
This is a 500VA, 20 kilogram AC power isolation unit. It is made in Japan (100VAC) and has 100V in, 100/117V out. I'm curious as to what is going on in this unit but due to my limited knowledge there is a lot that's going right over my head as I look at this image. Can anyone give me an idea of what's happening here?
Here is a picture of the backside (the front just has an on/off switch):

By the way, I'm told this unit's transformer has considerable self-noise . . . I'm guessing it could use a good dipping in something to quiet it down. Not much point in having a nice quiet electrical system if the price is keeping a hive of angry bees in your listening room . . .
Thanks!
Chris