yashsingh1/xdaforums huggingface dataset:
[Galaxy S III Accessories] geolemon:
Note the four slugs in the battery door are not magnetic, so they won't interfere with the compass.

The only magnetics are in the touchstone itself.

That being said, the compass would logically be impacted when docked, similar to having the phone near a speaker, or other magnet.

Like any electromagnetic device operated in reverse, a coil has the potential to generate a magnetic field also - when voltage is supplied. However, if the coil is connected to the battery without any circuitry, it would drain the battery - that's partly what that circuit is for - to prevent that.

If you are observing magnetic interference when not docked, it would imply that the coil is energized. That would be bad, and indicate a defect with the circuit... somehow allowing leakage into the coil.

Note that circuit board is really really fragile - I cracked one just poking it back into the plastic hump on the sticker. If damaged, that could explain it.

However, a properly operating Palm battery door has no magnetic parts, either permanent or electromagnet - unless actually on the charger.

Note also (fundamentally): inductive charging inherently uses the principle of electromagnetic fields... the Qi mat and Touchstone both transmit wirelessly using a magnetic field. Electrons flow in a coil when placed in a magnetic field - that's fundamentally how it works. The compass would definitely be impacted while charging, regardless of technology or standard.

But also inherent in the technology and requirements (it would drain your battery if not true), that's the only time it would be impacted... for any inductive charging technology of any standard.
[Galaxy S III Accessories] garyd9:
I'm referring to the inductive battery back - not the charger. I don't think many people try to use their compass while the phone is laying on the charging mat. ;)

#1: just because samsung made it doesn't mean it works. I can post dozens of examples of things that Samsung has made that don't work properly, don't work to spec, cripples features, etc.

#2: The palm coil doesn't have magnets either (it had 4 metal discs that produce no magnetic field of their own - the magnet is in the base.) In the case of the palm, its the coil of copper wire that's causing the interference with the magnetic sensor.

So, I'll ask again - can't someone with the verizon cover please TEST both with and without the back cover to see if there's a difference with the compass. Please don't respond with assumptions - they are meaningless.

Thank you

Gary
[Galaxy S III Accessories] Jeurum_92:
I don't get this...

You don't need to align, the transmitter isn't much bigger then your phone, so no mis align possible. It's not that a NFC tag needs to be put on a exact spot of your back:p

Yes the Palm solution is cheaper, and in your case it is perfect for your car set-up.

But as I said, as a normal charger it is convenient. Place the reciever and up you go. No mods, no soldering or tape stuff.

I don't care if the QI is more expensive, because it doesn't costs that much. I like the looks of in my example the new LG QI charger.

Much nicer then the Palm and I can just place on it like a dock.
[Galaxy S III Accessories] eatonjb:
in that case, Yes, I have tried it, and the compass seems to work without a hitch. I do have the Verizon back, i just don't like it because it blocks the NFC.
[Galaxy S III Accessories] geolemon:
Exactly, the compass will work without a hitch. This is inherent in all wireless charging technology, or else you have a problem:
[Galaxy S III Accessories] garyd9:
Perhaps... or perhaps not. Note that the magnetic sensor in the SGS3 can also be used as a metal detector. I'm not fluent with magnetic theory enough to completely understand why (I can roll my own transformer coils, but only because I needed to understand for my radio license.)

I've confirmed that the coil interferes with the compass when both the 4 metal discs are removed AND when the coil/circuit is left unconnected and insulated (electrical tape covering the bare wire ends and plastic covering the rest of the coil/circuit.)

Perhaps it's the location of the magnetic sensor? I'm trying to position the coil low on the phone (closer to the USB port) and the little palm circuit board is higher - over the battery. So if the magnetic sensor is near the bottom of the phone, it would explain what I'm seeing and perhaps why some might not see it. I'll have to try again (when I have time) with the coil positioned higher...

Take care

Gary

---------- Post added at 05:02 PM ---------- Previous post was at 04:59 PM ----------

Interesting. I'll have to move the coil up high and retest.

If I had to choose between NFC and the compass, I'd have to choose the compass...
[Galaxy S III Accessories] geolemon:
I believe from my experience with my old HTC Magic and G1, actually what is used is the speaker, whose voice coil is inherently an inductive coil. Sound is an AC waveform, you can easily send a DC waveform to the speaker to energize the coil to set up a field - it's not a very good metal detector, but is good for party tricks. Clever app developer who figured this out for that "metal detector" app.

