In the 70s & 80s, we used Japanese electronics in the US and US electronics in Japan with no difficulty. I remember my dad had a transformer, but I also remember it sitting unused in a closet - I have no memory of it ever being used. I currently have a Japanese-market Space Echo that I use here (though sparingly). But the burnt-out F-2B is the cautionary tale - I am NOT encouraging anyone to ignore the voltage differences!