Re: PHOTO-3D digest 1084

[bobh@xxxxxxxxxxxxx (Bob Howard)]

RE: Wein battery vs true 1.35 Hg battery.
To: Mike K.
  The Wein battery at least in the Popular Photography writeups was
indentified as an air battery as used in hearing aids..but modified
for photo use by making it the diameter of a 625/PX-13 which is it
designed to replace. By coincidence the air battery has nearly the
right voltage. In hearing aid use the short shelf life due to drying
out after the air is "let in" by removing the seal, is not noticed as
hearing aid depleat the battery due to heavy current drain before even
the short shelf life. The light drain in a metering situation means
that the battery might have a 3 months life compared to 1 year for a
mercury battery unused. Now Wein claims to have covered some of the
holes to minimize dry out yet let it function..so perhaps it has a six
months shelf life as a camera battery once seal removed?
I don't see any of this as misrepresentation..just a convenience so
you don't have to make your own adapter. BobH



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