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Post by Tulio Adriano on Feb 9, 2006 11:15:53 GMT -5
Tomman, I read your post and it sounds much more like a project you want to do for hobby than for the need of a cheap discman, since you spend 60 dollars to buy a generic brand discman and you'll spend 50 dollars with a 8 battery pack without charger, plus the charger it will surpass the 60 dollars discman price... Anyway I like your project! I do not understand anything about eletronics but I had a experience with using nonstandard batteries to power up devices. Back in 1999 the digital cameras was better known as "battery suckers" since the LCD displays at that time consumed so much power that alkaline batteries would last less in a digital camera than in a GameGear unit. For that problem my fried adapted a motorcycle battery to the camera and it could last more than 1 month of intensive use. He used a beltbag to carry the battery and the cord was plugged in the DC In of the digital camera. You can try that, for motorcycle batteries are much smaller than car batteries making them able to be carried easily. Well, that's it. Good luck!!! i know brazil has their own MTV =P Yeah... I remember it back in 1994 but I really don't know since when it does exist here. Cya Tulio
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Post by Tom Maneiro on Feb 9, 2006 19:03:44 GMT -5
Use a motorcycle battery... it seems too big to fit in my backpack (add a CD drive, two notebooks, a 1350-page Leithold calculus, a calculator... and you got R-RIP!)
Howevr, i found some small but hi-powered batteries for electronic devices such fire detectors and 24-hour-on devices. these are about $20, so these are affordable. The basic plan includes a $10 AA battery bank, and since it would last for no more than 3 discs (if i'm lucky, i need batteries to test)... it could be a nice idea.
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oompa loompa
I AM THE GOVERNATOR
"Git 'Er Dun!"
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Post by oompa loompa on Feb 10, 2006 1:32:02 GMT -5
oh =P, now we're aiming for compactness =D
good news for you, like i said before, for example: the drive won't always draw like 1.5 Amps of 12 volt power, even if the device specifies that it requires 1.5 amps of +12v. for instance, when you're using the cd player for playing a game on a computer, and the game is loading stuff from the cd, you'd expect the cd player to be running at like 52x (or whatever the fastest the motor spins at). spinning the cd at the maximum speed of the motor draws some heavy amprage. when you play a music cd, the cd doesn't even spin fast at all. you can barely hear the cd player spinning your disc when playing music cd's sometimes =P
that's why it's best to check how much amprage the cd player draws when playing a music cd. just use a digital multimeter from a radio shack or something. you'll find that the cd player proably only draws 500 mA at +12v just spinning a music cd and powering the laser
i don't think those batteries will last very long in high current draw applications =P. their primary applications are low power consumption applications. drawing more amprage decreases the battery's life even faster
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Post by GiGaBiTe on Feb 10, 2006 4:29:37 GMT -5
the cdrom drive shouldnt draw the full voltage only playing audio cds, because if you notice when the computer plays and audio cd, it doesnt spin up to the max. now the 5v is probably less flexible with amperage, as thats all of the electronics stuff.
just go find some OLD 1x or 2x cdrom drives, those old behemoths should draw way less power since they dont spin nearly as fast.
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Post by Tom Maneiro on Feb 10, 2006 11:44:23 GMT -5
As i pointed in a earlier post, CD spins even with 9V, but drive starts to behave erratically. I got the CD playing 1 out of 20 times, and even if i change the track, playback dies and i must unplug the drive to retry.
The batteries that i've seen can output up to 3A, but these are not easy to found there. Better stick with AAs... After checking Duracell and Energizer datasheets, a single AA Duracell Ultra will be drained in 1 hour with a 1A load! Energizer datasheets put also some practic cases: a 250mA CD player will eat the batteries in more than 6 hours. How fast will my Cyberdrive player drain my 8AA batteries?
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oompa loompa
I AM THE GOVERNATOR
"Git 'Er Dun!"
Posts: 1,301
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Post by oompa loompa on Feb 10, 2006 11:48:43 GMT -5
i dunno how long it will take to eat up your AA's. if you look at the datasheet, you'll see a CUTOFF voltage. the CUTOFF voltage is the voltage in which your device stops to operate at.
just get like 12 AA's, and then plug it all up, and do a test =P
try seeing if you can get laptop batteries as well, since these are designed for high draw
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Post by Tom Maneiro on Mar 28, 2006 11:28:44 GMT -5
Finally i purchased the damn AAs, 8 Energizer model E91 ($6.85 for 8 batteries!!! Energizer's are damn expensive here, so i had to negotiate), so i started to build the final thing.
