Something happened that reminded me of this tonight, and I think I have finally made sense of something seen as a kid. For some odd reason it just hit me. When I was fairly young and living in the Los Angeles area, there was a test done one night on a local TV channel that was supposed to produce a color picture on the black and white TVs commonly in use. And I can recall seeing some color; I think mostly green. From time to time I have thought about this and wondered what it was that I saw. In fact at times I have doubted the memory as it didn't make any sense, but I can remember the event very clearly. Tonight it occurred to me what they were probably up to. I bet that they were strobing the white to produce a false color image, as is done with alternating black and white dots on a rotating wheel [I don't recall the name of the effect]. The idea is that each pixel on the screen would be strobed at the frequency required to produce the desired color for that dot. Does this make sense? I'm not sure what the strobe rate is that produces the false color effect, or if this was doable on B&W televisions, but it is the only thing that has even threatened to make any sense here. Is there any other way that one can imagine producing color on a B&W screen?