Try researching RTDs, thermocouples, thermistors, bimetallic thermometers, and IC temperature sensors. All are available with wide differences in characteristics from a variety of suppliers. Some of the above are active or passive electric/electronic devices, others require no electrical input. You could check with electrical supply stores, electronics stores, scientific equipment suppliers, etc. I don't want to specify any source by name, as I don't feel these forums should be used to promote any specific company over any other. Besides, from what I listed above, you should have no problem finding sources on the Internet. E-mail me if you need more information on the advantages and disadvantages of the types of sensors I listed above. Best of luck.
Temperature indication is a very advanced project. There are two good ways I can think of now. Easy Way : You could easily rig up a thermocouple(LM25Z) to a small millivolt meter and make checkpoints of different temperatures. You would calibrate this with a mercury thermometer. Or you could go the hardway
You could make a digital thermometer. (just buy one really, lol) It is very difficult to design and I havent to see a schematic yet. If your VERY interested in doing this yourself. I could design a thermometer for you(i am facing this challenge too, with a remote temperature sensor) and send it whenever I am finished.
Contact me, any questions
Steve McFadyen.
scubasteve_911@hotmail.com [sig][/sig]
use Lm 335 national temp sensor provides 10 mv/ deg k , use front end diff amp to scale to degc / degf then connect it to a dpm to read temp of your interest , i think usual full scale range for this device is up to 7o deg , check manufacturers data sheet .
Don't forget when building your own temperature device the cold junction calculations that need to be taken into account. Best buy one as this is already done for you and a device required to do this is quite cheep nowadays.
Suggestion: There are different liquids that could be used instead of mercury. The mercury thermometer may pose environmental hazards. Perhaps, colored alcohol/spirit or similar liquid would do almost the same job. These thermometers are very inexpensive.
