(Webmaster) O.K. here are notes people sent me. This states you can use the "hearing aid" batteries and a rubber washer from a hardware store. These are the "air" batteries, holes in the battery allow air to make power. A hearing aid need lots of power to run the amp. Your light meter needs very little power..... so one I have heard over the years was to only expose 2 or 3 holes in these batteries, not the whole back. The "air" batteries don't last as long, hence the reason they come in "blister packs" of 8 or so.... but again due to the exposing of ALL the holes in the battery. A blister pack in N.J. USA were $8 for 5 in 2002.
CLASSIC CAMERA PAGE ON MERCRY BATTERIE REPLACEMENTS
Mercury Battery Adapter - home made
Link showing the actual replacement batteries
Check this link on a special metal wrap-around for a ZA675
zinc-air battery. This is said to be special for a Nikon Ftn Meter.
E-bay seller with adapters for Nikon, Hassleblad, and other cameras with hard to find batteries.
Posted by Gene Windell on August 05, 1999 at 21:31:12:
In Reply to: batteries for Nikon FTn posted by frank bellows on August 05, 1999 at 18:00:25:
I've tried the Wein zinc-air 1.35v batteries in a variety of cameras and light meters, and they work fine. I've had some last as long as a year or more. My complaint about them is the cost and availability.
One solution is to use zinc-air hearing aid batteries, which are available
from Radio Shack, Wal-Mart, K-Mart, and about any drug store. The kind that have "675" somewhere in the model number
are the same physical size as the old mercury EPX 675.
Don't be thrown off if the package says "1.4 volts." They test out at 1.35 volts. These hearing aid batteries come 4 or 5 in a package, and cost less than $1 each. This compares to $5 or more each for the Wein zinc-air batteries, and I believe they are the same product.
If your old camera used the EverReady EPX 675, the zinc-air hearing aid batteries will fit and work perfectly. If your old camera uses the EverReady EPX 625 (Mallory PX13), you will find the 675 hearing aid batteries are the same thickness, but too small in diameter. Otherwise, the voltage is correct.
About any hardware store sells faucet washers in the plumbing department. If your old camera uses the EPX 625/PX13 mercury cell, take one with you in addition to one of the hearing aid batteries. Tell the sales clerk that you want a rubber O-ring type faucet washer that will slip over the hearing aid battery, and make it same same outside diameter as the EPX 625. I bought some of these recently at a True-Value Hardware Store, and they cost 15 cents each.
The + contact for the hearing aid batteries is on the smooth top surface, and the - contact is on the ridged bottom. The rubber O-ring serves only as a spacer, which keeps the battery in place and prevents it from slipping off the contact points within the battery chamber.
I've tried this, and the hearing aid batteries work great for me.
Link to a site
with Mercruy battery replacements for Minolta cameras.