Reddit mentions of WeinCell MRB625 Replacement Battery for PX625/PX13

1. wein cell battery is the modern replacement for this camera although I had mine converted to use a Varta 625 battery when I had it repaired. apparently they last much longer. just remember to switch it off "A" when the camera isn't in use to conserve battery.
   
   
2. I've taken off the top of mine in an attempt to diagnose issues and it was pretty easy to dis and reassemble the cover/film advance leaver. I did not go any further than that. Havent tried to clean the viewfinder or anything either, that might be based on how good of shape it's in and if its worth the effort.
   
   
3. There are a lot of guides on youtube, I haven't tried it but I know you're going to need a spanner to do it.
   
   hopefully some of that was helpful, I know it doesn't answer everything, but it's what I know from my experience. outside of that I'm not sure and wouldn't want to lead you astray
   
   The canonet is a great little camera, a little over hyped but still pretty great, enjoy it!

Why not just buy a modern 625? You can get them in multi packs from eBay sellers too. Not sure I fully understand all the people using the wrong batteries and making notes of meter compensation.

That's a great deal if the camera works. The SRT 102 has a match needle meter system, but you can operate the camera fully manually without a battery in it, as it is a fully mechanical shutter and aperture system.

In terms of what to check for for the SRT-102 specifically.

1. About half way through the production (or early on, I'm not sure of the details), Minolta stopped making them with the mirror lockup option. If that's important for you, make sure the one you're looking at has it.
   
   
2. Check to see if the mirror is stuck. As mentioned, if your model has a lockup, make sure that isn't engaged. If the mirror sticks after shooting, it may be that the bumper is degraded.
   
   
3. Shutter issues - the SRT102 has a cloth shutter, so make sure it's in good condition. If you have access to the camera before buying it, I'd highly recommend you shoot blanks (without film with the back open) to verify the magnitude of the shutter speeds (ie, 1/8 isn't the same sound as 1/250 isn't the same as 1/1000). Also look to see if the entire shutter curtain operates properly.
   
   
4. Check the light sealing, as it may need to be replaced.
   
   
5. Check the depth of field preview to make sure it's smooth and functioning. The SRT-102's works on a toggle. Push the tab in, and it will preview the DoF and button remains depressed. Press it again to release it (kind of like a ball point pen).
   
   
6. If the camera is mechanically sound (shutter is fine, film advance is smooth and not grindy, DoF preview is good) then I'd say 90$ is a great price for it, especially with that Rokkor-X f/1.4 nifty fifty. Is the glass clean?
   
   
7. If you care about the meter, verify its function both by using/bringing a mercury replacement cell and using the "B.C." function on the bottom of the camera. Also look through the glass to see if your exposure is approximately right (use sunny 16 or an external meter to verify). Also, this is a good opportunity to check if the battery terminals are mucky and shitty.

Wein Cell makes a great replacement for the original mercury battery. I'll provide the link below. The battery is the only one that is accurate, and is not too costly. I don't know how long the battery lasts, I hear it usually goes for 3 months before the battery wains. The camera can also shoot fully manual, with no battery in the camera at all. It's very handy for learning to shoot film, and also if the battery runs out you're not completely out of luck. I'd highly recommend the camera, I found it for $70 on eBay in very good condition, only needed new light seals. I love my camera, definitely look into it. http://www.amazon.com/WeinCell-MRB625-Replacement-Battery-PX625/dp/B00009VQJ7

You're looking for the Wein cell.

You just won't be able to use the light metering. I have the same camera, and this is the battery I use. Works like a charm

http://www.amazon.com/gp/product/B00009VQJ7/ref=oh_details_o03_s00_i00

You need something like this. https://www.amazon.com/gp/aw/d/B00009VQJ7/ref=ya_aw_oh_bia_dp?ie=UTF8&psc=1

Yeah, comparing the meter against another camera is a good idea. Is it really so expensive to mail it to the States? I've done crazier things. Sent my Pentax from Texas to Tennessee to have it overhauled, although I guess that's not as far.

As an alternate solution, these Wein batteries are specially designed to output the same 1.35V as the original discontinued mercury cells. They're expensive, though: http://www.amazon.com/WeinCell-MRB625-Replacement-Battery-PX625/dp/B00009VQJ7/ref=pd_cp_p_1

this?
WeinCell MRB625 Replacement Battery for PX625/PX13 https://www.amazon.com/dp/B00009VQJ7/ref=cm_sw_r_cp_api_odbLBbCN9WDAZ

It does! But you're gonna need these mercury voltage equivalent replacement batteries to get the right voltage and reading. Alkaline batteries are 1.5V if I'm not mistaken which will throw off the reading. Everything will work fine otherwise!

Any suggestions for replacing an old mercury px625 battery for a Canonet QL17? So far the best I can find is a Weincell but they're expensive and I hear don't last very long.

https://www.amazon.com/WeinCell-MRB625-Replacement-Battery-PX625/dp/B00009VQJ7

Right off the bat it sounds like your meter may be broken. However, there are a few things to check first before declaring that.

1. Make sure you use the correct battery. As /u/iamthejeff_ pointed out, the OM-1 natively takes a battery that is no longer available. A weincell or a hearing aid battery will give you the proper voltage. You don't 100% need an o-ring to center the hearing aid battery. The cap should do a good job keeping it on the contact tab.
   
   Once you've gotten a battery of the correct voltage you can test the meter again. One thing of note is that the meter movement itself is mechanical. It will respond to the aperture ring and shutter speed movement even if the meter itself is dead. The meter only reads from around 2EV to 17EV so make sure you test this in sunlight to see if the meter is actually functional. If you're in a lit room it's possible that the meter simply isn't sensitive enough for the light in the room.
   
   
2. If you have a regular OM-1 not the n or MD variant (though I think this MAY apply to some MD variants, I can't recall) then you can also take off the bottom plate by removing the 4 bottom screws and check the battery contact screw. On early models this was made of nylon and is easily broken. This can cause improper electrical contact and make the meter appear inoperable. If you have an n model they all used metal screws so this wouldn't be the case.
   
   If all of this checks out and the meter is inoperable then I'd say it's pretty safe to call your meter dead. If you have an interest in reviving the meter you can send it to John Hermanson to do a CLA on the camera. I'm pretty sure he can replace the meter cells.
   
   His website is here.
   
   However, given your circumstances that's probably too slow and too expensive.
   
   
   You can also simply use the camera without a meter. It's a mechanical camera and doesn't need the meter to take photos. You will simply need to employ an external light meter or use Sunny16 or similar exposure rules.
   
   If a light meter in-camera is a must then buying another OM-1 is quite cheap on eBay.
   

What exactly do you mean contacts in the case?

And here’s the amazon link

WeinCell MRB625 Replacement Battery... https://www.amazon.com/dp/B00009VQJ7?ref=yo_pop_ma_swf

I can’t speak to the F3, but I love my Canonet. I have an earlier model QL17 with a 45mm lens. I have only used the wein cell battery and my light meter has been very accurate. I usually point towards the ground to meter for shadows and then manually set my exposure.

Previously, I have only shot on canon DSLRs. I have really enjoyed working with a rangefinder. I did a first impressions post in the rangefinders subreddit and all of my posts on analog have been from my Canonet.

Just my 2 cents!

Bought this off Amazon, works pretty well.

You'll need a 1.35v mercury-equivalent replacement battery, and not just something you pick up at Wal-Mart. Weincell makes a good one.

Why, the internet of course! Wein makes them and they work - I've got one working in my Nikon F right now and it's been there for years.
Here, or here, or here.