In article ,
"Phil Allison" wrote:

Sine waves of the exact same frequency and amplitude can ONLY differ only in
phase.

A 180 degree phase difference is as good as any other.

Phil-

I have a flashlight powered by a two-phase system - two D cells. It
certainly fits your criteria. Its power system can also be considered
AC, since DC is just AC with frequency equal to zero.

Facts are no deterrent to a persistent troll!

Fred