cms

dont forget to mount a usb hub (5 bucks) that way you can attach multiple devices (you could probably charge 2 Palm TXs with it and still have some power to share from the batteries)

Nice to know that you can do that. I would but I needed something "low profile, that doesnt make too big of a statement"

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I have bought an Asus EEE 1000he. My palm TX is no longer needed. See my Replacer
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cms

both batteries are at 1v, and output is at 5.2v, but I realized that the blue light on the charger stopped blinking (I don't know when it stopped) so I guess the charger is telling me that It cant supply enough amperage from the dead batteries.

Im off to buy AA batteries

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I have bought an Asus EEE 1000he. My palm TX is no longer needed. See my Replacer
You can now find me on the EEEuser.com forums :)

ftwitty

What I posted was using FOUR (4) lithum AA batteries; there is not voltage boosting circuit. Mt Tx is getting 6 volts or so directly.

p.s. I wired my own using a (4) AA cell battery box with a Tx (or Treo) power connector I cut off an extra Treo charger. I've also used a commercial (4) AA cell battery box with standard USB connector along with a USB / Tx connector. Both work real nicely with lithum batteries.

I love my mom

If the AA's were still at 1v, that means it can provide charge for a good while longer at whatever amperage the charger requires.

With batteries, amps is rarely a problem. It's all dependent on voltage.

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ftwitty

Stopped by Target this afternoon. They were out of both teh USB and Treo versions...... I noticed that the other models came with lithum batteries.

cms

I hope you get better luck next time ftwitty

Have you tried ordering online?

__________________
I have bought an Asus EEE 1000he. My palm TX is no longer needed. See my Replacer
You can now find me on the EEEuser.com forums :)

cms

then why did the battery level of the palm drop to 27%?

I think this is one of those rare cases...

__________________
I have bought an Asus EEE 1000he. My palm TX is no longer needed. See my Replacer
You can now find me on the EEEuser.com forums :)

I love my mom

I've been wondering how you're getting 5.2 volts out of two AA batteries. It would make sense that the battery pack was simply to keep the device alive while you use it, but to charge it with 2 AAs is wierd. That only equals 2.4 volts, and that cant charge a 3.7 volt battery until the battery is drained below 2.4 volts.

I'm sure you realize this

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ftwitty

Thanks. I'll figure out something......

ftwitty

Yes, the charger charges a Tx when it is off.
The Tx charger produces 5 volts. Aparrently, the Eveready AA Tx charger must also produce 5 volts in order to charge the Tx. I guess the best way to think of it is as a "voltage pump". 3 volts is pumped up to 5 volts

Gregte

This explains the problem. You cannot measure the output of the battery pack/charger open circuit. This will not tell you what it is putting out under load.

If you are not willing to splice into your battery pack/charger or to remove the back cover from the TX in order to access the power input pins then there is no way you can know what the charger's voltage is under load. It probably is 5.2 volts with fresh AA cells but it cannot be even 5 volts if the TX's internal battery is dropping below 100%.

Gregte

If there is an amperage deficiency then there is a voltage deficiency. This is a simple law of physics with regard to electricity.

In other words, if you are supplying the voltage that a load wants then it will use a specific amount of current (amperage). It well only use what it wants.

If your power supply cannot supply the amount of current (amps) that the load wants then the supply's voltage will drop, thus showing the 'voltage deficiency'. If the supply's voltage does not drop then it is indeed supplying all of the current the device (load) is asking for.

This is why you cannot get a true reading of your power pack's output voltage if it is not connected to your TX.

itrush07

Nice one, I'm out for some hunting now.

Gregte

A way to measure the output of your battery pack without taking it apart or removing the back off the TX would be to provide a load other than the TX which will allow you to connect your multimeter leads to it.

The TX draws about 245 mili amps from its internal battery when it is ON, no apps running, and at full brightness. 245 mili amps at 3.7 volts is 0.9 watts of power. You would need to draw 181 mili amps at 5.0 volts from your battery pack to consume the same 0.9 watts of power.

Since E/I=R you could simply connect a 27.6 ohm resistor across the output of your battery pack and measure the voltage across that resistor. This will give you the actual voltage that your battery pack is putting out when connected to the TX if the TX's internal battery is fully charged and if your TX is ON with the screen at full brightness. There are some other small losses involved in reality but this will get you fairly close to the true voltage output of your battery pack.

Your battery pack probably puts out a true 5 or 5.2 volts with fresh AA cells, under load (connected to the TX). However, it cannot be putting out that much voltage connected to the TX if the TX is not able to maintain 100% charge status. If it were truly maintaining 5 volts under load then it would be providing all the current the load wants and so the load (the TX) would not be depleting its own internal battery.