Pentax MX meter problem

Discussion in '35mm Cameras and Accessories' started by GRHazelton, Aug 22, 2010.

  1. GRHazelton

    GRHazelton Subscriber

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    So far an APUG forum search has yielded nothing useful. My MX has developed an insatiable appetite for cells to run the meter. Even after service by a well-regarded Atlanta area company new cells last only a few days, rather than the 12 to 18 months they did in the past.

    I've removed the bottom plate and the tiny switch which turns on the meter via the shutter release seems to work, according to my digital VOM. Does anyone have any suggestions before I ship this beauty off to Eric for service? Many thanks!
     
  2. Les Sarile

    Les Sarile Member

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  3. Pumal

    Pumal Member

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    many tines is just a little capacitor to change
     
  4. Andrew K

    Andrew K Subscriber

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    When I was repairing cameras most MX problems were caused by the switch on the bottom. Could the switch be earthing to the bottom cover when the cover is put back on? With the bottom cover fitted is the meter activated when the shutter button isn't being pressed - this would indicate a meter short?

    It is very unusual for one of these to be draining batteries....my other suggestion is to remove the top over and make sure none of the wires etc is crushed...
     
  5. GRHazelton

    GRHazelton Subscriber

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    Many thanks for the suggestions.

    Les, looking over the link you furnished I don't think I want to go that route. Andrew, that's an interesting idea, however; the meter "seems" to turn off, that is the LEDs don't show. If current is still sent to the meter cell that might explain the drain. I wonder if a bit of vinyl adhesive tape to the inside of the bottom cover where the switch might contact it would be worth a try. Hmmm, it'd be only yet another couple of cells shot....
     
  6. mawz

    mawz Member

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    It's a known issue with the MX's, I had the same problem with mine. On/Off switch issue, the meter gets turned off but not fully.
     
  7. Andrew K

    Andrew K Subscriber

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    From memory it is a known fault - I think the contacts get soft(bend) with age - the switch needs re-adjusting - this should fix the battery drain..

    And plastic tape on the bottom cover won't hort :smile:


    Cheers
     
  8. GRHazelton

    GRHazelton Subscriber

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    Again, thanks to all. I'll try the tape and an adjustment of the switch.