My roommate is currently using an ultrasonic humidifier which does not have any means of turning it off when the room reaches the humidity level he wants. Is there any product out there that can be added to the humidifier to do the job. Or do I have to create my own? I ask in this forum because I want to be able to create a portable humidistat, which would be similar to the timers people use to turn lights on and off. Basically I want to have the humidistat where I can plug it in to an outlet, then plug the humidifier into the humidistat, so that when he slides the lever it will turn the humidifier off at a certain level. Can anyone help?