[geeks] A digicam battery puzzle

[Phil Stracchino]

My wife's digital camera is the Olympus D-500L that I had before I got
my current Canon Powershot Pro90IS.  It's developed a puzzling problem.
 Briefly, it will power up using Energizer photo-lithium batteries or
Duracell manganese alkaline cells, but will not power up with NiMH
rechargeables.

Now, a little testing with a digital multimeter shows that the Duracells
and the Energizer lithiums, both nominally 1.5v, are both putting out
around 1.69v open-circuit voltage, while the NiMH cells (I have
Energizer 1.2v/1850mAh, Energizer 1.2v/2100mAh, and Panasonic
1.2v/2300mAh) are all topping out around 1.43-1.45v, which is pretty
reasonably close to the theoretical chemistry limit of about 1.48v at
maximum charge for a NiMH cell.

"Well, that's obvious," is the first response, "the camera requires 1.5v
batteries, not 1.2v, and won't power up with a niminal-1.2v battery."

The problem is, the camera *came with* NiMH batteries (Olympus branded,
1.2v, 1300mAh), and has worked perfectly with successive generations of
NiMH cells for almost ten years now.  So why would it suddenly stop
working with NiMH cells, but continue to work perfectly well with 1.5v
alkaline or lithium batteries?

(I called Olympus America this morning, and the support tech I talked to
was mystified.  However, I think it's a pretty safe bet he was tier 1
support.  I may call again tomorrow and see if I can get them to let me
talk directly to a tier 3 engineer.)



-- 
 Phil Stracchino                     Landline: 603-886-3518
 phil.stracchino at speakeasy.net         Mobile: 603-216-7037
 Renaissance Man, Unix generalist, Perl hacker, Free Stater