OM10 meter inaccurate

Discussion in 'Camera Building, Repairs & Modification' started by tkamiya, Aug 3, 2010.

  1. tkamiya

    tkamiya Member

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    I have an Olympus OM-10 without a manual adapter. This camera was recently purchased off classified and light seals were replaced (by me). I am finding metering is inaccurate.

    This is what it is doing:

    1) the actual shutter actuation itself seems to be fairly accurate
    2) meter indication in the view finder is way off
    . when it should read 1/100th, the meter indicates somewhere around 1 second
    . if I move the ISO setting or aperture ring, it moves accordingly
    . if I play around, sometimes and rarely, it displays correct setting
    . if I take the lens off and move the aperture slider inside the mount, indication moves
    3) it is NOT the battery. replacing them with brand new and correct ones did not resolve the issue

    Reading the repair manual, it seems, on this model, metering circuit and its sensor AND the actual shutter assembly are separate circuit. The actual shutter circuit has an independent sensor. This body is acting as if the metering sensor is not receiving enough light. I believe this is a CDS atop prism assembly.

    I know there IS a known issue with this camera where shutter actuates at slower speed than the indication. This is not the case. It is backwards.

    Any idea would be appreciated. It is not worth the cost to send it to CLA.
     
  2. John Hermanson

    John Hermanson Member

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    CDS cell next to eyepiece is probably bad, or solder connection is cold. John
     
  3. tkamiya

    tkamiya Member

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    That makes very good sense. Looking at the manual, it seems (looking at front of the camera body) it is RIGHT of the penta-prism and it has two wires going to a small board in that area..... I'm guessing cold solder joint.
     
  4. tkamiya

    tkamiya Member

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    I've taken the top cover off and visually inspected (under a microscope) the joint of two purple wires from CDS. It is not the cold solder joint at the CDS/board connection.... Few times, I did manage to get a proper reading so it is still looking like a bad joint of some sort somewhere.
     
  5. John Hermanson

    John Hermanson Member

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    You'd have to resolder the connections. If not that, then cds cell itself is probably bad. John
     
  6. tkamiya

    tkamiya Member

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    I was in electronics field for many years. I can usually tell by visual inspection. I also did re-solder few suspect joints. At this point, I have to conclude, the problem is the CDS itself.