Changing lithiam battery on Pentax 645

I normally shoot SQAi but for the last four months have had the loan on a friend's Pentax 645. I like the viewfinder and the feel of the camera but not the sync speed with strobe. My question is; does anyone know how to chage the internal battery -i.e. where is it - r does it have to go back to the distributer?

Doug

I think the lithium battery is located under a small, round cover on the bottom of the camera located next to the tripod socket. It requires a little two-pin spanner wrench to unscrew, but you could probably make a tool from a thick paper clip.

As I recall from the literature, the internal battery that runs the meter must be returned to pentax to be replaced. This was one thing that caused me to decide against the 645 and get the 6x7 instead.

The battery is very easy to replace. It is like a computer battery in that it allows the camera to keep things in memory when it is not being powered by the regular batteries. The battery costs about $2 at radio shack. I found a small tool that is used for spreading the retaining clips on auto trim had just the right pin size to remove the lid.I really like these cameras and own two. The battery does not have to be changed very often (perhaps every 5 years if fresh when new).

Went to Radio Shack at mall and bought replacement battery.

Went to the watch repair place (also in mall) and used their "picks"

to open the chamber and replaced it myself. Their spanner would not

fit.

It cost ~$2 and one thank you.