yashsingh1/xdaforums huggingface dataset:
[Epic 4G Accessories] protocol6v:
It did NOT affect the compass permanently. Once you remove it from the charger, there is no voltage passing through the coil, so therefore no magnetic interference.

The compass doesn't work while docked, but works fine when you remove the phone from the touchstone base.
[Epic 4G Accessories] m5james:
So why hasn't anyone done this yet to an Epic? From the sounds of it, it's a couple of wires, figuring out how to get the mounting plate adapted to the Epic and we're in business. I'm not willing to experiment with my phone, but I'm sure there are far more willing people than I. Since this thread was started, I'm surprised this hasn't been completely written up yet.
[Epic 4G Accessories] edscholl:
hmm, just picked up an epic yesterday. i think this would be easier than the evo mod - at least cleaner - the evo doesn't have exposed battery contacts, hence running wires to the usb port. the epic has the battery contacts exposed when you remove the back.

evo:

pocketables.typepad.com/.a/6a00d83451c9ec69e20133f117ebaf970b-pi

the epic has exposed battery contacts (first photo, 3 contacts on the left are exposed at the top when the battery is in):

fjallfoss.fcc.gov/eas/GetApplicationAttachment.html?id=1311529

much like the pre, so if you could modify the coil to place the touchstone contacts in the right place, this would be super clean:

pocketables.typepad.com/.a/6a00d83451c9ec69e20133f11807a0970b-pi

(i can't post links because i'm a "new" member, so copy and paste into browser)
[Epic 4G Accessories] icantdrawanime:
So, I bit the bullet and tried this... I got everything hooked up and verified that voltage was being delivered. Unfortunately, the touchstone delivers just too little voltage to charge the phone. It is 0.1v short (3.8 is required)...

=/
[Epic 4G Accessories] m5james:
The Epic requires more power than the Evo?
[Epic 4G Accessories] d94:
wierd, i thought the touchstone outputs 5v?

and if it is 3.7 is there anything that can be done to bump that extra .1v?
[Epic 4G Accessories] edscholl:
the info on the back of the phone says 3.7V, no?
[Epic 4G Accessories] d94:
nope 5v @ 1a
[Epic 4G Accessories] edscholl:
Alright, i looked at both my pre and epic batteries- they're both 3.7V Li-Ion batteries. Not sure why the touchstone would charge one but not the other. You sure you have everything connected right? :confused:
[Epic 4G Accessories] oktanedroid:
Not sure what you are talking about. The Touchstone coils output around 5V, which is what is needed for charging.

You cannot connect the touchstone coils to the lithium battery contacts. It needs to be connected to the USB power.

I can verify that touchstone works to charge our phones through the USB port. I get charging around 4.7V with 400-500mA current making it through the phone circuit.

I only hooked up the Vcc and Gnd (pins 1 and 5 for MicroUSB). I did not do anything with the data pin, which I believe may need to have special handling for the fast USB charging specification.

I did not actually take apart my phone yet.
[Epic 4G Accessories] d94:
WOOT we have confirmation that this works :D can you draw a diagram on which pins have to be connected to the +/- leads?
[Epic 4G Accessories] oktanedroid:
Here is a diagram of the connector:

http://www.kineteka.com/microusb-b.aspx

I'm still debating whether or not I want to take my phone apart and solder to the circuit board. It is tempting, but the disassembly of the galaxy phones is complex with all the sub-boards and switches.
[Epic 4G Accessories] d94:
While your correct that its a little complex and theres a few sub-boards and switches, me being a sprint tech and working on dozens of other samsung sliders, particularly the moment as of the last year and based on the pictures from the FCC website it's really simple to take this phone apart - just a few screws under the battery cover, the back pops comes off and boom theres the main circuit board with a few flex cables and antennas plugged into it..pop the connectors off and you have yourself the mainboard :)
[Epic 4G Accessories] oktanedroid:
Thanks, that's what I was hoping to be the case. :)

It should be as simple as soldering two cables to the appropriate spots on the MicroUSB header and then routing the wires into the battery compartment and out to the back cover.

