[carl zeiss]

hi all,
I am a newbie for pentax camera.
I have just bought a pentax k-m 2 weeks ago,but I don't know why each time I take AA battery out and then reinsert camera to turn on it,it requires me to adjust date and time,I think this is because my cmos battery CR 2032 ( if have as on canon camera,it has a CR 2032 to store infs of date & time ) is out of date.kindly instruct me how to fix this problems with thanks.

[sterretje]

First of all I think that the camera does not use a battery for that purpose. This info is either stored in flash memory or in memory that gets power from a supercapitor.

If it however does have a battery and it's a user replaceble part, read the manual as it should be mentioned in there.

I assume it's a second hand camera; if not, back to the dealer for warrantee swap/repair.

[fanfaron]

I have the pentax k100d and I have the same problem.

mine is a second hand, I assume that's a common problem with pentax.

[Marc Sabatella]

It's a common problem with almost all sufficiently old consumer electronic products.

[c.cc.c]

每次换电池都要调整时间？ 我也遇到过，应该是机身电容没电了。我的办法是使用一下内闪就解决了。

[daringg]

hi all,
I am a newbie for pentax camera.
I have just bought a pentax k-m 2 weeks ago,but I don't know why each time I take AA battery out and then reinsert camera to turn on it,it requires me to adjust date and time,I think this is because my cmos battery CR 2032 ( if have as on canon camera,it has a CR 2032 to store infs of date & time ) is out of date.kindly instruct me how to fix this problems with thanks.

Hi,

I have the same camera with the same problem, except that it is a second hand.

How did you fix your problem? Does it have an internal battery?

Regards,
Darin

[Paleo Pete]

I'm not aware of any CMOS battery in a camera, although one might exist in some I suppose. Every desktop computer I've ever worked on has had one though, but it's a lot more accessible, and I've had to replace dozens. The time stamp is probably stored by means of a capacitor, which acts as a small battery of a sort. The capacitor stores an electrical charge until the circuit needs it. This is why if you open up a TV or a tube type guitar amp and touch the wrong thing it can kill you. They hold very high voltage for a long time, several months.

The capacitor in a camera holds a much lower charge, probably no more than 3 volts. (CR2032 battery is 1.5V I think) The problem is that the capacitor can only hold power for a certain time. If I take the batteries out of any of my cameras for 5 minutes, I have to reset the date. If I swap batteries in less than a minute, it stays put. I usually take less than 30 seconds.

I'm guessing here, but either you're taking too long to swap batteries or a capacitor is getting weak.

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Last edited by Paleo Pete; 10-04-2012 at 07:30 AM.

[Not a Number]

I think the *ist DSLR used a battery for the internal clock. I looked it up once but can't find the information on which models had them again. There is an additional battery cover on the bottom on the models that have them. Pentax replaced the battery with a build in accumulator I believe starting with the K series though it may have been some of the later *ist. According to Pentax support the accumulator will keep time for about 48 hours when charged for 12 hours with a fresh set of batteries.

[Sagitta]

The capacitor stores an electrical charge until the circuit needs it. This is why if you open up a TV or a tube type guitar amp and touch the wrong thing it can kill you. They hold very high voltage for a long time, several months.

I about got knocked out of my chair just going in and mucking with the guts of my old Powershot - and that ran on a pair of AA's. Its not just TVs that can pack a wallop.

[Paleo Pete]

I never would have expected that one...

Fortunately I found out about guitar amps before I went poking around inside mine, I Had to look up some info to find out what was wrong with it and one of the first sites I found had a stern warning at the top of the page. So I've always been very careful. Fortunately my Super Reverb is designed so that it it pretty easy to drain the capacitors. I guess I got lucky when tinkering with my Fender Champ, I replaced the power cord with a grounded one, soldered a bad connection back together, replaced all the tubes, poked around a lot looking for other bad connections (not hard, push the cardboard circuit board with a pencil, it'll make noise) and never got hit...long before I found out what the caps can do...