Thanks for all this advice. I located C536 and it was bent over, but looks ok, leads are firm, and there isn't any corrosion. I will check the underside later today, though. I will desolder it and check its values; I think I have a comparable ceramic cap in my collection and can try a substitute. On U503, that IC does have some mild corrosion and tarnishing on the top plate, which my other TA-2A does not have. Perhaps a close inspection of the pins is in order, although at first glance they seem fine, and the entire top board seems fine, in contrast to the power supply board. I will try the depowering/shorting procedure (seems to be my specialty today). And based on prior experience with a battery on a SR-2A, I will desolder from the board rather than trying to take the battery itself out. Thanks again for your help and insights - tack så mycket. It is very kind of you take the time.