[NTLK] OMP Battery Tray Conversion

Andrei Chichak newton at chichak.ca
Thu Nov 27 02:03:02 EST 2014

The 1x0 will charge the NiCd batteries by simply binding the two inner cells together with a piece of cello tape. I used this method starting when I got my clear 110 in ’94.

The Notepad/OMP/H1000 used NiCd batteries as well. NiCd cells use a different charging regime. They are charged more slowly and the end of charge is detected by a final dip in the cell voltage. In the 2K series, NiMH batteries were used and the end of charge is detected by a rise in cell temperature. Therefore the OMP has no need for a temperature sensor for charging (it has one for auto-contrast adjustment).

To charge batteries in an OMP, since I can’t find mine at the moment, I would look for the NiCd pack detector switch and figure out how to engage it with your tray in place. Perhaps your biggest chore will be finding AAA NiCd batteries, I’d suggest Digikey.


> On 2014-November-26, at 23:10, Woody Smith <woodysmith at me.com> wrote:
> I don’t know about the OMP but the rechargeable pack in the pack in the 1x0 was just 4 NiCad cells held together by two contoured aluminum sheets glued to the cell. The aluminum held down the switch.  A few folks used a piece of stiff paper to accomplish pressing and used rechargeable cells.
> Woody
>> On Nov 26, 2014, at 10:53 PM, Greg Hankins <greg at greghankins.com> wrote:
>> Some time ago, Frank wrote this:
>> "... it is very easy to convert a standard alkaline battery holder into something that the Newton will recognize as a rechargeable pack. This takes only a fraction of the time and has the additional benefit that the cells can henceforth be replaced in almost no time."
>> I'd be grateful for thoughts on how to accomplish this. Having recelled an eMate battery pack, I am familiar with the gizmos (technical term) used in that unit to prevent overheating. Are similar sensors a necessary part of converting the OMP battery tray to a rechargeable unit? What sort of rechargeable cells would be recommended?
>> Thanks!
>> Greg
>> -- 
>> Greg Hankins
>> Town Creek, NC
>> Mailed from my MP2000+
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