be taken into consideration. But at that same time there is some contradictory arguments about that (which seem to have some logic to it). Anyhoo's it something that has to be remembered.
All these things need to considered because of the small inputs that are being worked.
Note: If you buy a cheap thermocouple from the electronics store you can chop it up into many thermocouples.