Compaq iPAQ USB Cradle Charger Modification [Archive]

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Jason Dunn

02-08-2002, 08:14 AM

<a href="http://ecece.com/info/ipaqcradlemod/ipaqcradlemod.html">http://ecece.com/info/ipaqcradlemod/ipaqcradlemod.html</a><br /><br />By popular request, here's the very cool iPAQ cradle mod by Charlie Reverte.<br /><br />"Have you ever wondered why your stock iPAQ cradle doesn't charge your iPAQ using power from the USB port like every other aftermarket sync cable? Here's how you can modify (rice up) your cradle to do just that so you can use your AC adapter at work."

rene_canlas

02-08-2002, 08:28 AM

"Beat your kids"?
The guy who wrote this has poor taste when it comes to humor... :cry:

[Cruzer]

02-08-2002, 10:20 AM

Jason or anyone know how do this same mod on a 3800 cradle. I couldn't find any specs on the cradle to give it a try. The connectors are totally different. So anyone, anyone...

RC

Daniel

02-08-2002, 02:01 PM

I've done this mod on my H3660 cradle, it's a bit different, but it works. Very cool mod!

Daniel

ctitanic

02-08-2002, 02:06 PM

Basically, All you need is a voltimeter and check that you are getting 5 volts from your USB Cable, the red cable is positive. Then if you jump the red cable from the USB with the Red cable from your power plug you are all set. Check the picture a posted at my site showing both ways.

How to (http://www.pc-counselor.8m.com/How_to/how_to__pc_counselor.htm#usbcharger)

asatyss

02-08-2002, 02:51 PM

Thanks Jason! I am glad you were still able to find the article. I think I may try this soon, I will let everyone know how it went. :wink:

peterawest

02-08-2002, 03:00 PM

This is a nice option, but I hope you read the warning on his page:

"I think the reason Compaq made this cradle work off of AC power and not off of USB power is so you could have wall power when you want to upgrade your OS. If you don't have an extra sync cable or a friend with a virgin cradle and you need to sync while running on AC power, you might have to undo this modification or build in a switch to bypass it (very easy, email me if you need help)."

charlie

02-08-2002, 03:08 PM

Hi, it's me charlie

ctitanic, a few people have suggested that, its a very good idea. It would make it much easier to implement since you didn't have to solder to that small pin. I was in such a mad rush to try it once I saw how to do the mod that I didn't consider the traces on the pc board that hook up the ac adapter power to the comm socket. I've only read of one guy messing it up, i bet this would have helped him. I was going to update the page last weekend but I didnt have time. I'll probably get to it this weekend.

are there any other hardware hacks you guys want to see? maybe I can try to work some of them out.

about the 3800 cradle, I don't have a 3800, so thats not going to happen unless I can figure out a way to get my hands on one for a weekend.

--charlie reverte
[email protected]
p.s. lighten up rene, all of my friends thought it was funny..

ctitanic

02-08-2002, 03:15 PM

Peterwest,

That's not correct. Like I said before, you can take and jump the red cable from USB with the Red Cable of your power plug. During the installation what they will verify is the existence of power in the pin number one of the Cradle and you will have power in there. So do not worry about that point.

Maxor

02-08-2002, 05:40 PM

ctitanic

02-08-2002, 05:54 PM

No, the ipaq has it own circuit to charge the battery, I have seen an extension pack made to charge an ipaq with an out power of 9 volt. In this case the voltage coming from the usb port is 5 volt, the same that supplies the original power supply.

charlie

02-08-2002, 08:47 PM

As far as I know, lithium ion battery require circuit from the charger to give proper voltage info to the battery and keep charging it until voltage reach a certain point!

Wouldn't it do any damage to the battery if power just come from the USB?

Maxor

if you want proof, there are many aftermarket cables (I have one) that sync and charge the ipaq safely over the USB port. Ask anyone who has one and they will tell you that it is fine. This mod will enable your cradle to do the exact same thing. The only disadvantage to using USB is that since the current rating of the USB standard is less than the amount of current that your AC adapter supplies, it will probably take longer to charge your batteries. I don't have any actual data on how much longer. I have not noticed it really, but I didn't use the ac adapter for long. I'm pretty sure that the difference will be more than negligible though. This effect may be more noticable on a laptop than a desktop. Especially if you are using a usb hub without external power.

charlie

Kirk Stephens

02-08-2002, 10:12 PM

"Beat your kids"?
The guy who wrote this has poor taste when it comes to humor... :cry:

The author clearly wasn't serious, and even if he was no one would beat their kids with a cable. I found it rather funny.

klinux

02-09-2002, 12:02 AM

Does any body know how to make this mod for the (huge) Casio E-125 cradle ??

Trapperjohn

02-09-2002, 03:07 PM

Hi,
This is great! I was going to buy another ac adapter to have at work. But you have made that a moot point.
Thanks for your mod.

Trapperjohn :)

charlie

02-09-2002, 10:00 PM

Hi,
This is great! I was going to buy another ac adapter to have at work. But you have made that a moot point.
Thanks for your mod.

Trapperjohn :)

you're welcome, I'm glad I was able to help. did you have any trouble doing it?

charlie

NewKreation

02-18-2002, 05:55 PM

:D

That was easy!

Thanks to the detailed instructions (especially the part about tinning the bare ends first) I was able to modify the cradle with no problems.

The coolest part was to see the mechanics of the cradle. My 3635 is synching and charging - while my AC adapter is in my bag to take home.

Thanks Charlie Reverte and Frank Garcia!

ctitanic

02-18-2002, 06:01 PM