I bought a reproduction repair manual from here: http://www.photobooksonline.com/book...ersrepair.html (#8183). It is basically a single speed (1/125) mechanical shutter that has an electronic delay added on to achieve the slower speeds. So 1/60 is 1/125 shutter + 1/115 delay, 1/30 is 1/125 shutter + (1/115 + 1/60) delay and so on (the math makes more sense in decimals than fractions). The speed change is governed by resistance with individual resistors for each speed so that part is repairable.