It's not a very good metal detector.

Same principles though.
[Galaxy S III Accessories] eatonjb:
well, as far as I know the Qi charging coil modified or the one that was showen eirler, lets you use NFC and charge via QI, so i am assuming that the compass will work.

I will keep you posted when I get it.
[Galaxy S III Accessories] garyd9:
I appreciate it. When you test, please be sure to test with and without the coil while standing in the same physical location and around the same time. That helps to both minimize the influence of varying external factors, and helps to make any difference more obvious.

Take care

Gary
[Galaxy S III Accessories] geolemon:
I centered my Palm Pixi parts on my phone so the slugs were centered (so I could mount on a charger in car landscape without any issue with magnetic balance), and mounted the Pixi back upside-down compared to how many people have been mounting it here. That puts the circuit board part over the NFC antenna, rather than the T-shaped foil shield that I was concerned would cause interference with NFC.

Silicon doesn't block radio waves, and there's even a good size pure open gap between that board and the foil shield. so NFC can get to the antenna.

That being said - I think my approach was overkill. No one has said that their Palm parts blocked NFC in reviewing this thread.

I believe the issue with the Verizon door is that the foil shield blocks the whole battery area. The Verizon door has it's own separate NFC antenna below that, however our Sprint phones don't have a connector for that. I've wondered for a while if it would be a simple thing to run a foil jumper down to the battery terminals for the NFC antenna to activate the Verizon antenna.
[Galaxy S III Accessories] garyd9:
That's something I'd love to test if I could get my hands on a verizon sgs3 for 10 minutes (while I happened to have a multi-meter handy.)

There are 4 contacts on the SGS3 battery. Two are for battery discharge and are clearly marked (+) and (-). The contact between the (+) and (-) is used for charging the battery (probably along with the common (-) contact.) That leaves one unmarked contact on the battery which is likely used, along with the common (-) ground for the NFC antenna. It'd be simple to confirm that simply by testing the resistance (on a very low power setting!!!) between the two NFC contacts on the verizon sgs3 and the "extra" battery connector and the ground (-) connector.

So, if you lay your sgs3 face down on the screen with the back removed, and then take the battery out, you'll see the 4 battery connectors near the bottom of the battery "socket" above the SIM slot and sdcard slots (in the case of the sprint phone, there's no user-accessable SIM slot.) If you numbered the four battery connectors from left to right, you'd have:

1: unlabeled, unknown use (probably NFC)

2: (-) (likely a common ground)

3: unlabeled, used in charging the battery

4: (+) +3.8v (power) (I see 4.3v on a fully charged battery)

(Note: the (+) and (-) markings are on the battery itself - not on the phone.)

So, it seems to me that the "extra" contacts for the verizon back NFC antenna are the same as the "1" and "2" contacts referenced above.

THIS IS PURELY SPECULATION. IF YOU DECIDE TO TEST THIS WITH A METER, USE THE LOWEST POWER OHM TEST POSSIBLE TO PREVENT DAMAGE IF THIS IS WRONG.

I wonder if a verizon store employee would get suspicious if I started tearing apart their demo phones, pulling out the battery, and sticking multimeter probes in the back. ;)
[Galaxy S III Accessories] xceebeex:
I wish there were more options for just the receiver. I have tried to find someone selling just the receiver and I can't find it anywhere. I am ticked that I missed the two that were for sale on ebay.
[Galaxy S III Accessories] jetjaguar:
Wireless charging mod issue

Ok. I tried the Wireless charging mod.

I used the following items:

1. Palm Touchstone wireless charging dock.

2. Palm Touchstone AC adapter and USB cable.

3. Palm Pixi Touchstone back cover.

4. Wire from old USB cable to connect the receiver to the phone.

See pics of these items attached.

My build steps.

1. I applied Pixi Touchstone receiver to the inside of the back cover of my Verizon GS3 i535.

2. I soldered the two wires from the USB cable to the connectors of the receiver.

3. I placed the back cover of the phone on the Palm Touchstone transmitter/dock/wireless charger and checked the volts DC produced. The receiver was producing 5.65v DC.

4. I soldered the two wires to the connectors on the phone. Positive to the top, negative to the bottom.

5. I placed the back cover on the Touchstone transmitter to test if the phone began to charge.

It was at this point that the "Wireless charging" notice popped up. Then went away. Then popped up again. Then went away. Etc... Video here (please ignore the talking in the background, just my wife complaining about my son's friends).

