MODIFICATIONS (& DISCUSSION THEREOF)
Please do not try using the cover as the antenna as it's gounded - even if it wasn't, this device was not made with that in mind
BEFORE ANY SOLDERING OR OTHER HARD TAMPERING, PLEASE TURN THE POWER TO YOUR MOTHERBOARD OFF
ANYTHING CLOSER THAN 1/4" TO 1/2" TO THE BACKPLATE OF THE PRIME WILL EXPERIENCE THE SAME SIGNAL DEGRADATION AS OUR CURRENT STOCK ANTENNA - BE IT INTERNAL OR EXTERNAL
xach said:
Hi all,
i've another method of fixing this wifi/gps issue without any soldering work. Basically i slotted in a small thin piece of plastic under the wifi/gps PCB (where the gold plate is) to get a better connection with the pogo pins. However, this can cause the PCB to be slightly bent and im not sure if there are any long term ill effects.
After this i'm getting better WIFI signal than my HTC Desire and managed to lock on to 9 GPS satellites (previously ZERO) in a semi open place.
The increase in signal is also the same as when i attach a wire to the pogo pin. WIFI performance at long range is still sucky but this definitely helped with the GPS signal.
Insert plastic tab as shown in red circle..i pushed it all the way in until the white piece of plastic cannot be seen. Did it for all three gold plate connectors (WIFI MAIN, AUX and GPS)
sorry i dont have a screenshot of GPS signal yet.. will post it in when i do.
Transformer Prime slightly open (pogo pins not connected)
Transformer Prime closed and assembled.
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dpwhitty11 said:
Here's the dpwhitty11 method:
Solder a thin wire onto wifi pogopin (which in my case got rid of the pogopin.... lol whoops. Doesn't matter though). Then route wire out thru mini HDMI-out.
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Erusman said:
Concept in my mind atm is drill
hole through back of prime to meet pogos. Solder on some antenna.
My prime is always in leather case so that would be cool.
Or play around and solder connection to factory wifi antenna. Bypass the
pogos.
...
Alright guys. Just got done doing a bypass of the pogos. I soldered some
wires to the pogos directly to the wifi antenna. Did a cold reboot. snap shut.
First thing I tested was GPS, using GPS test. It sat there for 60 seconds
and I still had 0 birds in view. Took it outside and it did start to pick up
some sats but they came up slow. Must be the aluminum backplate
blocking the signal.
Wifi worked better than it did before. (lol probably because the primary
wifi antenna was now connected.) I think the secondary was the only thing
working on my prime before. I actually got 32mbs and 5mbs! Same
as all my other tablets. HOWEVER, soon as I started to walk away from
my router the signal degraded. Speedtest results went down the further
I walked away.
I took the prime outside in the same spot about 50 feet from router as I did
with the alligator clips connected the other night. I did have one bar. Instead
of full bars the other night. Speed was around 8-9mbs and 800k 1mb with
speedtest.
You can draw your own conclusions on what is going on....
Aluminum backplate is interfering with GPS and Wifi...
It works but the signal is weak.... WHY? Asus put the wifi antenna in a spot
that doesn't see its way around the aluminum backplate.
Pogo pins.. hopefully they will use soldered wires instead of pogo pins next
time. I can see these little things not connecting to copper plate so easy.
But nothing compares to the Wifi/GPS PCB (printed circuit board) flaw!
I laughed for hours after seeing how the copper etching wasn't even connected
in the PCB.
Alright well good luck everyone! I am not going to do a final mod for myself.
I usually have my tablet in a leather case all the time. So i am just going to
put some external antenna on this thing.
Erusman said:
Well what the hey. Finish my mods and prime is back together. I was just
going to wait to this weekend to finish it. But I wanted my prime back! Its
sitting all pretty in my leather case working great! Sorry its late and I didn't
take pics.
I just removed the PCB wifi in it. Removed the pogos. Drilled some holes
in backplate. Solder some solid gauge wire to GPS, Primary and secondary
wifi. Wires went out back. (about 5 inches in length).
While I was in there I took and tightened the screws for the display.
Guess what the small amount of lightbleed I had in the lower left hand corner
is 90% gone. (lol that must be the issue with the lightbleed!) I am too tired
to go back in and fiddle with it. Someone else can play with it.
Wifi is awesome. Walked all around my house and had three bars. GPS
worked and was fast. (maybe do a road trip in few days).
wgr73 said:
If I were you I'd trim your wires just 1-2mm outside of the case. It looks like they are hanging out several inches. Your signal will not change if you trim them, as long as the wire is exposed out of the rear case. I have tried different lengths and they have no effect outside of the case (also, you don't need the alligator clips on the ends).
