Re: [NTLK] 2100 power supply

From: Woody Smith <>
Date: Sat Oct 25 2008 - 20:10:03 EDT

Whether or not you charger is safe depends on whether it is regulated.

Your charge pattern does not seem particularly different from mine and
I uses a Newton 9 W adapter with a re-celled pack 2500 mAh cells.
NiMH cells are rated at 1.2 volts so I would expect that four in
series would be 4.8 but I usually get a reading of something over 5
with a meter and about 5.6 with Avi's backdrop.
Why do you think it isn't a full charge?
If you aren't getting the life you expect it may take a few charge
cycles to get maximum life or you may have a problem with your
soldering. A weak solder joint can introduce resistance and lead to
shorter life, as can an overheated battery.
But your readings are consistent with a good pack.


On Oct 25, 2008, at 4:11 PM, Stephen Davies wrote:

> Hi,
> I recelled my 2100 battery pack - thanks to the excellent
> instructions at
> Pretty sure I did it right - and my Newton seems
> convinced.
> But I don't have a proper Newton power supply. I have a beefy
> supply giving
> about 6.5v output with no load. I've read all the warnings about
> wiping out
> my Newton but that is a safe voltage and it powers my Newton fine.
> But this supply doesn't seem to be able to fast-charge my newly
> recelled
> pack properly. When I first plug it in then my Newton shows
> fastcharging
> and a charge current of around an amp. That drops the supply
> voltage to
> about 6v. The battery voltage gradually climbs and when it gets to
> about
> 5.6v it switches to trickle charge. The slip claims that the
> batteries are
> charged. But the cells are definitely not properly charged.
> I guess that my supply voltage is too low? I know that I really
> need a
> voltage regulated and current-limited supply, but I'm not sure where
> to get
> such a thing and what the next-best would be?
> Thanks,
> Steve

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Received on Sat Oct 25 20:10:09 2008

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