My Son picked a 1st generation Yamaha inverter a 900 or 1000 watt unit for various lite load camping applications , it was a trade on an old chainsaw . Was & still is great on fuel however the economy mode is annoying . The 1st nite he left it on & woke me up around 2 am with its constant governor surging lol. I put it on normal mode it picked up a fast idle then settled into a constant low him . After that we only ran it on economy mode during the day when the kids wanted to watch a movie or auxiliary lighting etc . Until early this spring when I found the problem was with the governor spring assembly !