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Does anyone know where to find a spare power supply or car power supply?The stock supply is a 12v switching supply, but the PDN battery is only 7.4v. Can you charge with a 8.4v or 9v charger?Also, the charging tip is unique. What is the size (I think it is 3.4mmx1.3mm)?
 

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I happened to have a spare 9v, 300mA AC adapter around (one of thoese cheapo where you can choose between 3v/4.5/6/7.5/9v) and I used it to charge my PDN half a dozen times. Nothing blows up (yet). It does charge -- taking much longer of course. Using the stock charge, I can charge from 0% to 100% in 4 hours or so; using the 9v adapter, it took about 4 hours to go from 0% to 70%, and then hours (6? 8? 10?) to get to 100%.I'm operating under the assumption that slow charge won't hurt. Wait, I can just see a queue forming outside my room waiting to throw rocks at me :)
 

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ppl are busy hacking their toy. Sure I'd love to find a compatible power adapter or 2-3, to put them in the Bed, in the Bathrooum, and certainly Beyond (the toilet, lol) eBay? Big Radio Shagg might have extensive choices, plus needed tips. Somebody needs to start.Last, but hardly the least, I wonder what does it take to replace the stock piss poor battery with something 3...4 times of its capacity.
 

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Discussion Starter · #6 ·
The original power supply is a 12v switching power supply. Does that mean I can't just use a 12v car adapter with the right tip to use and charge while in the car, as a passenger of course ;)
 

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The PDN power supply is 12V @ 1.5A (18W). It is printed on the supply. I believe the tip is a 2.5mm tip with center (+) and outside (-). Easy enough to find 12V wall-warts (Most Linksys (Cisco) routers uses a 12V supply with that rating) but the length of the tip is going to be hard to find. I dug around in my junk pile and noted that most charger tips are not as long as the PDN.
 

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probably. check wattage, etc. though.
 

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PPL;40432 said:
The PDN power supply is 12V @ 1.5A (18W). It is printed on the supply. I believe the tip is a 2.5mm tip with center (+) and outside (-). Easy enough to find 12V wall-warts (Most Linksys (Cisco) routers uses a 12V supply with that rating) but the length of the tip is going to be hard to find. I dug around in my junk pile and noted that most charger tips are not as long as the PDN.
Length is not important. It's designed to be used with the base, remember. Just don't use the base...
 

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They don't give horny hats and mod privileges to everyone...
 

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Rule of thumb about replacing AC adapters: Voltage should match exactly, tip size should match well enough to make reliable contact, current rating should be equal or greater than the original. This works for most normal barrel plug gadgets.The PDN regulates down that 12V to power a built in charger circuit. The charger probably requires 7.2v + some margin to be able to generate a charge current. 12V adapters are very commonly available at high currents, much moreso than 9V, so that's probably why they chose it. Consumer gadget makers are always looking at their bottom line, and they wouldn't think twice about burning a few watts in going from 12V to 7.5V or so versus using 9V to shave 25 cents off the bottom line.I bet it will work on 9V though. When dealing with gadgets that have to regulate the voltage downwards (switching buck or linear converters), you can't destroy something by going under the usual voltage.
 

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agreed, never over voltage, or amperage. lower amp charging (trickle charging) is supposed to increase battery length (mah) but takes longer to charge, depending on whether the cells are nicad, lithium ion, nimh, or poly lithium the charging cycles diff....ehh... just take it with you to radioshack
 

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[quote name='secretseven;40736]agreed' date=' never over voltage, or amperage. lower amp charging (trickle charging) is supposed to increase battery length (mah) but takes longer to charge, depending on whether the cells are nicad, lithium ion, nimh, or poly lithium the charging cycles diff....[/QUOTE']Half right. The voltage of an adapter is fixed (for the most part) but the amperage is a maximum rating. If the PDN's adapter is 12V at 1.5A, that means that it can supply up to 12*1.5=18W of power. It will give out 12V as long as the current stays under 1.5A. The charger built into the PDN is controlled by its own processor and regulates the current to the battery based on the battery temperature, discharge history, and how readily it's accepting the power it's providing. If it didn't, the battery would overheat and catch fire. So when it's charging a dead battery, it's probably drawing near 1.5A, and when it's keeping the battery topped off it's drawing a fraction of an amp.
 

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[quote name='pokey9000;40728]Rule of thumb about replacing AC adapters: Voltage should match exactly' date=' tip size should match well enough to make reliable contact, current rating should be equal or greater than the original. This works for most normal barrel plug gadgets.[/QUOTE'] I have measured a number of 12V DC power supplies. Most of them provide more then 13V, some as much as 18+V. Don't take the word of the adapter (what it says on the case). Be sure to check the voltage so that you don't hit the battery, voltage-wise, too hard -and reduce it's life considerably.I took a large (in size) 12V (really 12V) 1A adapter, and soldered a tip (the full wire, not just the tip) to the circuit board of the adapter. It is working GREAT. In fact, even though it is rated at only 1A, I believe it is charging my PDN faster then the adapter that came with the PDN (rated at more then 1A).I also have a really great adapter from Radio Shack (no wise cracks) that is multi-voltage, multi-tip. It is right on with the voltage and is capable of about 2A. I don't have a tip that will fit (I need to go in and try to find one), but I suspect it would even heat the battery up a little high, because it could draw more amps from the adapter than the battery should safely be drawing. That can reduce the life of the battery, too.
 

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Granted the cheap chargers output may be all over the place, but their output is often lower when connected to a load. DVM doesn't provide proper load. Good idea to check the output, 'cause you never know what you are getting in these little black boxes that the Chinese put together & slap a label on.
 

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Has anybody found a supplier for the Home (and / or Auto) back-up power supply? (aka: radio shack part# and tip#)I have tried to use my PDN for breaks at work and thought that I had powered down only to find that I had put into sleep mode which still uses power and afternoon break comes along and no power to read by...:David
 

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energizer makes a portable rechargeable battery that has an appropriate tip, as do igo and the other radioshack portable charger.
 

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[quote name='lawman;67229]energizer makes a portable rechargeable battery that has an appropriate tip' date=' as do igo and the other radioshack portable charger.[/QUOTE'] Could you list some part numbers? as I have been ''Banded'' from my local Radio Shack Store for knowing more than the store manager about sales and their products as I "".. cost them money by telling customer items are on sale per their web site"..The local store was only "selling'' items at the online+instore sale price if asked for the sale price,, if customer did not ask they did not get the sale price..:David
 
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