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Mark2000
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Username: Mark2000

Post Number: 1
Registered: 08-2011

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Posted on Wednesday, August 31, 2011 - 05:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

This is for the 124, not the 124G which has a different light switch.

I just got one of these and its in excellent shape. The meter does work, but the switch sticks to off when the hood is opened.

I may be wrong in my diagnosis, but it seems like the switch is a flexible metal strip not unlike a hair clip. When you close the hood it pushed the switch away from contact with the meter. When you open the hood it should snap back into contact and turn the meter on. Right now it stays stuck at off. I have to remove the hood and push it to on. And one know how to fix something like this? I have no idea why the switch is so ridged that it won't spring back to its place anymore.

Here's pictures of it on and off:

http://www.flickr.com/photos/35052427@N02/6100409214/

http://www.flickr.com/photos/35052427@N02/6100409518/
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Mareklew
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Username: Mareklew

Post Number: 231
Registered: 03-2010

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Posted on Thursday, September 01, 2011 - 01:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Yeah, those were unreliable hence the "G" model, that as the main if not only improvement listed getting this switch to work.

If you don't plan on selling it right now, my opinion would be: let it be. The light meter is sort of inaccurate anyway (due to nonlinear response of CdS sensor and this not being a bridge circuit nor a compensating meter it can't be calibrated better than to +/-1..1,5 EV over the metering range).

Been there already with my 124G (switch was OK, just the meter was off).

By the way: this meter relied on mercury batteries, so without recalibration it's gonna be off whatever you do about the switch.

Marek
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Mark2000
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Username: Mark2000

Post Number: 2
Registered: 08-2011

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Posted on Friday, September 02, 2011 - 08:34 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have a replacement Wein battery of the same voltage as the mercury one. That's not an issue. I want the camera functional and there are very differing views on the accuracy of the meter. I'd like to try it for myself.
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John_s
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Username: John_s

Post Number: 53
Registered: 07-2009

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Posted on Friday, September 02, 2011 - 03:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mark I did get the meter on my 124 working by cleaning the contacts with a slip of very fine sandpaper - you seem to think that the contacts are not actually coming together when you lift the hood, can you see that there is actually a gap? The usual problem is just a little corrosion or oxidation, I don't recall any problem with the contacts not physically coming together - although it's a while since I had it apart.
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Mark2000
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Username: Mark2000

Post Number: 3
Registered: 08-2011

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Posted on Friday, September 02, 2011 - 06:08 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

John, thanks for the tips, but what I'm having is a different problem. The contacts are just fine. It's the actual piece of metal the hood flips back and forth. Right now that metal piece is snapping into one position or the other because it seems too stiff.

I have no idea how it should behave normally, but right now it acts like a hair clip: http://bios.weddingbee.com/pics/121334/hairclip.gif . It snaps into one position and then snaps back to the other. So when the hood closes it snaps it to "off". There's nothing in the camera that can snap it to "on" that I can see.
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John_s
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Username: John_s

Post Number: 55
Registered: 07-2009

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Posted on Saturday, September 03, 2011 - 05:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I've had another look inside mine ... the metal part you compare to a hair clip normally rests against the contact with a degree of spring tension. Closing the hood moves it forward to break the contact. It springs back freely when the hood is opened or removed - there is no second "rest" position.

The spring action seems to reside in the curved central part of the "hairgrip" which engages with the slot of what looks like a small screw in the white plastic block. Has this come adrift? Otherwise I can't suggest how to restore the correct action.
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Mark2000
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Username: Mark2000

Post Number: 4
Registered: 08-2011

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Posted on Saturday, September 03, 2011 - 11:03 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You may have helped just enough. At least now I know what the original action is supposed to be. Much gratitude.

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