PX-13 PX-625 battery adaptors

Who can recommend a really good battery adaptor for PX-13 PX-625 batteries? I have a Lunasix 3 meter, and I have some zinc air batteries I could use when the last of my mercury batteries die, but I would prefer to buy the adaptors once, and be able to buy the easily available 1.5 volt batteries when I need them. Also, please recommend a source for the adaptors.

Thanks!

There aren’t many options. CRIS is one US supplier of a Japanese-made adapter. On eBay there is a Japanese supplier. Both same price. If you search eBay enough there is a supplier in Thailand at a reduced price. Most offered on eBay are cell holders only that do not do voltage reduction. Shop wisely.

I can vouch for both the CRIS product and their reliability based on a recent purchase.
https://shop.criscam.com/

Note, for Luna-six you will need 2. In my Luna-Pro used the Gossen adapter but those don’t seem to have been available for many years.

BrianShaw said:

There aren’t many options. CRIS is one US supplier of a Japanese-made adapter. On eBay there is a Japanese supplier. Both same price. If you search eBay enough there is a supplier in Thailand at a reduced price. Most offered on eBay are cell holders only that do not do voltage reduction. Shop wisely.

I can vouch for both the CRIS product and their reliability based on a recent purchase.
https://shop.criscam.com/

Note, for Luna-six you will need 2. In my Luna-Pro used the Gossen adapter but those don’t seem to have been available for many years.

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If you read product description closely, watch for the key words 'convert Voltage'. Many of the non-Voltage converting units can be visually identified in their product photos by the presence of a tiny air hole to permit air entry to the air cells, and their discriptions might say: "this adapter cannot increase or reduce voltage."

My Lunasix 3 serves as a backup meter, so for me the mechanical adapters that merely convert the physical size of hearing aid (zinc air) batteries make sense. I can pop the adapter + battery out of the meter when I'm not using it, discard the really inexpensive batteries and store the empty adapter with half a dozen unopened hearing aid batteries, ready to go.
In quantity, the hearing aid batteries are about 60 cents each. In addition, they are easily found (at slightly higher per unit cost) in local drugstores and many other locations - including hearing aid stores.
If the Lunasix 3 was my everyday meter, I would most likely prefer the adapters that convert the voltage from silver oxide cells. That was what I used for an OM-1n. The local, everyday availability of the hearing aid batteries does however make the other approach attractive.

There were instructions online for making your own. Basically, cannibalize a 625 battery and add a diode for the voltage conversion.

There's a 3D printed holder on Thingiverse.com https://www.thingiverse.com/thing:4368708. (and other versions) You have to source a suitable diode (about $0.10 each) and it is finicky to get the wires sorted out, but lets you use an SR44 size battery. There might be an issue with tight battery compartments doing this sort of assembly, but it might be worth the effort.

I acquired some MR-9 adapters from C.R.I.S years ago, and they have met all my needs so far (Olympus OM-1, Soligor Spot Meter, Rollei 35).

grahamp said:

There's a 3D printed holder on Thingiverse.com https://www.thingiverse.com/thing:4368708. (and other versions) You have to source a suitable diode (about $0.10 each) and it is finicky to get the wires sorted out, but lets you use an SR44 size battery. There might be an issue with tight battery compartments doing this sort of assembly, but it might be worth the effort.

I acquired some MR-9 adapters from C.R.I.S years ago, and they have met all my needs so far (Olympus OM-1, Soligor Spot Meter, Rollei 35).

Click to expand...

Interestng. I went back through some old files. One write-up went into a fair amount of detail as to the choice of diode. Basically, the choice of diode will vary based on the current need of the device. It has detailed instructions for making your own from a drained 625 alkaline cell.