I can confirm that the touchstone dock screws up your compass, at least temporarily. A warning message pops up regarding the magnetic field. Recalibrating seems to restore the compass. However, I did not test with the actual coil inserted into the case. The coil has metal disks that might become magnetized, potentially not allowing for recalibration unless you remove the back cover.
[Epic 4G Accessories] Roisen:
I attached the touchstone coil to the battery cover similarly to how the OP did in his picture and there was only a slight bump in the battery cover when it was put back on the phone. Not bad at all. Unfortunately the shape of the back of the phone makes it so that it does not connect well with the touchstone dock and it just barely stays in place when placed on the dock.

Assuming that the touchstone puts out 5V, then the easiest way to do this is to solder some small wires to the touchstone circuit board directly - bypassing the two metal pads that the pre uses - and running those wires through one of the tree holes that are clearly visible to the right of the SD card slot when you remove the battery cover. The wires could then be run to the USB port and soldered to the correct pins. Care must be taken to find the correct pins however because although microUSB has 5 pins, the USB port on the Epic has 7 pins connected to the circuit board according to the pictures in the OP's post.

If the touchstone puts out about 3.8V however, then I am at a loss. Connecting a power source directly to a battery (especially Li-ion) is very dangerous. We have no way of knowing what kind of voltage protection is included on the mainboard that protects the battery.

I will check the touchstone voltage and which USB pins to connect to tomorrow night (hopefully). I've just been too busy lately to get into a lab to check.
[Epic 4G Accessories] protocol6v:
The touchstone is NOT connected directly to the battery on the Palm devices. You can literally make a bomb this way. Do NOT try to apply voltage directly to the battery contacts.
[Epic 4G Accessories] edscholl:
oops, you're right- i looked closer last night and saw that the touchstone contacts go to the circuit board.

but let's not get crazy here- you'll overcharge if you leave the battery on the charger too long w/ a direct battery connection, but you ain't making a bomb... ;D

edit: i mean, batteries *can* explode of course, it's just really, really, really unlikely. iirc, most (all?) li-ion batteries have built in circuits to prevent it from getting too overcharged.
[Epic 4G Accessories] oktanedroid:
The touchstone does NOT put out 3.8V. It puts out almost 5V. It shouldn't be difficult to use a multimeter and figure out optimal solder points. Honestly, the hardest part is the disassembly and routing wires. Under no circumstances should anyone wire the touchstone directly to the LiIon battery. That is can be quite dangerous without a protection circuit.
[Epic 4G Accessories] protocol6v:
Maybe I over emphasized with the bomb part, but it is still incredibly dangerous and could end with injury if you charge a Li-ion batt directly.
[Epic 4G Accessories] d94:
The disassembly is super easy - 7 screws, just cracked it open - use a plastic tool to go around the edge of the back to get it off and put it back together in less than a few min:

deff liking the way samsung made this one, very easy to work with..only 2 ribbon cables and 1 antenna wire to get the board out. Then the SD card reader, 3.5mm headset jack and camera as usual are easily replaceable

so now that the hard part is out of the way if someone could figure out the optimal solder locations ill be happy to take it from there :D

PS sorry for the blurry shots, they were taken by an EVO lol
[Epic 4G Accessories] protocol6v:
You should have checked while you had it open. Just plug the charger in and use a voltmeter to check which pin coming off the usb jack is 5v.

Then just solder to that pin and solder the negative to any ground in the phone.
[Epic 4G Accessories] d94:
i would of if i had one on hand.lol ill have to try and grab one tomarrow

im guessing i put it on the 5v setting and use the + to find the 5v and the - for the ground? and how would i check for a ground
[Epic 4G Accessories] oktanedroid:
If you have an old analog multimeter put it on the 5V range. Most modern digital multimeters are auto-ranging.

Any ground on the circuit board should be interconnected, hence the term "common ground." There are many possible spots to solder your negative terminal wire. Pick the largest one since it is probably easiest to solder. You can consider using the solder point for the connector for the negative terminal of the battery.

