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Re: HHB Portadisc

Subject: Re: HHB Portadisc
From: Walter Knapp <>
Date: Wed, 03 Sep 2003 17:49:51 -0400
Dominique Laloux wrote:
> Most of time, I keep the Portadisc in pause mode while on a site. The
> NiMH batteries (not the most expensive ones, though) will give me about
> hour of autonomy when fully charged... As I always have the second set
> with me, that gives me plenty of autonomy.
> 
> A weak point of the Portadisc is its "battery charge" meter, that I find
> to be less accurate than I would like. It will show the charge go from
> 95 to 75 very quickly, then it will stay at that level for a long while
> before going gradually down to about 30. The bottom of the scale
> (30..10..0) is again very fast. I experienced several times a automatic
> shutdown well before I expected it to happen. Now, I am a lot more
> careful. I suspect it is the meter, but, of course, it could also be the
> way the batteries are giving away their charge.

The metering is based on the discharge curve of alkaline batteries, 
who's voltage drops steadily throughout their life. In comparison NIMH 
batteries hold voltage through at least 80% of their entire charge. So, 
by the time you have the battery indication dropping, you are already 
through 80% of the NIMH charge.

I highly recommend you don't go below a indicated 70-80% on the 
Portadisc. To do so will shorten the life and capacity of your NIMH 
batteries.

Walt




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