I tried to build a small battery holder with some old phonecards, a bit of foil and some tape, but it failed... Finally i stacked my batteries in two rows of four, taped securely to make contact, used a piece of foil to join both rows, and finally a custom power cable (a 4-pin header salvaged from a fuxored floppy drive and some cables) to deliver the power to the drive (and the 78M05). Now my CD drive is powered by a juicy 2850mAh battery pack. It works fine, it does not jam, and it still sucks because it hates burned CDs...
Once i get a camera, i will publish some photos here. I only want that these damn batteries lasts for more than 3 hours (BTW, Energizer updated their datasheets, now they point that their batteries are good for everything EXCEPT digital cameras, it sucks a entire pack in less than 1 hour!). Now it's time to save my cents to buy some rechargeables.
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Post by Tom Maneiro on Mar 29, 2006 15:27:22 GMT -5
In less than 30 minutes, the voltage of the battery pack was not enough to play a single disc: the disc spins, the LED flashes by a while, but the disc is no longer recognized ever by the drive. However, when i plug the drive to a PSU, it works fine. Damn Energizers! i expected 3 discs, but got only 6 or 7 songs... And the rechargeables are very far from my pocket
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Post by GiGaBiTe on Mar 29, 2006 16:26:13 GMT -5
you could try one of those 12 volt batterys used in alarm systems, although they are very heavy, they spit out around 13-15 volts and last a darned good while.
they are strong enough where one of them can power my computer for around 15 minutes if the monitor isnt on. and it draws alot of power too (dual PIII 1 GHz)
You can also recharge them (and you would probably want to as they are rather expensive.)
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Post by Tom Maneiro on Apr 27, 2006 14:11:02 GMT -5
(edited: Thanks!)
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Post by Tom Maneiro on May 27, 2006 23:15:38 GMT -5
Anyone knows a cheapo place to buy cheap replacement belts? I got more and more dead drives that can revived with a new belt, but i can't find these for cheap. I must recycle them from damaged drives...
A weird thing: a worn belt from one drive is the perfect replacement for another. Here is a simple chart:
-A worn belt from a dead Cyberdrive 482D fits nicely on a 240D -Samsung SC-152E's belts are perfect replacements for almost any drive. Don't worry if you overstretch them, as long as the belts have no cracks, your drive will be fine -Now i have another SC-152E with a worn belt and my only replacement is another worn... from a 240D (a LONG belt, unlike from the SC, it's quite short).
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oompa loompa
I AM THE GOVERNATOR
"Git 'Er Dun!"
Posts: 1,301
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Post by oompa loompa on Jun 2, 2006 15:21:44 GMT -5
get belts at like a local hobby shop
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Post by Tom Maneiro on Jun 3, 2006 20:13:19 GMT -5
I found a nice way to fix loose belts: spray them with paint, and powder it a bit with flour or something. This worked with my SC-152E...
Yes, i'm original because i'm lazy to walk to the nearest electronics store (in a damn hot highway, living near the equator it's a sentence of death if you want to walk freely on streets)
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Post by Tom Maneiro on Sept 7, 2006 23:02:55 GMT -5
This project is not dead... and i've done some research:
-There are some sealed "dry" batteries, thet can spit up to 12Ah! However, these are DAMN expensive ($50+) and DAMN heavy! (at least 2 pounds or 1 kilogram). -Belts are pretty cheap (less than 20 cents) -Rechargeable AAs are getting more and more expensive (i can buy 8 normal alkaline AAs for the price of a SINGLE 2150mAh rechargeable AA) -The next experiment will be with C-sized cells, but first, some fundraising...
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oompa loompa
I AM THE GOVERNATOR
"Git 'Er Dun!"
Posts: 1,301
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Post by oompa loompa on Sept 23, 2006 1:01:25 GMT -5
i think we should raise a fundraising for tomman to get himself an actual portable cd player that runs off of two AA batteries
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