Then, with your charger connected and plugged in, test to see which of the 5 circuit traces coming from the MicroUSB header shows +5V. Visually confirm that this corresponds to pin #1 in the pinout diagram.

Obviously when testing, be sure to only use the tip of your multimeter to prevent accidentally short circuiting across multiple points on the circuit board.

Some high-resolution photos of the area around the USB connector, front and back, would be helpful as well.
[Epic 4G Accessories] d94:
still havent gotten my hands on a multimeter..anyone else done this yet?
[Epic 4G Accessories] oktanedroid:
I haven't actually done the mod yet, but I did take the phone apart. It was actually not that difficult. Reassembly was more difficult for me since the case takes some force to snap back on.

1.) Briefly, after removing the back battery cover and battery, you will see 7 small Phillips size 000 screws (very small). Remove these and put aside in a place they will not roll/drop.

2.) Starting near the power button, carefully pry the plastic case around the edges using a thin plastic wedge. Do not use a screwdriver, as you will scratch/break something.

3.) Disconnect the small white antenna connector on the lower right-hand side.

4.) Disconnect the two small ribbon cable connectors to the motherboard. Very carefully pry these off from the side opposite the cable, being very very careful not to bend any pins.

5.) The circuit board is now free and will simply lift off. Be careful as the camera sensor is attached via a flexible ribbon cable, as is the headphone jack.

In terms of the +5V connection, there were not many options. Many of the components are very tiny and too hard to solder without specialized equipment. After checking many resistors, I didn't find a suitable one that would be any easier to solder than directly to the USB header.

That being said, in my opinion the easiest place to solder would be directly on the USB header itself. This is on the back-side of the circuit board. The correct pin is nearest the headphone jack. It is also indicated by a small diagonal gold arrow. You will need to carefully solder to this pin, and this pin ONLY. A short circuit here would be bad.

Carefully route your positive wire through the space for the camera sensor, and reassemble the circuit board. Now, on the circuit board there are many places to solder a ground wire. Take your pick. The easiest is probably one of the four solder mounts for the USB header. Either that or the headphone-jack side of the large resistor would be my picks, or any of the large ground buses (gold thick lines) on the board.

All the wires can then be routed through the potentiometer adjustment holes (R1, W1, W2), and the phone reassembled and screws reinserted.

From there, simply solder to the Palm Pre touchstone coil, and voila....you have wireless charging at almost 500 mA.

I should put the disclaimer that I have not actually done this mod yet, and any information above is based solely on my 15 minutes of tinkering. Use this information at your own risk, I am not responsible if you fry/brick your phone, or damage your compass.
[Epic 4G Accessories] Roisen:
I went into my lab all ready to do this mod and ran into two speed bumps. First, I was trying to confirm the voltage output and was seeing very strange results on the oscilloscope. It was pulsing once a second for one third of a second at about 500mV. I tried placing a resistor between the oscilloscope and the touchstone coil circuitry to see if it was trying to sense a load before it output it's voltage, but no go there. In the end I was unable to get the coil to output anything other than those slight pulses.

Secondly, After removing those 7 tiny screws, I was unable to get the plastic back off. The top part seemed to pull off very easily (note: be careful of the headphone jack. You'll need to pull the cover out a little to clear it when removing the back), but I just couldn't get the sides or bottom pried off.
[Epic 4G Accessories] oktanedroid:
Are you using the factory Palm charger with the Touchstone? You have to use a Palm charger or modify an standard microUSB charger in order for the Touchstone to turn on properly. The touchstone is expecting one or both (I forget now) of the data pins shorted together to enable fast charging mode.

You need to pry the back cover off, starting near the volume or power switch, whichever is looser. Slide a thin plastic shim in between, it will come off. Just be careful.

I will warn you in advance that it is not easy to solder to the USB header. You will need a very fine tip, and possibly some magnification depending on your eyes. You will need very thin and flexible wire and careful planning to route the wire in a way that the case with close, since the assembly wastes little space.