So it's working but not really. It appears that the Pixi receiver is producing 5.65v DC but for some reason it isn't constant I guess.

Anyone have any ideas or suggestions what might be happening here?

Jet
[Galaxy S III Accessories] maajka:
That would happen on my palm pre when it's not perfectly placed on the touchstone. Sometimes too high or low, or if I place it with an angle. But pre had this perfect magnetic position when to would just 'pop in it's place', if you know what I mean.

So I would assume the receiver is not on the perfect place relative to the touchstone. Or somehow it's too far away from it. Try to move the phone up and down, left or right, to see if it stays charging. It must have something to do with the strength of the signal (induction).
[Galaxy S III Accessories] AnaMayShun:
Is the QI set from MobNnovate the only set available right now? $85 is a bit much for me at the time.
[Galaxy S III Accessories] eatonjb:
Remember that is the coil AND the charging base. The Verizon one is about $50 and then you have to add a $60 base to that. So no, it's not bad. Can't wait to get mine.

== Yea.. I tapped that!
[Galaxy S III Accessories] AnaMayShun:
Are you able to use the powermat base with it? I see those for like 20-30. And someone posted in here they got their Verizon back for 39.99.
[Galaxy S III Accessories] maniac2k:
Verizon wireless sells the back cover for $40 and the mat for $50 plus taxes.

So if you need both, $85 shipped is a good price. Remember to, the verizon one uses its own extended back cover which wont fit almost every case. The aftermarket one fits under the stock cover.
[Galaxy S III Accessories] maniac2k:
Has anyone tried this one on ebay from hong kong for $30? Its based off the touchstone and no mod is needed. Just pop on the replacement back cover. I wonder if the cover is stock size.

http://item.mobileweb.ebay.com/viewitem?itemId=150903840091&index=2&nav=SEARCH&nid=99716057927
[Galaxy S III Accessories] eatonjb:
that is just someone who did the Palm mod for you, it looks clean, and I am sure it will work, but again it's not Qi, so its your choice.
[Galaxy S III Accessories] maniac2k:
Yeah its touchstone but looking at the pic, it has a nice circuit board tail with connectors that go to the phone contacts. Not some hack with wires/etc.
[Galaxy S III Accessories] gemignani:
wow, looks easy to install...

i also have a brawn shaver, it comes with a wireless charger dock... do u know if this works?
[Galaxy S III Accessories] stu5797:
Thanks so much for that Link. I just purchased that touchstone modded back cover for $30. I hope it works well and the sellers rating is high. 30 is a very fair price for an amazing mod!
[Galaxy S III Accessories] axel06:
Qi Transmitter

Use the Energizer Qi. Buy energizer transmitter on eBay or Amazon. They work exceptionally well.

The Chinese Qi transmitter is a piece of junk. We finished testing 3 sample transmitters. They work intermittent for a charge and next test it goes on and off. The testing we did involved a total of 180-195 hrs each (x 3)and not acceptable.

Buy their receiver (it is working well) that lays on top of the battery, but use energizer or Panasonic. Verizon is a pain because it emits alarm when charging done. Remember- Powermat is NOT Qi! Neither is Touchstone !

In short: skip Chinese transmitter, but do use their Receiver
[Galaxy S III Accessories] xceebeex:
I would love to buy the receiver, but it is pretty impossible to find.
[Galaxy S III Accessories] maniac2k:
Seems like a good deal to me considering a stock back cover costs at least $10 by itself.

Let me know how it works once you get it.
[Galaxy S III Accessories] ultraviolet150:
Make sure the rounded magnet on the coil thats on the back cover of your phone isnt damaged. if that round magnet is missing/damaged it produces the connect-disconnect that you are getting
[Galaxy S III Accessories] jetjaguar:
Round magnet

Thanks for the tip but I'm not sure I understand. What round magnet are you talking about? is it on the circuit board for the receiver?
[Galaxy S III Accessories] android94301:
Very clever, just my stock mod, and they soldered two upright pins onto the contact points on the Touchstone circuit, which then stick into the charging contact points on the SG3. Seems like using copper tape ends up working just as well, without the need for complex soldering, but if you have the skills, this would be a good way to go.
[Galaxy S III Accessories] AnaMayShun:
Where can I buy just the receiver?
[Galaxy S III Accessories] mdcarter67:
What cable/power adapter are you using in your car? I have tried 3 different chargers in my car. They charge if connected directly to the phone, but not through the touchstone. The best i can get is the phone will flip back and forth between charge and discharge every half second. Yes, my pixi receiver is working fine, I've used it for months at home and the office. Of the 3 car chargers I've tried, one is .75 amp, another is 2.1 amp and the 3rd is unmarked.
[Galaxy S III Accessories] Jeurum_92:
Maybe at their site?:rolleyes:

http://www.yijieneng.com/en/Product_detail.asp?productid=750&classid=138

Just email them...

