I bought a Salton yogurt maker at a yard sale last year; it sounds like your Hamilton Beach model works the same way.
You can use the Salton Yogurt Maker instructions:
A. 1 quart milk - skimmed, fat-free or made from non-fat dry milk.
B. Yogurt starter - 2 heaping tablespoons of plain, unpasteurized yogurt, or previously made yogurt, or 1 package of dried yogurt culture.
1.) Heat milk until it just boils and cool it down to add starter level on the Spoon Thermometer (105¡ F.) My note: The spoon thermometer was missing from my yogurt maker, too. I've been using a regular candy thermometer, and the yogurt turns out just fine - I've never missed the spoon thermometer. I also heat the milk in the microwave using the highest setting, about 18 minutes, instead of on top of the stove (less chance of scorching).
2.) Add 1-1 heaping teaspoons of starter to 1 of the jars, add some heated milk, stir well; pour into pot of heated milk & stir well.
3.) Pour milk into containers. Cover with top and plug in. Set the "Time Out" dial (that's where the 12 numbered settings come in) for 10 hours later to remind you what time the yogurt will be done. For example, if you make the yogurt at 9 a. m., slide the indicator to "7" to remind you that your yogurt will be done at 7 p. m. After done, place jars in refrigerator. The longer the yogurt "incubates", the tarter-tangier it will be; if you prefer it that way, you might want to incubate it for 12 hours instead of 10.
4.) Allow to cool 3-4 hours before serving.
Hope this helps!
Karen