Good luck.
[Epic 4G Accessories] d94:
welp..ill have an extra epic to play with in a few days that i wont care if i fry so ill be doing this mod forsure and will take close up pix if all goes well!
[Epic 4G Accessories] d94:
WOOT IT WORKS! just did the mod..solder the positive to the trace closest to the headphone jack, and negative to the common ground and it works! i sanded down the back cover before putting the inductive charger in to make sure i have enough clearance..you can feel a little bulge on the battery cover but it fits snug and theres enough strength with the stock magnets to hold it on the charger, car included!
[Epic 4G Accessories] m5james:
This post is worthless without pics ;) I can figure out where the point is closest to the headphone jack, but I have no clue which is the common ground. I'd also like to see how people are removing the magnetic portion and attaching it to the Epic cover. I've got a Touchstone just waiting to be intergrated into my phone.

Have you noticed any affects on the navi, compass, etc once removed from the charger?
[Epic 4G Accessories] d94:
here's the pix :D

I sanded down the the back cover and drilled a hole for the wires, just because if they come out at one of the antenna holes the back cover doesnt come on all the way,I have yet to try the navi
[Epic 4G Accessories] m5james:
Thank you for this! I'm having a hard time distinguishing where you soldered the wires onto the phone itself, so hopefully it'll become more clear once I take the phone apart. Is the hole you drilled above the battery terminals on the phone itself? Which color wise was soldered to which terminal on the battery cover? Is there a writeup somewhere on how to disassemble the phone to do this? When it's on the dock and you have the USB charger hooked up to your computer, does it still allow transfering of files...ie does the charging, mass storage, etc screen popup? Highly unlikely since it's not a wired connection, but I figured I'd ask. Does the red charging light come on, or how did you confirm that this is proper voltage? Based on your last pic, it's sitting on the Touchstone but the charging light isn't on.

At this point I've removed the Touchstone stuff from the Palm cover and transferred it to the Epic cover since I see how you did it. I even transferred the 4 little metal discs...I wasn't sure if you did the same based on your pic. It gives a minor bulge, but the cover is staying attached. At least for the moment I have a stand!

Pic taken with my Treo 755p, that's been through hell and back (came out of my tankbag doing 80 one night!) and still kicking!
[Epic 4G Accessories] d94:
i updated my post to show which points are posotive and negative. you can only charge with the touchstone..cant do any data transfer and the light does turn red. And yes i did transfer the 4 metal disks, those are what keep the phone attached to the touchstone when charging. :)
[Epic 4G Accessories] m5james:
That is the one thing I forgot to get from my friend when he gave me his old Touchstone. I wonder if it's safe to get a replacement cable via eBay or if they're all just going to be generic MicroUSB to USB cables and won't have the shorted datapins that you are talking about.
[Epic 4G Accessories] m5james:
Thanks for doing that. I can see where the yellow is soldered to the outside frame of the MicroUSB connector, but the orange wire doesn't look like it's touching the far left connection on the MicroUSB wiring at all.
[Epic 4G Accessories] d94:
Yeah sorry for the crappy shot, i took it with my epic..its the glare from the flash, it is soldered you have to be very careful when doing it!

*FIRST POST UPDATED WITH PICS*
[Epic 4G Accessories] m5james:
So, I've got the Touchstone working, but I just thought of something. What would happen if I had the Touchstone going AND plugged into the MicroUSB on the phone so I can transfer pictures, use Droid2Desk, etc. I don't have a way to test it, but I'd like to know the possible dangers of having dual chargers going at the same time. The easy thing would be to leave it off the Touchstone, but I'm looking for more than easy.
[Epic 4G Accessories] edscholl:
in theory, you should be good. V = IR and all. given that it'd be a parallel connection, v would be constant, r is the same since you're not changing other components, which means your current would be constant.

but i ain't no electrical engineer, and i don't think i did that well in circuits class. :D
[Epic 4G Accessories] specialk0324:
Care to do this and I would gladly pay....this seems a little hard for my big hands....
[Epic 4G Accessories] m5james:
6'4", 245lbs...I did it. Just don't drink coffee beforehand :)
[Epic 4G Accessories] specialk0324:
Lol sounds like a plan...say a little prayer for me lol. Thanks to your very informative tutorial at least I'm pointed in the right direction.....
[Epic 4G Accessories] m5james:
I removed all the screws (don't forget the two shorty screws under the sticker) and used my debit card to start splitting the phone from the top and worked my way down. I removed all the external buttons and then used a small flatbladed screw driver in a light turning motion to remove the two connections on the board itself and then again to remove the camera itself so I had room to solder and feed the wire.

