Honeywell Pentax 1 / 21 Spotmeter

I have acquired a Honeywell Pentax 1 / 21 Spotmeter. What batteries that are made today will work? Thanks!

I used to use zinc-air hearing aid batteries in mine, with a wad of foil to fill space and make contact in the battery compartment. Voltage is just right (1.35 V), but cell life leaves a little to be desired (however, if you can get them somewhere like Costco they're quite cheap).

More recently, I bought a PX625 converter -- uses a small 3V lithium coin cell and regulates the voltage to the required level. It limits current too much for the dial light to work, but cell life ought to be very good.

I got a converter, as Don mentioned, and have been satisfied. I got mine from http://home.myfairpoint (dot ) net~snowleop/merc/640index.htm. It was designed specifically for the H/P Spotmeter. Or you can find them via google searching for "PX640 bettery replacement".

Yes, I stand corrected, that's a PX640 converter, not PX625. I got this one as well: http://home.myfairpoint.net/~snowleop/merc/640index.htm Same site has some other interesting converters as well.

thanks!