Control AC motor speed with mosfet?

[bigone5500]

I am going to start work on a project that will involve a small turntable motor from a microwave. It is rated at 120VAC, 3.3W, .0275A. I want to slow it down a bit so I am thinking that I can control it via PWM through a mosfet of some kind. However, I think that a mosfet will only conduct one way. How can I accomplish this task? I want to use an arduino of some sort to send the pulse to the controller (mosfet?) and use a potentiometer to speed it up or down.

*edit* I just read somewhere about using a solid state relay and sending the pulses to it to control the speed.

Thoughts/suggestions???

Thanks!

 

[(*steve*)]

They are synchronous motors (I believe).

Frequency control will be the effective method.

Perhaps you could pass through every 3rd half cycle. It's something I've thought of doing, but have yet to try it.