Send from my GT-I9300 with Tapatalk
[Galaxy S III Accessories] Tularis:
Hi everybody, I'm trying to use this mod in my S3, I bought both the touchstone "dock" and the palm back cover, I transfered the coil on to the S3 back cover but when I try to check the power (I connect the dock to an USB port and put only the back cover with the coil on it) with a multimeter, it always says 0 V :S.

Do I need to put a load?

It should charge if connected to an USB? or it only works when connected to the wall plug?

If anyone could help me I would be very pleased.

Thank you in advance!
[Galaxy S III Accessories] patpatpatpang:
Hi Guys,

This is a back cover in cheapr price US$28 below

http://www.ebay.com/itm/200821599660?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

You can also find US$55 with full set of back cover + touchstone below.

http://www.ebay.com/itm/200819474696?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
[Galaxy S III Accessories] Fallon:
It should be reading a little over 5v, 5.4-5.5v or something. I left my multimeter on AC mode instead of DC which caused me all sorts of confusion. The Touchstone is pretty finicky on what power & cable it will like I hear (I haven't had problems with the couple of chargers I tried, once I figured out I forgot my multimeter on AC). I think it just want's the data pins shorted together, which many micro-USB chargers do by default, but your PC won't do. I believe the coil really won't work or work well without that metal foil cover over it.
[Galaxy S III Accessories] Tularis:
Thank you Fallon for answering. Definetely Im not using AC mode on the multimeter and Im using the metal foil the palm back cover brought. My last chance is try with the wall plug and check...
[Galaxy S III Accessories] garyd9:
It needs a wall plug. The one that comes with the phone would work, as would an iphone plug (putting in a USB -> microUSB cable instead of the iphone cable.)
[Galaxy S III Accessories] Tularis:
Thank you for the response, Ill try ASAP and comment.
[Galaxy S III Accessories] Jeurum_92:
The thing a Palm charging method stops me is that it has that angled charger...

I use a Rock case and with cases the magnet is not strong enough I read, maybe someone can confirm or decline that?

Don't want to remove my cases if I want to charge...
[Galaxy S III Accessories] danwooller:
It will charge through a Rock case, but the metal discs need to be set perfectly and even then it will only just grab on
[Galaxy S III Accessories] thacounty:
Do you have one of these? I take my back off my phone daily to change batteries. Would this create a problem? I also use a case intermittently, will I have to take it off to use it?
[Galaxy S III Accessories] xceebeex:
I have tried asking him when more of these will be available, but he has not responded. I can't find them anywhere else either.
[Galaxy S III Accessories] android94301:
Mine works fine with Rock case

My Touchstone mod works fine with the Rock Case, doesn't fall off the charger. The trick I found was to replace the metal disks with similar sized neodynium magnets, and it holds fine even through a thicker TPU case.

See my post: http://xdaforums.com/showthread.php?t=1877191 which I'll be updating in a couple of days with new tricks!
[Galaxy S III Accessories] nerys71:
damn answers one of my questions. I can use the phone without my hybrid case (plastic and silicon hybrid) and apparently it won't work over that 1/4" distance. Grrrr too bad. wireless charging would SO rock.

I wonder what is the smallest coil you can use to do this? maybe I can build the coil into the case itself. ie wire the phone ports to the case ports and the case ports to the coil or something like that ?
[Galaxy S III Accessories] aeron16:
I have this combi.

Chinese qi receiver with energizer qi pad.

You do not need to change your case, as the receiver sits on top of your battery and inside the battery door.

However, if you change batteries frequently you just need to remove the receiver, then place it in position again on top of the battery after you replace the battery.
[Galaxy S III Accessories] eatonjb:
I was thinking of somehow taping it to the door so i dont have to sweat that.

