In article ,
Mark Mallory wrote:

Originally, it ran off a single AAA battery (1.5v) I tried adding a second AAA
in series... Wow! The increased voltage (3v) totally transformed the thing.
The display was now crisp and sharp, it now kept good time, and the buttons now
worked reliably.

Maybe it was designed to run off of a ~3.2V lithium cell?

--
Ben Jackson

http://www.ben.com/