n 1975, Minolta "upgraded" the original SRT100 series to the SRT200 series. Actually, there was very little difference between the two series of cameras. Perhaps Minolta felt that the SRT100 series name was getting too old and that the public wanted something "new". After all, the early 1970's saw dramatic competition in the camera market, and other camera companies were producing "new" cameras with new names -- some with very minor changes. For example, Nikon added a hot shoe to it's Nikkormat FTN in 1975, and called it the Nikkormat FT2. In the same vein, Minolta made some minor changes to all of the Minolta SRT100 series cameras -- and the SRT200 series was born.
The SRT200 was a modified version of the SRT100. There were actually six versions of the SRT200, depending on the market, with slight variations over time. The model numbers are not inscribed on the cameras.