It might have had something that can shift its frequency.
What happens in most microwaves is you get a standing wave. The high and low parts of the wave are always at the same spot. You then get a hot spot at the peak (and trough) of the wave, and a cold spot when the wave is near the zero node.
By shifting the frequency, even just a little, you can shift the hot spots around and more evenly cook the food.
This is obviously more expensive, and these days you can get it in higher end residential microwaves. Way back when, though, it was only something you’d see in industrial models.
It might have had something that can shift its frequency.
What happens in most microwaves is you get a standing wave. The high and low parts of the wave are always at the same spot. You then get a hot spot at the peak (and trough) of the wave, and a cold spot when the wave is near the zero node.
By shifting the frequency, even just a little, you can shift the hot spots around and more evenly cook the food.
This is obviously more expensive, and these days you can get it in higher end residential microwaves. Way back when, though, it was only something you’d see in industrial models.