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Author Message   John Rating: N/A Votes: 0 Posted on Wednesday, March 02, 2005 - 02:54 am:    Right! I have spent so much time on this and it's still two steps forward, three back! Following advice here and on the rangefinder forum, I have now checked the shutter blades (clean & dry) and resoldered all the connections on the resistor chain connected with the aperture ring. Yes, stupid boy, I forgot that I can't measure resistance while the part is still in circuit (doh!). Anyway, since f16 was causing the problem, logic suggested checking the last resistor in the chain. I removed it and it measures 1.14 Ohms (so what?). I substituted a piece of plain wire to see if it made much difference to the f11 shutter speed - interesting! At a 2 second exposure @ f11, I now got around 3 seconds @ f16, probably explained by the fact that the resistor value is relatively low anyway. So resistor back in and I get 4 seconds - whoohoo! This sets me to thinking and I decide to check the solder joints on the pc board with the (already) replaced capacitor on. Lo and behold, one or two dry joints and the capacitor has a small crack at the top of the -ve leg. Next move is swap the capacitor, but it is unmarked - following conventional wisdom, this is usually 2.2 or 3.3 microfarad. Tried both these values, but ended up with a completely random shutter (arrgghh!), so original back in until I can get some other values to try. Wait a minute! It's all working PROVIDING I have all the screws in that hold the meter circuit in the body - wow! (I wonder if there is a return path through the frame?) So I put it all back together and give the shutter a good few dozen tries at different asa figures and the difference between f11 and f16 is just about double every time - go to bed a happy boy. Wake up this morning and show her indoors how clever I am only to find that the shutter is as random as ever (grrr!). So I'm back to square minus one! I'm starting to think that the IC is dodgy and only works correctly when it is warm - ie above a certain temperature - this is backed by the fact that the loger held the body this morning, the better it worked. Anyone got any bright ideas?