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Dave Owen
2005-02-03, 17:25
>sadly, this is a very tricky thing.

Thanks for chiming in, kdf. You're absolutely right that without knowing
the true power draw of the unit/power output curves of the battery, it's
still a crapshoot. But hey, that's why most people buy prepackaged
battery-powered mp3 players, right? The manufacturer has already taken
the research and development hit for battery life. Not that that's any
guarantee, either (I still have less than fond memories of my little
Psion handheld's battery life).

kdf
2005-02-03, 17:35
Quoting Dave Owen <dowen (AT) sapient (DOT) com>:

> >sadly, this is a very tricky thing.
>
> Thanks for chiming in, kdf. You're absolutely right that without knowing
> the true power draw of the unit/power output curves of the battery, it's
> still a crapshoot. But hey, that's why most people buy prepackaged
> battery-powered mp3 players, right? The manufacturer has already taken
> the research and development hit for battery life. Not that that's any
> guarantee, either (I still have less than fond memories of my little
> Psion handheld's battery life).

Indeed. My garage door opener died after only 1 month of -9C winter nights. The
previous set lasted since the beginning of the 2004 :)

I'm really curious to know how the squeezebox would handle the slowly lowering
battery voltage over the long term. Likely only Sean knows the answer to that
one...although Felix might have experience with that.

-kdf

Enno Davids
2005-02-03, 17:46
On Thu, Feb 03, 2005 at 04:35:33PM -0800, kdf wrote:
|Quoting Dave Owen <dowen (AT) sapient (DOT) com>:
|
|> >sadly, this is a very tricky thing.
|>
|> Thanks for chiming in, kdf. You're absolutely right that without knowing
|> the true power draw of the unit/power output curves of the battery, it's
|> still a crapshoot. But hey, that's why most people buy prepackaged
|> battery-powered mp3 players, right? The manufacturer has already taken
|> the research and development hit for battery life. Not that that's any
|> guarantee, either (I still have less than fond memories of my little
|> Psion handheld's battery life).
|
|Indeed. My garage door opener died after only 1 month of -9C winter nights. The
|previous set lasted since the beginning of the 2004 :)
|
|I'm really curious to know how the squeezebox would handle the slowly lowering
|battery voltage over the long term. Likely only Sean knows the answer to that
|one...although Felix might have experience with that.

In fact, just tying it directly to the battery is unlikely to be a good
idea. A better solution would be a Dc to DC converter which would also
provide some isolation from odd behaviour on the input DC side and
provide regulation and current limiting. The cheapest are likely to be
the ones made for automotive use and might in fact drive you to choose a
12V battery rather than hoping a 5v or 6v one produces the right sort
of power by accident.


E.

kdf
2005-02-03, 17:50
Quoting Enno Davids <enno.davids (AT) metva (DOT) com.au>:

> On Thu, Feb 03, 2005 at 04:35:33PM -0800, kdf wrote:
> |Quoting Dave Owen <dowen (AT) sapient (DOT) com>:
> |
> |> >sadly, this is a very tricky thing.
> |>
> |> Thanks for chiming in, kdf. You're absolutely right that without knowing
> |> the true power draw of the unit/power output curves of the battery, it's
> |> still a crapshoot. But hey, that's why most people buy prepackaged
> |> battery-powered mp3 players, right? The manufacturer has already taken
> |> the research and development hit for battery life. Not that that's any
> |> guarantee, either (I still have less than fond memories of my little
> |> Psion handheld's battery life).
> |
> |Indeed. My garage door opener died after only 1 month of -9C winter nights.
> The
> |previous set lasted since the beginning of the 2004 :)
> |
> |I'm really curious to know how the squeezebox would handle the slowly
> lowering
> |battery voltage over the long term. Likely only Sean knows the answer to
> that
> |one...although Felix might have experience with that.
>
> In fact, just tying it directly to the battery is unlikely to be a good
> idea. A better solution would be a Dc to DC converter which would also
> provide some isolation from odd behaviour on the input DC side and
> provide regulation and current limiting. The cheapest are likely to be
> the ones made for automotive use and might in fact drive you to choose a
> 12V battery rather than hoping a 5v or 6v one produces the right sort
> of power by accident.

oh sure...but what's the fun in that? ;)
-kdf

momerath
2005-02-03, 18:54
Thanks guys!

That is what I was afraid of. I'm glad I didnt buy both items
thinking I could just stick em together. I've been writing code since
I was six, but I'm only just getting into hardware and coming to grips
with the basic (and basically weird) properties of analog circuits. I
have some friends who can surely get this working for me, but I want
to do it myself this time (and I will document it). Thanks for the
tips!