Erusman said:
***Update***
Ok I finished my final mod. I made myself some mini wifi antenna and placed them in my case. The mini wifi antenna are composed of a thin straw surrounded by heat shrink tubing. Capped with a plastic hole plug. Wires that come out of my tablet are inserted in the straw. Heated with lighter and sealed.
The mini wifi antenna I can pull up or down out of my case to extend the WIFI range. I am pulling three bars at more than 50 feet away. Amazing!!
I had to laugh a little because my prime kinda looks like a little android with the antenna stickin out.
Erusman said:
Ok, I just finished up another mod to my prime. My goal was to be able to mount the prime in a vehicle and use it on the road. So i needed the best WIFI and GPS I could get. And I did it!
Meet Optimus Prime
...
I replaced the old mod with external SMA male connectors and was able to mount on some external WIFI antenna. Large ones atm. But I have some small 2.4ghz stubby antenna on order.
...
I still need to mod my leather case to be able to insert the SMA connectors in it. However, I noticed with just the SMA connectors sticking out and NO WIFI antenna attached I still get good WIFI
(Both Factory WIFI PCB removed with soldered connection to SMA's)
The WIFI range on this thing is AMAZING! Full bars every place in my house and even out in my yard! 50+ feet away from my router. I think its limited to the range of my router more than anything now.
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RipplingHurst said:
But I'm thinking rerouting the antenna to the headphones would work. Could the headphone wires work as the antenna, similar to the alligator clips?
Wordlywisewiz said:
Another idea would be to for an extreme antena would be to desoder the connections to the headphone jack then put a small wire from the wifi antenna to the headphone jack and sorry it lol then you can make a custom antenna with a standard 3.5mm connector
wgr73 said:
More data guys. So I've wired my gps connection to the headphone jack, close the prime and the results are below:
...
Prime closed, GPS connected to my earphone jack. Results = not the best by any means but its getting there. I will try alternate points.
wgr73 said:
I can manage 11-15 sats (12 locked) with my headphone mod
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janaha_ said:
Don't know what I hooked up to here, but it is ground.
5-6 birds and lock in about 10 sec with gps status.
Will test some more, and do a more permanent solution if it works OK.
If I remember correctly someone here asked if the pads that contact the antennas are conductive.They are on mine.Goes to backpanel.Ohm meter showed few ohms, but diode tester beeped.
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wgr73 said:
So guys I was able to get 16 satellites in view indoor and 18 outside. What I did was unsolder the pogo pin and solder a wire directly to the board! Check out the pictures.
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janaha_ said:
The connector pins are the same used on wifi cards and are not related to GPS (I had a pigtail? connector laying around and it didnt't improve my signal, nor wifi)
I too struggle with no gps birds and not the best wifi when moving away from the router.
Like others the wlan/gps PCB is faulty, with no connection on the wlan part.
I didn't want to solder anything in case I wanted to return it, so I used copper wire and tape
Wifi improved, but didn't go through the roof (maybe 2-3 mbit)
GPS found no birds(tried for an hour last night with no success.
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Erusman said:
look at this picture of Wlan antenna. Now look very closely at
what i circled in red!!! OMG! no wonder my wifi wasn't working!!! PCB has
design flaw!!! Its not even connected to the so called antenna! I used volt
meter to test as well. NO CONNECTION
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Erusman said:
This pcb is glued to front half of prime. Pogo pin pushes against copper pad
circled in red to make connection on this pcb. The connection suppose to
follow all the way up to the top of those thin soldered on copper antenna.
It DOESN'T. There is a gap in the design of the PCB. GPS side is completely
connected. Wifi side is not.
...
One thing is for certian. That PCB of the Left side Wifi is flawed. Never made
a connection. So that is why so many primes wifi suck. Only secondary
antenna on right side was working. Asus knows what primes (serial numbers)
have the flawed wifi pcb. They need to issue a press release and statement of
such! Its only right.
Erusman said:
I just want someone to test the gapped WIFI / GPS PCB. I have a feeling this PCB is doing NOTHING for WIFI.
I can't because I removed both my WIFI PCB on top and pogos.
Both WIFI PCB are glued down and DO come out very easy. You just have to take your time.
1.) Record WIFI db with WIFI analyzer and Speedtest) Factory.
2. ) Remove the right WIFI PCB. (One that doesnt have GPS with it and not gapped.)
This will leave the gapped LEFT wifi antenna still in tablet.
3.) Close up your prime and record results of only using the left PCB WIFI / GPS.
I can bet that you will get NO bars for your WIFI and you will get next to nothing with WIFI results.
Conclusion. Left WIFI/GPS PCB is not doing nothing for WIFI and the gap in the copper etching is a factory flaw.
