Questions about running off of generator

[Thurman]

I have an opportunity to attend a three-day ATV rally type thingy. There will be NO hook-ups of any type so this will be strictly boondocking. I have a Troy-Built 6500 watt generator which I believe is 6500 watt start-up and 5000 watt constant running. But--I have no idea about the sine wave(s) that it produces. I have read so much about certain RV appliances and/or electronic stuff within RV's that don't like to run on pure sine wave or modified sine wave or something like that. An electronics friend of mine states that he has never heard sine wave patterns stated like that. He says there are modulating sine waves and square sine waves. I have no idea. How does one tell which type sine wave(s) that a generator puts out?