Do you think an email to sales or tech support would reach anyone not
reading this list? I'd love to know more specifics about the power
requirements, and I'm wondering if it might still be possible to buy
one with the older display. Are there any downsides to that setup
apart from the limited resolution? It would be nice to have a pretty
display in my bedroom, but I couldn't care less on the bus or at the
office, as my ipaq and workstation will be readily available with the
web interface (which I anticipate will be the starting point for my
hacking).

~Michael


On Thu, 03 Feb 2005 16:50:04 -0800, kdf <slim-mail (AT) deane-freeman (DOT) com> wrote:
> Quoting Enno Davids <enno.davids (AT) metva (DOT) com.au>:
>
> > On Thu, Feb 03, 2005 at 04:35:33PM -0800, kdf wrote:
> > |Quoting Dave Owen <dowen (AT) sapient (DOT) com>:
> > |
> > |> >sadly, this is a very tricky thing.
> > |>
> > |> Thanks for chiming in, kdf. You're absolutely right that without knowing
> > |> the true power draw of the unit/power output curves of the battery, it's
> > |> still a crapshoot. But hey, that's why most people buy prepackaged
> > |> battery-powered mp3 players, right? The manufacturer has already taken
> > |> the research and development hit for battery life. Not that that's any
> > |> guarantee, either (I still have less than fond memories of my little
> > |> Psion handheld's battery life).
> > |
> > |Indeed. My garage door opener died after only 1 month of -9C winter nights.
> > The
> > |previous set lasted since the beginning of the 2004 :)
> > |
> > |I'm really curious to know how the squeezebox would handle the slowly
> > lowering
> > |battery voltage over the long term. Likely only Sean knows the answer to
> > that
> > |one...although Felix might have experience with that.
> >
> > In fact, just tying it directly to the battery is unlikely to be a good
> > idea. A better solution would be a Dc to DC converter which would also
> > provide some isolation from odd behaviour on the input DC side and
> > provide regulation and current limiting. The cheapest are likely to be
> > the ones made for automotive use and might in fact drive you to choose a
> > 12V battery rather than hoping a 5v or 6v one produces the right sort
> > of power by accident.
>
> oh sure...but what's the fun in that? ;)
> -kdf
>

kdf
2005-02-03, 19:41
Quoting momerath <michael.warnock (AT) gmail (DOT) com>:


> Do you think an email to sales or tech support would reach anyone not
> reading this list? I'd love to know more specifics about the power
> requirements, and I'm wondering if it might still be possible to buy
> one with the older display. Are there any downsides to that setup
> apart from the limited resolution? It would be nice to have a pretty
> display in my bedroom, but I couldn't care less on the bus or at the
> office, as my ipaq and workstation will be readily available with the
> web interface (which I anticipate will be the starting point for my
> hacking).

Most of the staff at slim devices read and participate in this list. They have
been a bit silent of late, but there is a whole load of effort going into the
development of 6.0 so I'm not too surprised. An email to
support (AT) slimdevices (DOT) com certainly wont hurt. I would be surprised if they have
any of the old displays in their stock (they would have sold them off at a
discount a while back), but some of the distributors might not have rid
themselves completely, and Slim guys might be able to point you in the right
direction on that.

In general, however, a new one wont cost all that much less since the cost of
the new display really isn't that different. Downside is mostly readbility as
the old display only has a standard character set, and a faked double size
built from the limited custom characters available. The featureset is the same
for the core server stuff.

-kdf

Marc Sherman
2005-02-04, 07:51
momerath wrote:
>
> Do you think an email to sales or tech support would reach anyone not
> reading this list? I'd love to know more specifics about the power
> requirements, and I'm wondering if it might still be possible to buy
> one with the older display.

There's at least one SB with the old display available in Canada:
http://www.kawarthatv.com/computers.html
and search for "DEMO BLOWOUT".

- Marc

momerath
2005-02-04, 10:03
If I want a quick out-of-the-box solution to try, would I be better
off with a pack that is designed to drive multiple voltages including
5v or one made just for 5v. I'm guessing the switchable voltage means
the device has a dc-to-dc convertor and the voltage would be more
consistent as the battery dies. Am I missing something?

On Fri, 04 Feb 2005 09:51:12 -0500, Marc Sherman <msherman (AT) projectile (DOT) ca> wrote:
> momerath wrote:
> >
> > Do you think an email to sales or tech support would reach anyone not
> > reading this list? I'd love to know more specifics about the power
> > requirements, and I'm wondering if it might still be possible to buy
> > one with the older display.
>
> There's at least one SB with the old display available in Canada:
> http://www.kawarthatv.com/computers.html
> and search for "DEMO BLOWOUT".
>
> - Marc
>