Hi Miss Fitch--McCord is right--
Walmart is the way to go. Look for the Acu-rite digital thermometer/hygrometer combination (if
TSC has Acu-rite, that's fine too--but I can't speak for any other brands--they can vary widely in quality). It will run between $6 and $10. You will set it on the floor of the incubator, behind the turner, where you can see it from the windows. There is room in the back or on the sides for that--it will sit upright, not on its back. You'll understand once you have the thermometer.
Do it tonight, and calibrate the hygrometer portion before you use it. To do that, run a search on this forum for "calibrate hygrometer" and follow the instructions. You want to start it tonight because you'll need to leave it in the plastic bag for several hours--overnight will be fine.
You still won't know how accurate your thermometer is, but usually they're close enough to work. You'll adjust your temps after each hatch according to whether you got a satisfactory hatch or not, and whether it was late or early, but for now you don't need to worry too much. Just trust the thermometer for the time being.
If your eggs are being shipped, they will need to sit for 12-24 hours outside the incubator before you set them anyway, so you still have time to get everything stabilized.
Post again if you have questions. I can probably get a picture of the thermometer I use, which is the one I'm recommending, but I don't have the turner in at the moment because I'm on Day 18, so you still won't see how it sits in there with the turner.
By the way--does your Hovabator have the circulating fan? If so, your temp will be different than if it's not. I love my Hovabator--it holds temps VERY well.
Good luck!