Find the smallest wire that you can. I used some very small speaker wire. The harderst time I had happen to be the easiest connection, which was the ground on the phone itself....I'd get it on there, then I'd be bending the wire around per the pic and the ground insisted on popping back off. By the way the wire route and are connected to the USB port, I made the positive lead shorter. Preload the wires by pressing the wires between the soldering iron and the solder itself so the wire would suck up the solder, then simply touch the wires onto the phone and touch the solder so it'd remelt onto the phones connections. Also, make sure that the ground wire is only touching the very corner of the connector. I let it run a little too long and it interferred with putting it back together as it wouldn't sit into the phone correctly, and the area where it sat was metal, so no shaving option there.

Before putting on the back cover, I drilled a similar hole from the backside at a 45* angle so the wire can come out. I'm not sure if it got noted here, but on the inside of the back cover is a little reinforcement block that stiffens the support for the MicroUSB connection. If you look at it closely, there is a little angle of plastic that will interfere with getting the cover back on since it hits the wires if you route them the same way as in the pics. I just shaved off that little angle and then some (the wire goes overtop a little hump on the circuitboard that there is no avoiding) with a razor blade or melted with the soldering iron and called it good.

My only gripe is that while using the Touchstone, a normal wall charger (came with my Moment) will work, the wallcharger to USB cord adapter (came with the Epic) will work as well, but using the USB cord alone and connected onto my PC, the Touchstone won't charge or the phone won't register it as charging. I still wonder what the output voltage is, so one of these days I'll kill the phone and then test charging times between directly connected vs on the stone (with the phone off the whole time) and I'll report my findings.
[Epic 4G Accessories] specialk0324:
Thank you for the additional info in last post....I will give it my best!
[Epic 4G Accessories] m5james:
So, not to deter people from doing this mod, but I had a major failure from doing this. Apparently the tension on the wires from being bent around the camera put too much pressure on the positive wire and broke the lead from the USB, therefore rendering my phone incapable of being able to charge, connect to the PC for transfering files, etc. Fortunately I was able to goto my local Sprint store, payed $35 for a warranty replacement since I'm in the 1yr time frame, and will have a new phone come mid week.

While I know it's not advised, I need to be able to charge my battery. I was considering leaving the wires and/or some alligator clips connected to the Touchstone and the Palm Pre cover that I have and remove the battery from my Epic for a few hours at a time in order to keep it charged until I get the replacement phone. I have a voltage tester in the garage, but for the sake of being sure, I'd like to know from those here who tested the battery connections before hand and let me know which two of the three battery connections I need to touch onto so I can charge the battery. To be safe, I will remove the battery from the phone each time, and unless otherwise directed, I'll only charge the battery for a few hours at a time or as needed in order to keep the phone on.

Let me know what you guys think so I can get this done, my phone is already into the lower half of the battery and this is my primary phone, so I need to be able to charge the phone in the meantime.
[Epic 4G Accessories] lepapirriky:
I'm gonna do this as well, I bought the charger and the cover for about 30 something bucks and an extra batt cover for my epic, that way I won't mess with the original one.

Here is my idea, where I really want to use this is at my car, I always wanted to have no wires at all when listening to music and of course keep my phone, but what is giving hard time is the fact that I won't be able to use the compass, now what is throwing off the compass are those 4 magnets on the cover, rght? If I remove them and use my cupholder that hugs my phone from each side, will that work? Or I really need the magnets as a switch to charge the phone?

I'm planning to open aparte the touchstone and as well add it on the cupholder, because again I only need this at my car, on my house I can use the cable, for the lack of an extra touchstone and magnets.

Sent from Maxwell's shoe