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Sike
2007-05-22, 11:39
Hi Everyone

I have been searching the forums for battery pack experiences. I have 10 Squeezeboxes throughout the house and my weekday/working-appartment. Now that summer is coming I would like to have a set-up for outside. I have been doing this the past summers using a portable sound system and a Squeezebox drawing mains power though a very long power cord.

I have bought myself the Apple-hifi (which can be battery powered) and would like to to put a (white!) Squeezebox on top of it. The aim is to get the Squeezebox running on batteries. From what I have read the SB needs 5v and 1000mw. The older topics on this state that you will only get an hour or so play from batteries. Nowerdays with NIMH batteries with up to 10'000mah this shouldn't be a problem:

http://www.ansmann.de/cms/consumroot/batteries/rechargeable/nimh-batteries/mono-d.html

or something like this:

http://www.bixnet.com/hicamiexbapa.html

Has anyone had any experience with this kind of thing?

My main questions are:
-A regular AA AAA C or D cell battery gives me 1.2v of power. the Squeeze needs 5. Will the 0.2v missing matter?
-Has anyone had any experience with this kind of thing?

Thanks

Sike

seanadams
2007-05-22, 12:15
It needs to be regulated down from a higher voltage. Something like this might work:

http://www.semsons.com/delaxpluginc.html

And if you want really long run time from a small battery, and you don't want to deal with wiring up a bunch of 1.2V cells, you may want to look into Lithium Polymer. However they're not cheap and you need a special charger:

http://www2.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=lipo&FVPROFIL=++&search3=Go

eg this one is only 8 oz and will give you about 12 hr run time

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXRVT8&P=7

SB3 draws 4.5W and a good chunk of that is the VFD. It is just not intended to run on battery power, but it can be done with a beefy battery.

You might also look into cordless power tool batteries as you get a lot of WH per $.

pfarrell
2007-05-22, 12:22
seanadams wrote:
> http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXRVT8&P=7

Wow, that is sure not cheap.
If you don't plan on moving it, just use a 12V motorcycle battery
and any trickle charger. It will have more than enough power to
run a long time.

Of course, lead acid batteries make a mess if spilled.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

AubreyCTurnerJr
2007-05-22, 14:33
Your problem isn't too different from what amateur radio operators face in trying to come up with power for emergency operations. Many hams use Sealed Lead Acid batteries (AKA "gel cells") because they provide plenty of power and they don't spill.

Here's a fairly inexpensive one that provides 5AH:
http://www.allelectronics.com/cgi-bin/item/GC-125/160400/12_VOLT_5_AH_GEL_CEL_BATTERY_.html

You could combine it with the 5V regulator linked above to get the voltage that the SB3 needs.

Then, all you need is a charger:
http://www.allelectronics.com/cgi-bin/item/BC-212/965/12VDC_500MA_2-STAGE_CHARGER_FOR_LEAD-ACID_BATTERIES_.html