I thought there are 2 versions of this Panasonic, older one with "Silent Mechanism" written on the door, and bigger font "Silent Mechanism" and smaller "Twin Motor Rotor" inside. And never one with "Twin Motor Rotor" written on the door and inside, without "Silent Mechanism" written at all. But there is maybe* a 3rd version (probably between both, that would make it 2nd one) with "Twin Motor Rotor" written on the door and bigger font "Silent Mechanism" and smaller "Twin Motor Rotor" inside. * maybe - there is possibility that door was changed by technican, but I've seen pictures of 3 of them - one I have - that would make it unlikely.
Do you have both versions ? Is there any difference inside ? (at least on the visible part of PCB) I have never seen the one with "Silent Mechanism" written before, but the other one I have seen many times. At first glance, they look the same apart from the markings, but there may be other differences.
The back cover is slightly different, has indent in the down right corner. I know that some versions of Panasonics had the D letter (S1 and S1D) or slightly different motherboard parts (S15 and S15 II, i'm not sure if it was called D). Can't find service or user manual for S35, so I don't know for sure if it has any different parts too. Maybe Panasonic cheapened in 1991 (for production) their walkmans too, like Sony since 1988. I can't see a reason to make different version of same walkman if there was no gain.
