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Subject: Re: Testers wanted: up to 50% greater battery life

Re: Testers wanted: up to 50% greater battery life

From: TP Diffenbach <>
Date: Tue, 29 Jul 2003 12:18:02 -0400

Quoting John Stevenson <>:

> I am interested but have a couple of questions for
> you.
> 1) How will we know the time it will switch off, I
> would intend to leave mine running overnight, since I
> use it on the train during the day (a two hours each
> way commute). I do not suppose you want us to sit and
> wait (the phrase a watched pan never boils springs to
> mind.) (Maybe add a setting that can time the number
> of hours unit is on, against battery capacity)

Once I get my PC's MBR fixed (and that will be a nightmare, I'm sure), I intend to add some battery monitoring to the build, which will write a file to disk containing the metrics. You'll just turn the unit on, load my build, and ignore the unit. When the test has finished (and you've charged up again!) you'll copy the test file to your pc and email it to me.

Of course, no personally identifying information will be collected; mp3-specific information will be limited to bit rate.

NOTE: for my testing, I've left the headphones attached (and did I ever look like a freak out at the bars friday, with the headphones over my shoulder, playing into my chest and shoulder blade, while I manually typed the voltage into my pda), as I'm sure that powering the headphones affects the voltage used. I'd prefer you do the same, and at a consistent volume level (90 is what I've been using so far).

I'd like, but do not insist, that you play CBR MP3s of a known bit rate; the monitoring software will attempt to figure this out regardless, but CBR will make graphing the metrics quite a easier. (I made a special 320 kpbs CBR rip of a 1924 production of "Princess Ida" which was transferred from 78 rpm records to CDs. At 320 kbops, I could hear every pop and crackle!)

> 2) I have two sets of batteries running in my JBR20,
> the orginal set (1500) and a 1700 set. Which I swop
> and change using a fast charger - will this make a
> difference? Or would you want test results for both
> sets?

I'd like the test to use one set of batteries at a time. If you're willing to do two tests, one of each set of batteries, that would be great. But swapping batteries during a test would throw off the metrics.
> 3) Will it be flash compatible, or will be need to
> ROLO to use it and will that effect the results?

It'll be an .ajz (or .mod). While it could be flashed, I see no point to doing so, as it will be a) beta and b) not maximally efficxient, given the monitoring overhead. So you'll have to rolo it to start the test.

> 4) Your testing would not be 'real life' based,
> people do not use their player in that way. Might be
> best to time over normal usage - more people could
> take part then. The normal stuff such as switching
> on, off, (which uses more battery power) creating
> queues and just playing with it, that way you will get
> a more realistic set of metrics.

I'd like to get a baseline, and then I planned to appeal to interested testers to give me a "normal use but continuously on" test and a "purely normal use" test.

Again, I'll cover exact procedures when I email testers the link to their testing copy.

Archos FM has a Rockbox!
Received on 2003-07-29

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