Ron,
When you buy gensets for this purpose, look for gens with a Total Harmonic Distortion of less than 5%. It is not so much the voltage but the wave form that messes up modern electronics. The cheaper Colemans can have an actual Square wave, or even a half wave rectifier on them that will not allow the semi-conductors to semi-conduct.
Also, don't try to charge a battery with them IF it works, it takes HOURS to do any good at best.
