Grumpy_Mike:
but theres not too much running aroudn in these forums about 120VAC electronics.
That is because playing with mains when you don't know what you are doing is dangerous and can be fatal. I am surprised a teacher has given you this to do with so little knowledge of electricity. I would first check that your teacher is fully insured for when your parents try and sue over your death.
I would use a SSR solid state relay and turn it on and off at regular intervals to control the power. Get a relay that is rated at a current at least twice that you need to switch. The ratio of the on time to the off time determines the power. The code looks exactly the same as the code to flash an LED.
Perhaps I should note. This isn't an actual project. Its one of those kind of, end of semester. "Here go with this info and figure out how to do something like this". And get some xtra credit for doing a short essay about how you would do it. On of those deals. My teacher loves doing them. SO i figured I'd ask here, then over the weekend go find the guy who did my house's wiring and harass him for an hour. Basically what i had already was a relay controlled off of a switch, to turn the "heating units" off and on. But as far as temperature controlling. I understand its 1 thing to switch them on and off at certain setopints to keep the temp near constant. But with adjusting their output like a dimmer for lights. I'm sure there's more going on in a dimmer switch for lights in your house then just a potentiometer, so curiosity got the better of me and I didn't feel like waiting to ask the electrician so i threw it up here.
Gonna go up into the first statement and edit it stating its not actually something to build, shoulda probably mentioned it in the first place. However as it does stand. It seems a bit easier in the forums to get responses when asking about something that's over your head then for hypothetical projects.