I am also thionking of rigging one so I can use it on a large battery, but I am worried that if it charges slow, a large battery might take FOREVER!
[Galaxy S III Accessories] xceebeex:
Where did you get the receiver only?
[Galaxy S III Accessories] kms108:
This is probably the thinnest inductive charging receiver coil available, it's only available in china.
[Galaxy S III Accessories] thacounty:
How much? QI compatible? Works through case? Has tape to stick to back cover?
[Galaxy S III Accessories] Tularis:
Ok, I have checked with the wall plug and now it works properly, thank you very much.
[Galaxy S III Accessories] kms108:
price depend on the quantity, this is for the qi standard, you will need to use double sided tape, not sure about whether it will work through the case, It's just the coil, does not include the pcb, the actual s3 pad will work through case, I have a leather type case about 0.5mm thick, the charging still works.
[Galaxy S III Accessories] thacounty:
Much appreciated.
[Galaxy S III Accessories] nerys71:
not thickness but SIZE. ie length and width. how large is that chinese pad?

I may be changing cases. found a GORGEOUS looking bamboo case I ordered last night. will see how that one goes.

one of the vendors said he will test how "thick" the back can be before it stops working. we shall see.
[Galaxy S III Accessories] xceebeex:
I am still hoping someone finds somewhere to buy that Chinese qi receiver that just attaches to the battery terminals as a plug and play type thing. So far that one guy had 2 for sale, but I have seen nowhere else where you can get them.
[Galaxy S III Accessories] kms108:
If you search there are 3 people on this thread that sells them.
[Galaxy S III Accessories] xceebeex:
I have found two. One only had two available at the time and every time I ask when he will have more I get no response. The other that I emailed would only sell as a package, meaning both the receiver and the base (which I don't want).

I am not sure who the third is. If you don't mind PMing the third person to me that would be great.
[Galaxy S III Accessories] kms108:
see photo.
[Galaxy S III Accessories] AnaMayShun:
I emailed one company, no response. And I left a comment on FB for MobNnovate and they said they're out of them.

I also just want the receiver.
[Galaxy S III Accessories] kms108:
which company is this that you emailed.
[Galaxy S III Accessories] nerys71:
wow thats pretty small. but that is just the coil right you also need a pcb to go with that? interesting.

I want to add wireless charging to my defy xt on republic wireless. its water resistant but you have to "break" the water resistance to charge the thing. if I could fit this inside the water tight cavity with the battery then I could charge it without breaking the water resistance of the phone.
[Galaxy S III Accessories] kms108:
not a easy mod to do, the defy is rather small and tight fit.
[Galaxy S III Accessories] AnaMayShun:
Shenzhen Yijieneng Technology Co

http://www.yijieneng.com
[Galaxy S III Accessories] kms108:
I got reply from them, and went to see them.
[Galaxy S III Accessories] torkiaz:
I e-mailed the three contacts on the side yesterday and still no response. Any idea how much the transmitter costs though?
[Galaxy S III Accessories] AnaMayShun:
Can you tell me what email you used? I had a China@......com one that popped up. Also, did you buy just a receiver from them?
[Galaxy S III Accessories] kms108:
I got lots of stuff from them, transmitter, receivers, coils, and other qi stuff.
[Galaxy S III Accessories] AnaMayShun:
I take it, they're reasonably priced?

Also, how long did it take for them to respond to our email?
[Galaxy S III Accessories] kms108:
they are only reasonable if you buy in large quantities, over hundreds.

it takes less than a day for them to repond my emails.
[Galaxy S III Accessories] Jeurum_92:
I got no respons from them, also their MSN adresses are always offline.

Too bad because I want to buy stuff.

Send from my GT-I9300 with Tapatalk
[Galaxy S III Accessories] lmclaurin:
Check Ebay. Just posted mine. Little more expensive because I did not buy in quantities of 200 or whatever ridiculous number. I found someone to ship me a 5, and the only way I'll be able to get more is to buy in large quantities, which I really don't want to risk.
[Galaxy S III Accessories] AnaMayShun:
Are you using the Energizer or LG transmitter?
[Galaxy S III Accessories] lmclaurin:
Energizer. I bought them when they were 19.99 a week and a half ago.
[Galaxy S III Accessories] AnaMayShun:
And they don't chirp when the charging is complete? I don't want to have to listen to that overnight.
[Galaxy S III Accessories] kms108:
i'm the third.
[Galaxy S III Accessories] mitch27:
Took a while, but I just picked one up for $12 ($18 with shipping). Been waiting for a good deal for a few days now :good: