I want to know if the way my microwave works is 'normal' or not. Here's the deal, when I set it at 50% power, it doesn't go to 50% power, it goes to more like it's 100% power for 50% of the time set. For example, if I set it for 2 minutes at 50% you can hear the 'power' kick in for maybe 15 seconds, then it sounds like it goes to no power for 15 seconds and repeats this until the 2 minutes is up. Is that how they all work? And is that really the equivalent at say having a 1000w microwave working at 500w for the 2 minute duration, even though it's 1000w for 1 minute?