Doktaphex said:
I guess everyone missed it when I mentioned that I had done a test with the main WiFi antenna connection covered with electrical insulation tape.
What happened in this situation was that I got almost no wifi signal whatsoever. So actually the Main antenna is pulling almost all of the signal and the AUX connector is just boosting it a tiny little bit.
...
yesterday I covered the connection to the main WiFi PCB with electrical insulation tape. When testing WiFi after this with only the AUX antenna, I got almost no reception whatsoever.
Therefore, the main WiFi antenna is working correctly.
Erusman said:
Thank you Dokaphex!! Then there it is. I bet you will find if you cover both sides of the WIFI PCB's with tape you will get same result. The LEFT WIFI PCB is doing nothing. Because with bare pogos not touching anything. You still get some WIFI. (I am talking no bars on WIFI bar) but like 5%.
Ruprect said:
Erusman, you need to get this through your head .... RF signals do not need a piece of copper to get from A to B. Propagation, for example, is the fact that there is a big gap between the tv station transmitter and your tv antenna. yes the tv transmitter has megawatts of power behind it but the signals jumps the gap yes?
THAT GAP ON THE PRIMARY ANTENNA IS NOT A FACTORY FLAW
It is designed that way because that gap has one side of it at ground and the other side of that finely tuned gap will 'see' a carrier wave of a predefined band of frequencies. When combined with the other circuitry in the wifi signal reception, it delivers an adequate signal to be further processed down the line.
IT is Designed that way, please drop the faulty pcb talk, it is ridiculous.
Erusman said:
Like i said I am layman when it comes to electronics. Thanks for the RF instruction. HOWEVER, I find it hard to believe you got WIFI from the Gapped PCB when others have not. Others have covered the RIGHT WIFI PCB all together and had nothing but the LEFT WIFI Gapped PCB working. They had no bars on their WIFI fan. Was getting minimal WIFI. WHY? Because the Left WIFI PCB is not working. I have taken out both PCB and I still had some WIFI as well. I was getting no bars with both WIFI PCB and same results as when only the LEFT WIFI PCB was left in. (Approx 5% of WIFI signal... NO bars on WIFI fan. Speedtest 1.8mbs 500k vs 32mb 5mbs) These are the tests we have done. I thank you for your input.
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micaman said:
OK, I am once again stating that I have no technical background with this stuff so call this theory ridiculous if you like but I think its the GLUE. Yes the amount of glue that is used to secure the PCB in place Its seems like it would be the only variable in everyone's tablet. The amount of glue and the placement (flow) of the glue would be very difficult to control in the manufacturing process, thus the variable in everyone's prime.
Now the amount/placement of glue is either causing variances to
(a)the physical separation from the aluminum backing or
(b)compression causing a better connection to the pogo pin.
In essence the glue is causing the same effect as the shim some are using.
Considering some have already tried bypassing the pogo and soldering directly to the PCB I'm thinking its (a)
Pics of the backside of the PCB would be great.
...
I lean towards (a) not (b).
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jdudb said:
Since there seem to be many theories why there is poor antenne performance once lowered into the recess of the back, I might as well put my theory forward. I think that there is just too much radio noise from the circuits and it is drowning out the signals from both the GPS and WIFI. Maybe the latest tegra chips have excessive electrical noise? Has anyone else thought of putting a grounded insulated shield between the antenna and the main board with holes for the pogo pins? Say a sheet of aluminium foil covered on both sides with sticky back plastic and a small portion left bare so that it can contact the edge where the copper tags are.
Ruprect said:
small piece of ESDS bag, I thought of using, but now I`ve by passed the pogo pins, I no longer subscribe to this theory
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Erusman said:
The copper loops on top are the antenna. And they are not grounded. Look at this pic. Where the copper loops on top go they have some felt material against the aluminum so it doesn't ground.
wgr73 said:
This has me thinking. Seems as though the OP has a bad PCB (Op, check the back side to make sure there is no trace going following the rear). The OP could do 1 of 2 things to fix his PCB, use a fiberglass pen to cut away at the PCB and jumper the contacts, or just solder around the PCB.
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Erusman said:
I hooked up two red clips to wifi pogo's.
I hooked up one black clip to gps.
I ran various tests. Wifi and GPS on. Everything is on par with all my other
tablets. 32mb 5mb wifi. GPS is up and running all birds 5 to 10 seconds.
...
Yep. My GPS didn't even work. Connected wire to pogo pin and had
all 15 birds in view with GPS test app. Took less than 10 sec.
...
Bluetooth? Well, bluetooth still had problems
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jupppo said:
Well, some bad news. I was assuming a bad connection to the pogo pin was the reason for the bad reception. This is certainly not the cae for my prime. I know also assume it is the back plate.
