I have the ET-732 probe, and they are 6ft in length. I use the "pit" version which doesn't have the pointy end like the food probe, but they both have the same thermocouple and should work the same.
Since I can't attach anything on this forum, wish we could use a forum software that wasn't 20 years old, here is the table of temps vs resistance for the ET-732 probes:
You can use this to see if the probe works at a couple known temperatures. I do room temp, and boiling water temp. If that is working, then the probe is fine. Let's double check your coefficients. For the ET-732 they should be:
The Resist value should match the schematic which should be: 10kohms if you didn't make any changes here.
Sorry to bring up a post over a year old but I just discovered this project a few days ago. I'm excited about it. Thanks to Bryan and all.
But my first question is for dave... Where did this table and/or these coefficients come from? Is there any documentation on the probe? Did you figure out it is some kind of standard probe that has this known info? If so, what kind is it?
I have been working on a similar project and I use thermocouples mainly because I couldn't find this type of info on some inexpensive commercial probes.