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02-02-2014, 12:51 PM   #1
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Finally got my Spotmatics working - just needed a battery!

My Spotmatic and SP500 are up and clicking. One thing that has been holding them back was the lack of a battery for the meter. I discovered that my local Batteries Plus store has a huge stock of 387S batteries which fit almost perfectly in the battery compartments. The 387S battery is actually a 394 battery in a black plastic sleeve. I added a bit of tin foil in between the batteries and the battery caps. It looks like the battery surface in both doesn't protrude up high enough to contact the caps.

I loaded some expired Kodak 100 Tmax film into the SP500 and now I'm testing it. It's all I had on me so the Spotmatic is sitting empty.

The SP500 seems to be working just fine except the film advance sometimes sounds like a gear is skipping or maybe the teeth on the film advance spool are skipping. My Spotmatic seems to work mechanically except for the 1s shutter speed and the delay action release lever is stuck.

I'm really excited about the SP500 camera because I it came in NOS condition, complete with the lens, original packaging, etc. The only ding is that original battery leaked and it corroded the entire compartment real bad. Someone tried to remove the compartment with a screwdriver and the screwdriver must have slipped. There's a long scratch on the underside of the body. My Spotmatic has been much loved. The battery cap has a worn slot and is extremely difficult to remove. I have to put something inside the two little holes that sit in the slot.

I'm thinking that if both of these cameras work fine otherwise I should get them CLA'ed.

One thing I have been wondering about is how the metering circuit responds to a 1.55V battery vs. 1.35V battery. I understand that the circuit is basically a current meter that measures current being split between two paths. The needle points to the center when the current in both paths is equal. Even though the current is equal isn't it higher due to the greater potential of the 1.55V battery vs. the 1.35V battery? It makes me think I need to kick the ASA ring up a notch to compensate.

02-02-2014, 01:11 PM   #2
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QuoteOriginally posted by 6BQ5 Quote
I added a bit of tin foil in between the batteries and the battery caps. It looks like the battery surface in both doesn't protrude up high enough to contact the caps.
Congratulations. The foil should not have been needed since the 387S is a direct replacement. You might want to carefully pry the contact up a little. It has likely been depressed from use of the wrong thickness battery coupled with wads of foil

There is some discussion regarding voltage and the metering circuit. The camera has a modified Wheatstone bridge that should be resistant to voltage differences, but the circuit is not quite balanced. What that means in practical terms is not clear to me, though I have done meter comparison using the 1.55v battery with several other bodies with good agreement.

Steve
02-02-2014, 01:35 PM   #3
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If you are really worried about the voltage, get a C.R.I.S. Mercury battery adapter.

CRIS Camera Repair and Services - Mercury Battery Adapters
02-02-2014, 06:29 PM   #4
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I am excited for you. It is always great to hear when an older camera is brought back to life and use

02-02-2014, 08:59 PM   #5
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QuoteOriginally posted by boriscleto Quote
If you are really worried about the voltage, get a C.R.I.S. Mercury battery adapter.

CRIS Camera Repair and Services - Mercury Battery Adapters
The nice thing about the CRIS adapter is that it replaces the battery cover! Yep, you read right. That often scarred and unusable cover that is virtually impossible to replace now has a reasonable replacement.


Steve
02-02-2014, 09:05 PM   #6
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QuoteOriginally posted by stevebrot Quote
The nice thing about the CRIS adapter is that it replaces the battery cover! Yep, you read right. That often scarred and unusable cover that is virtually impossible to replace now has a reasonable replacement.





Steve

I wondered just how well that CRIS adapter fits. Does it fit flush with the camera body?

I'd love to get a new battery cap but $40 seems steep especially when I consider that I can get another Spotmatic in minty cosmetic condition for much less than that just for the cap. But then I'd be creating a hole that I will never fill.
02-03-2014, 07:30 AM   #7
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You really do not need the adapter, like steve said pry the bottom contact up carfully and you shoul dbe good to go

02-03-2014, 08:09 AM   #8
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I'm not worried about what it takes to make contact - prying up the tab. What worries me is the worn coin slot. Cosmetically it looks awful. Functionally it is more difficult to twist the cover open than it should be. A new replacement would be excellent!
02-03-2014, 09:16 AM   #9
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I see, sometimes you can finde them on Ebay
or you can buy a "for parts" camera and get it from there
02-03-2014, 09:48 AM   #10
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QuoteOriginally posted by titrisol Quote
I see, sometimes you can finde them on Ebay
or you can buy a "for parts" camera and get it from there
The problem is that the caps on most parts cameras are in poor shape too or have already been scavenged.


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02-03-2014, 10:21 AM   #11
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Are those made of Aluminum?
would alminum work for a cap?
02-03-2014, 01:52 PM   #12
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I was thinking they were made of brass. I would guess you want to avoid dissimilar metals to avoid galvanic corrosion (if that's the right term).
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