From: Andrew Jamieson <andrew.jamieson_at_projectlab.net>
Date: Tue, 29 Oct 2002 10:31:40 +1100

This should be no problem. Just make sure that the voltage does not go
above 5.5V (exactly 5V is ideal). To get the Archos to run for a week,
you'll need a ~ 100mA X (7 X 24) = 16.8Ahr , assuming 100mA average when
operating, and a 100% efficient voltage regulator on your battery. A car
battery with a linear 5V reg (such as a 7805) should be ample; just watch
that the reg doesn't get too hot.


Andrew Jamieson
----- Original Message -----
From: "Dave Jones" <dave_at_hfpacoustical.com>
To: <rockbox_at_cool.haxx.se>
Sent: Tuesday, October 29, 2002 7:14 AM
Subject: Large External Battery for Ultra-long Play


> First of all, I love the Rockbox firmware. It's very cool what you all
have
> done.
>
> I have a question that is a little outside the scope of firmware, but is a
> pressing one for me.
>
> I'd like to be able to run my Archos recorder for a very long time, i.e. a
> week or so, without charging it or attending to it at all. I'd like it to
> run continuously during this week. It will be in a location without access
> to external power.
>
> I've tried connecting an external battery pack through the dc power plug
> but I seem to get strange behavior. When the recorder starts using the
> external power for charging the internal battery, the recorder hangs,
> requires a button press, etc. (I'm still using the Archos crappy firmware
> because I'm using the recording functionality.)
>
> Anyway, does anyone see any problem with building an external power source
> with voltage regulation etc. such that I could tap directly into the
> internal battery contacts on the Recorder? With a large battery pack I
> should be able to power the recorder for a week without much difficulty. I
> should be able to pop the Recorder open (using the very handy instructions
> on the Rockbox website) and tap directly into the power leads, right? As
> long as I am careful about the quality of the power feed?
>
>
> Thanks for any comments,
>
>
>
> Dave
>
>
>
>
>
> _______________________
> Dave Jones, Senior Project Consultant
> HFP Acoustical Consultants Inc.
> 6001 Savoy Dr., Suite 115
> Houston, Texas 77036
> 713.789.9400 (phone)
> 713.789.5493 (fax)
> www.hfpacoustical.com
> _______________________
>
>
Received on 2002-10-29