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Wayne
Rating: N/A Votes: 0 (Vote!) | Posted on Thursday, February 23, 2006 - 09:05 pm: |
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I've recently acquired a Yashica Electro GSN which looks to have seen very little use. The old battery was very corroded, so the battery compartment required quite a bit of cleaning. I then did all of the typical things to get it working - replaced the negative wire and the 'pad of death' (which had completely disintegrated) - but I'm still having some problems. In auto mode it works fine and seems accurate except for f16; for longer exposures (say more than 1 second) the shutter stays open at this aperture. It closes if I turn the ring to f11. Long exposures are also correctly timed for f11. The slow/over lights also work correctly. In B and flash modes the shutter also stays open and won't close unless the dial is turned back to auto or the advance is moved until the 'Yashica clunk' is heard (ie. shaft is released from the down position). I've cleaned all of the contacts in the lens barrel, but this hasn't made any difference. I managed to replace the 'pad of death' by just removing the top plate as others have described (rather than removing the whole lens barrel etc). I'm wondering if some of the gunk from the disintegrated pad of death is contaminating the contacts below, and whether this could cause the symptoms I'm describing? I've sprayed contact cleaner in there from above and below to no avail. My other thought is that it's a voltage related problem and that there's still some resistance somewhere due to corrosion from the old battery. The Electro is perfectly usable as is, but I'd certainly like to sort out these quirks if possible. Any thoughts would be appreciated. Cheers Wayne |
Winfried
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, February 24, 2006 - 12:06 am: |
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In your case I would suspect that one of the resistors on the resistor bank (on a small pcb board under the aperture ring, it has some slide contacts, too) is faulty. I think Roger Provins has provided the meter schematics, you can check the proper value of this resistor on his site and test it with a simple digital volt meter. |
Wayne
Rating: N/A Votes: 0 (Vote!) | Posted on Sunday, February 26, 2006 - 05:33 pm: |
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Thanks for your reply Winfried. Are you referring to one of the resistors in the board which selects for f-stop via slide contacts? Would the f16 resistor be the most likely culprit? Could this also be responsible for the shutter remaining open in the B and flash settings? Sorry for all of the questions but my electronics knowledge is fairly limited. I'll look up the values on Roger's site and check them with my multimeter. Cheers Wayne |
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