[NTLK] 2000 battery pack temperature switch

[Forrest Buffenmyer]

Hello Sonny, it’s great to hear from you again. How have you been? I hope your family is well.

Christian,
In the limited experience I have in rebuilding MP2x00 battery packs—attempted 6, successfully completed 4—I learned that there are two things you MUST have to complete the job successfully (which is why my first two did not go well): the thermistor and the temperature switch. The former is the taped piece between the two cells; the latter is the “sticker” looking thing on the bottom that connects the two “stacks” of cells (probably what Sonny calls the Polycell fuse). Without either of these the battery pack will not work properly—or at all (and yes that’s why my first two did not work). Without both—well you get the idea. I don’t know what you have there, but it doesn’t sound like the thermistor. You’ve been to Frank’s site, so you know what one looks like.

If it were me I would probably ditch the one you have and get another through eBay or similar—if you are in the US I could mail you a couple of old packs I kept that I will likely never rebuild, because as I think I mentioned before I now use NiMH cells in the AA battery sled. I also have some spare thermistors and Polycell fuses I could send, so you could complete the one you are working on, for just the cost of postage. Likely the easiest and cheapest method would be the latter choice. Send me a direct email if you’d like.

Mahalo,
Forrest

Sent from my iPad Pro 9.7"

> On Sep 25, 2023, at 4:53 PM, Sonny Hung <sonnyhung at gmail.com> wrote:
> 
> On Mon, Sep 25, 2023 at 4:46 PM Christian Burk <omahane at gmail.com> wrote:
> 
>> Hi.
>> 
>> I was following these steps (
>> https://www.pda-soft.de/mp2k_battery_pack.html)
>> on rebuilding a Newton 2000 battery pack.....Does anyone know what that
> 
> switch is?
>> Yours,
>> Christian
>> 
> 
> Dear Christian,
> Frank's website is a great resource when rebuilding.
> 
> I took apart the Rechargeable Packs before and reused the parts to convert
> a Battery Tray  so I can use NiMH AA cells.
> Take a look at the photos I have here. (These are two sets of photos I took
> when I made revision 1 and 2)
> 
> https://www.flickr.com/photos/sonnyhung/albums/72057594074185913/with/107275162/
> https://www.flickr.com/photos/sonnyhung/albums/72057594079049821
> Set 2 I have a diagram at the end on how I did my conversions with
> simplified instructions.
> Similar to reverse engineering like the take apart of a Rechargeable Pack.
> 
> There are two important parts are a) Polycell Fuse and the b) Thermistor.
> I don;t know the specs as I'm not as technical as others here.
> Others should be able to chime in on this to give more technical specs.
> I hope this helps.
> 
> God bless,
> 
> Sonny Hung
> the Hung Family
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