[LargeFormat] more on batteries

[Clive Warren]

At 13:58 13/12/00 -0800, Don Wilkes wrote:
> >>http://www.acecam.com/magazine/battery1.html
>
> >The URL above did not work for me.
>
>I don't know what to suggest, Clive; I just clicked on the link as
>presented in your reply, and got to the appropriate page immediately.  It's
>an older article, but still reachable through the index.  Try this:
>  Go to www.acecam.com
>  Click on "magazines"
>  Click on "Archive" from the list on the left.
>  Under product reviews, look for: "MR-9 Battery Adapter saves old cameras
>from..."
>That'll be it.
>
> >A quick recommendation - I bought a silver oxide battery to mercury
> >converter a while ago.
>
>Ah -- this must be the MR-9 or equivalent.
>
> >replaces PN625, PX625, HD625, RM625, 4625, H-D and MR9 1.35 Volt
> >batteries.
>
>Varta still makes the PX-625, according to this article:
>
>"Varta in Germany continues to manufacture mercury photo cells, according
>to a recent visit to their web site. Some recent postings in newsgroups
>indicate there are Canadian mail order sources for mercury batteries.
>Mercury batteries are still manufactured in Asia and Europe and will
>continue to be available there for the foreseeable future. (Availability is
>subject to change at any time.)"
>
>If you have further trouble accessing that web site, let me know, and I'll
>grab the whole text and forward it to you, Clive.
>
>All the best,
>\don

Hello Don,

Thanks for the follow up and the kind offer.  The server must have been 
down when I tried the link before as it is now working perfectly :-)

The text in the article is a great overview of the current situation on 
mercury oxide batteries, however does contain a few factual errors.

Varta stopped selling mercury batteries a long while ago - they have a very 
"green" government right now. Also, the sale of such batteries is banned 
throughout Europe - except the UK :-)

The only source that I know of is Asia for new mercury batteries - all 
Varta mercury batteries being sold now are around two years old from the 
last manufacturing run.  If kept in a fridge they should have a shelf life 
of at least five years and probably a lot more.  Freezing them is a really 
bad idea as this damages the electrolyte.

The MR-9 is indeed the converter that I was referring to. This is a 
well-made device and does the job, however the Shottky diode inside which 
does the voltage conversion from the silver oxide battery 1.5v does not 
match 1.35v exactly.  Will have to look up the exact figures.  So, the 
bottom line is that the MR-9 is probably the best bet unless you have 625px 
batteries in the fridge - I have both :-)

You can do your own conversion using a Shottky diode if you are happy about 
opening up a meter and wielding the soldering iron to place the diode in 
the power supply lead to the circuit board in the meter.  You would also 
have to change the size of the battery compartment to suit the smaller 
silver oxide battery.

All the best,
                 Clive   http://www.f32.net
                         Large Format Travel and Stock Photography