Hi Greg-- Sounds like a fun trip. The ECO's are great and it seems
like they came down in cost quite a bit since I last looked. If you
have the money and/or no interest in soldering their, 12 volt EC-90
battery/charger has about 75% of the capacity for about the same
first unit price. You come out ahead with the DIY packs if you need
additional packs which are about half the cost. (Although ECO
mentions selling the powerpacks separately too I see,..) I like that
the MAHA charger can charge the other batteries I need too. It
charges very quickly, keeps track of the charge total and goes into
trickle rate. It can test a battery and re-condition a single cell or
a whole battery pack. With the seprate charger design, I can charge a
dead pack at camp on popweing the MAHA in a car battery. The DIY
packs weigh about 1lb less but its a lot less pretty.
The 722 does use some juice but these packs have considerable
capacity, about as large as one can go. (Though the RC hobby folks
always have new, hi capactity, low weight/bulk, batteries they are
trying out it seems). A charged pack will hold a charge for easily a
couple of weeks. Here's a page with more info:
http://www.uwm.edu/~type/Mic%20Preamps/BatteryPack_NiMH_722/Battery10KaHr_7=
22_744.htm
Rob D.
=3D =3D =3D =3D
At 9:00 PM -0500 9/5/05, Gregory Rademacher wrote:
>Rob,
>If I spend a week in the Ontario bush how many packs like this might
>I need for
>normal .. non continuous recording on a 722. How long will they hold
>a charge if unused?
>I was wondering , because I have some new NiMH AA's for a PCM 1 and
>they don't seem to hold a charge for a long period of time when I'm
>traveling. The 722 goes through batteries relatively quickly it seems.
>I was thinking of constructing a battery belt similar to a video
>camera or light source for an extended stay or buying a couple of the
>Eco-charge batteries.
>Any thoughts?
>
>Greg Rademacher
>
>
>On Sep 5, 2005, at 11:27 AM, Rob Danielson wrote:
>
>> Sorry, didn't mean to send battery pack info yet. Tried to juggle to
>> many things at once.
>> You'll need a minimum of 10 cells, here's the info, complete this
>> time:
>>
>> =3D =3D =3D =3D
>>
>> Costs is ~$190 for a very nice 12 volt battery pack with charger and
>> requires soldering skills.
>>
>> 1) 10 high capacity (10,000 mAh) D size NiMH, rechargeable cells
>> 1- 8 pack http://www.batteryspace.com/index.asp?
>> PageAction=3DVIEWPROD&ProdID=3D711
>> 2 -singles http://www.batteryspace.com/index.asp?
>> PageAction=3DVIEWPROD&ProdID=3D709
>> ~$65 total
>>
>> I've been using these cells in 3 battery packs for over a year with
>> the 722 and 744 and I've never one down as I rarely record for over
>> 24 hours straight.
>>
>> 2) You can mount the D cells in 3 of the 4-slot plastic battery sleds
>> from Radio Shack or on line surplus electronics supplier and strap
>> them together with good tape and slip them in the cardboard box the
>> batteries came in.
>>
>>
>> 3) Connector, Soldering & Cabling:
>> To connect with the 722/744, you'll need a 4 pin HiRose Connector:
>> #HR10-7P-4P Digikey part# HR100-ND "Insert "HR100-ND" here:
>> http://www.digikey.com/ I think they have a $25 charge minimum, so I
>> bought some extra.
>>
>> Pin 1 =3D negative ; Pin 4 =3D + (10-18 volts; I'm running 12 volts wi=
th
>> above pack. You could use their smaller C size and still get many
>> hours. The 722/744 will run on more voltage, but I've found the MAHA
>> charger below is not as happy charging packs larger than 12 volts. I
>> also charge in my car and the MAHA does not support larger voltage
>> packs powered by 12VDC..
>>
>> I use high quality, rubber mic cable that's 3/16" diameter so the
>> HiRose connector can get a good grip and provide excellent strain
>> relief. The weight of the 722/744 can end up resting on this
>> plug/cable, so care here is advised.
>>
>> The pins are tiny so take your time. Once, I goofed and wired the
>> polarity backwards, but SD added idiot protection. The decks ignores
> > the pack if the polarity is wrong.
>>
>> 4) High Capacity NiMHBattery packs are tricky to charge. I've played
>> with three DIY designs and after having modest success, I spent $95
>> on a MH-C777Plus-II charger.
>> http://www.mahaenergy.com/store/viewItem.asp?idProduct=3D185 It can
>> charge anything be it nicad, nimh, or lion-- very quickly and
>> reliably. It will recondition old battery _packs_. This feature alone
>> got me my $ back.
>>
>> It takes about 8 hours to charge on the the 10000mAH pack.
>>
>> Again, sorry about the incomplete first post! Rob D.
>>
>>
>>
>>
>> --
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
>> "Microphones are not ears,
>> Loudspeakers are not birds,
>> A listening room is not nature."
>> Klas Strandberg
>>
>>
>>
>> SPONSORED LINKS
>> Science kits Science education Science kit for kid
>> Natural sound Recording technique My first science kit
>>
>> YAHOO! GROUPS LINKS
>>
>> Visit your group "naturerecordists" on the web.
>>
>> To unsubscribe from this group, send an email to:
>>
>>
>> Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
>>
>>
>
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--
Rob Danielson
Film Department
University of Wisconsin-Milwaukee
[Non-text portions of this message have been removed]
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