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Subject: Mystery: Voltage for JBR V1 batteries

Mystery: Voltage for JBR V1 batteries

From: <>
Date: Wed, 19 Jul 2006 15:25:23 -0700 (PDT)

I have an Archos JBR V1 Recorder which I'm using as a car player. I am
using an DC/DC inverter rated at 2.2A output

that takes the car 12V and outputs 6V or 7.5V nominal. I put that
power into the battery terminals of the Archos. I am finding that the
Archos isn't working right:

1. When the inverter is set to 6V I measure about 5.3V actually going
into the Archos. It stays on the splash screen for a while and then
gives the message PANIC ATA -1.

2. When the inverter is set to 7.5V I measure about 5.7V actually going
into the Archos. It plays normally for a couple of seconds then the
screen goes all black.

3. When the inverter is set to 9V, the screen went all black
immediately, and stayed black when I use it with batteries which work

I also tried putting a 200mfd capacitor in parallel with the power
source to stabilize it in case the hard drive was using more power
momentarily, but that didn't help.

So all of this points to the car inverter just not putting out enough
power, except one thing: Before I did these experiments with the car
adapter I was able to run the Archos fine with a home "wall wart"
(rated 800mA) fed in through the battery terminals, at 6V. After doing
these experiments (#3 being the culprit I suspect), when I run the
Archos at 6V nominal with the wall wart it just goes to black screen,
and when I run it at 4.5V nominal, flickers alot and shuts down
quickly. So I suspect that I have messed up some of the power
circuitry somehow by trying to run it with too high of a voltage. But
it still runs fine on batteries charged outside. The charging circuit
on this unit was already broke.

To cut to the chase, what I'm wondering is:

- Does anyone have accurate specs on how much current the JBR V1
Recorder uses out of the battery terminals, max and/or continuous?

- Does anyone have any info on what voltage range is allowable on the
battery inputs?

- Any idea why the car inverter rated at 2.2A would fail to run the
Archos at 6V would fail to run it, while the home adapter rated at
800mA used to run it successfully? And why does it run right on AA
NiMH batteries but neither of these inverters works? Could it be that
the Archos needs "cleaner" power than the switching supply can deliver?

I got another JBR V1 to replace this one, and before I start
experimenting with it I want to make sure I'm not going to destroy it
the same way :-!

Received on 2006-07-20

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