Mmmmm.
I hope there is just a way to, you know, make it and use it without spending more than it's worth. Like, buying 40$ worth of accessories just to build it when you could get 2 extra battteries is a little much. I like the original idea, just maybe add some safety precautions on it. (Different battery, power regulator or something.....)
Paul123, i think you need to considder this a little moer deeply.
Think about what they're doing (which i am gonna try :D)
A car charger takes 12v (usually more like 15) and is designed to down it to 5.4v.
We are providing it with 9v. I'm fairly sure it can handle 9v when its made to handle 12.
Also, wired in parallel, they're only getting 9v, just more Mah, so more running time. u could put 50 there, the charger may not like it, but it will be the one that burns out, not the axim, as it will always do its job until it dies. stepping voltage down to 5.4v. or at least thats how i understand it.
Now i have a question. Do you have to destroy the nice car adaptor? because, if you dont, its designed for 5.4v, therfore you ALSO have an AXIM car charger! why not open the charger up, attach the wires, drill a hole in the casing, and seal it up again.
Anyway. This thing is BIG! the axim community has been looking for this for a LONG TIME. there are many many people here that are professionals in some way when it comes to electrics. all we have to do is wait for one and see what they say for certain.
ps. dont try one battery, u'll damage the axim from undervoltage. a 9v bettery, unrestricted, attached to a USB cable, cant power my USB speakers (not enough amps) but 3 AA's in series can.
with more than 1 9v though, it has more power\sources to draw from, so will be fine.
this IS cool. and, think about it, if you dont like the mod, just put the charger back together and voila, u have an AXIM car charger! (dont you)?
plz, someone pro provide input. Let us know if anything is wrong here, or if we've found the holy grail.
You mentioned that 1 battery would be bad because of insufficent power. What about when all 3 of your batteries are almost drained? Would it still be able to get enough power? Could that potentially damage things? (I have very limited knowledge of electronics, so I have no idea)
Originally Posted by Master_Scythe
ps. dont try one battery, u'll damage the axim from undervoltage. a 9v bettery, unrestricted, attached to a USB cable, cant power my USB speakers (not enough amps) but 3 AA's in series can.
with more than 1 9v though, it has more power\sources to draw from, so will be fine.
this IS cool. and, think about it, if you dont like the mod, just put the charger back together and voila, u have an AXIM car charger! (dont you)?
plz, someone pro provide input. Let us know if anything is wrong here, or if we've found the holy grail.
Well i assume with more than one 9v, providing more draw, they wont give out till they're almost drained. The X50v has a circuit to protect it from undervoltages. Just make sure u have SOME battery left when using it i'd say. the risk of damage i think would only be data loss.
STILL REALLY WANT AN ECECTRITION ON THE SCENE TO LOOK AT THIS!
9V batteries are not ideal for this application, because they are expensive and do not have much juice. You'd be better off powering the converter from a bank of 10 AA rechargeable batteries as someone suggested. This is slightly better than the direct 4 AA battery connection approach because the converter will allow the battery capacity to be fully utilised. However, you also have to remember that the step-down voltage converter is not 100% efficient. It'll probably have an efficiency of around 70%-80%, which is why it will get hot after a while. Also, there is the risk, however small, that something will go wrong with the circuit and it dumps the full 12V input into the axim and thereby destroying it. To prevent this from happening, a 6.2V zener diode should be used at the output to clamp the maximum voltage. In the event of an over-voltage, the zener will conduct, acting as a short circuit and blow the fuse instead of the axim.
I am just playing with two home made re-chargers, one only suitable for charging the X50V when it is off, the other for charging and running.
The charge when off version uses 5x AA batteries and suto turns off when the X50V is about 97% charged or if the batteries go flat. This version uses either NiMh or Alkaline. I am happiest with this version but need to refine it a little.
The run and charge version is the simplest and neatest but can only use NiMh batteries, it cost about $4. The problem with this version is the need to keep an eye on the way it is charging as currently it has no low battery detection.
mphayvanh, did you ever have problems witht the ORIGINAL battery charger?
No--still going strong for my PDA. The last test went strong at 5+ hours before I shut it off myself! I haven't had the emgergency since or the need to use it yet.
Commercially, the 1 battery 9v charger from eXpansys looks great. Using a rechargeable 9v is even better if you're afraid of overcharges.
I don't like to ask anyone to take risks on their PDA. This home made solution works for me (2 9v this time), but I want people to evaluate it for themselves or improve upon it for their own design. This is a cheap solution, but you also get what you pay for and the risk could be too great for some people.
After reading a few posts on poor battery life, I decided to make my own flicker free emergency battery--all weighing only 9.8 oz. If I had to guess, I think it'll last 2-3 days of non-stop use.
All you need is:
1. A Pelican PSP car charge (same voltage as the Axim charger and cheap)
2. Some battery holders (Radioshack or Fry's $3.00)
3. Axim adapter that came with the cradle
4. (3) 9 volt batteries
5. A case (a spare digital camera case will do)
6. Some soldering know-how would be helpful.
LET'S GET TO IT!
1. Crack open the car charger to expose the red and blue wires.
2. Solder the battery holder wires to the charger.
3. Use electrical tape or heat shrink to cover the solder wires.
4. Insert everything into the case.
It's pretty simple. :approve: You can do it just from the pictures. Now I don't have to worry about battery life while watching a movie or playing a game!
PS- You can buy a similar product online, but it only comes with 4 AA batteries plus the flickering--besides, what's the fun in that?! Make your own!
Disclaimer: ALWAYS USE CAUTION WHEN SOLDERING. IMPROPER WIRING CAN CAUSE SMALL EXPLOSIONS OR WORST, DAMAGE YOUR AXIM TOO!
Why did you choose 9 volt batteries, and why 3?
I am very tempted to make something like this. Not because I have experienced the need yet, but because I want to!
I have small solar element as power source, and a 5.4v converter. The solar came with 2004-2005 Audi cabrios as a memory backup during shipping from Germany to California. It works perfect, the solar also keeps my portable cooler alive for beach or pool times...
usa511
Last edited by usa511; 08-30-05 at 01:56 AM.
Reason: spelling
I am very tempted to make something like this. Not because I have experienced the need yet, but because I want to!
I bought something similar with 4 AA batteries and it flickered too much for my taste and someone else mentioned 8 AA batteries but it would be too cumbersome & heavy. 9 volts seem like the perfect size and voltage for the 12 volt input capacity charger. I tried 2 in parallel and found that it was too light. Three fit just right. There's no science really. Plus, the 9 volts comes in rechargeables now so it seem right to use them.
I have found that a battery holder for 4x AA works great for powering/charging the X50V. No voltage regulators required as long as you use Ni-MH batteries ONLY. You can get these battery holders cheap at places like Maplin 60p ish, for mine I made a short lead to a USB socket so I can use it for my Ipaq or other USB charged devices as well.
Not worked out a running time yet with 2100mAh AA batteries but if you are using this system to watch a movie for instance you will know straight away when the batteries are discharged because of the screen flicker.
Follow Us
RSS Feed
Follow on Twitter
Facebook
YouTube