I cut a 9,5cm (half GPS wavelength) cable an connected it to the pin. Great reception, even better than before, although I am inside and no other GPS gets signal here..
As long as the cable was outside the case it was great, but then I put the cable in the case and the signal decreased.
When I even closed the case. The signal was completly gone until I opened it again.
Looks to me that the aluminium back side shielded the signal.
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mystkrh said:
I have a GPS repeater in my hanger at work, and I placed my transformer prime right under the unit with my phone in that spot all gps signals are ~50 in GPS tester. You can see in the pictures one is ok, I personaly think there is an AGC problem in the GPS receiver, and to test it I padded the signal with a anti static bad (we use this method to troubleshot gps antennas on aircraft) and when I did that you can see the 2nd photo of the best signal I think anyone has ever seen on a prime.
...
i just placed a static bag over the unit, I didn't put it in a static bag
AGC is Auto Gain Control its adjust the gain high at low signals and lowers the gain at high signals. If you have a strong signal with to much gain the signal will become unusable. I'm a avionics tech, I deal with radio's, gps rx's and that kinda stuff alot.
The pogo pin connection could be a problem but, but I really doubt it, they are getting a bad wrap in this whole thing. They really are not that bad of a connection as long as they compressed slightly when making contact.
The thing I worry about is the affect of the exposed signal with no shielding on the pogo pin at 1575mhz it doesn't take much to have a problem with reception.
clackity said:
Automatic Gain Control. It applies gain to the incoming signal to try to achieve a predetermined (or optimal) signal strength. But anytime you apply gain, you increase noise. The trick is to improve the signal more than you increase the noise.
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dpwhitty11 said:
Whoever it was who drilled the holes in his Prime, what kind of bit did you use?
Erusman said:
Just a normal metal cutting bit. The aluminum is very soft. Be sure you are careful with the shavings when you drill. You want to make sure you use a can of compressed air to get the metal shavings out of the tablet. Bit size was 7/32. You can go smaller if you want. Just depends on what kind of rubber gourment plug you want to use, and size of your wire.
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Doktaphex said:
So I've been making different antenna all day, but what I hadn't done was just sit the antenna in the open case whilst testing, I decided to do that. Results here:
...
As you can see, even with the antenna just sitting there in the case the connection is useless, same happens when connected to WiFi antenna, in the case, nothing much, move it out to the side, excellent connection in dB.
My current thought is to somehow stick an antenna where the speaker grill is already. At least that would save busting things up too much.
micaman said:
OK now watching that video (thanks by the way) i have to return to my initial theory that it must be the aluminum case that is causing an electrical interference with the antenna an not just blocking the signal. If the degraded signal was solely caused due to the antenna just sitting in the aluminum backing why did the signal improve whilst it was sitting on the keyboard which is also made of aluminum?
Videos courtesy of
Doktaphex.
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Doktaphex said:
My latest idea is running a wire the entire way round the Prime, basically where the screen sits in the case, so far so good. I have a loop of wire attached to the GPS pogo pin. In theory, it could replace that black plastic surround that's about 1 mm thick on the screen.
It was a pain in the ass to install as a quick dirty mod, but doing it properly with tape and such like would make it a breeze. So far it's looking pretty good.
...
All of a sudden though, from having good birds in view I've got nothing.
This has been confirmed to not work. I'm not sure about newer models or their claims to better WiFi.
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Erusman said:
Other option you guys might try which i am toying with is adding these Tyco Wifi Antenna. They are used in laptops but extremely thin. Heck i dunno you might not be able to drill any holes and place these powerful boys someplace in tablet and get excellent wifi. I have a few on order already.
http://www.amazon.com/gp/product/B00...00_i00_details
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green750one said:
What about using an antenna like this ... it's 2mm thick and might fit inside the case. Have no idea what reception would be like but it seems bit more designed than the stock antenna?
http://www.mightygps.com/oem/dielectricantenna.htm
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PersonOfKnownOrigin said:
I wonder if this could be useful
http://www.sti-co.com/antenna-produc...ransparent-gps
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Erusman said:
You could probably even cut yourself some copper strips and be fancy with the design and fit them around the entire plastic bezel on front. Then solder a connection to the pogos.
However, its all about if the signal is going to get in there. It may not matter how big of copper strip or Tyco antenna you but in there. The aluminum backplate may block it and you will get same results as factory antenna.
jchipper said:
i just ordered a PCB Copper FR4 Circuit Board .025" x 12" x 36"
http://www.ebay.com/itm/36037716592...:IT&_trksid=p398 4.m1439.l2649#ht_1295wt_1139
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junrider said:
I think with my idea of buy a thin copper sheet that is very filmsy. measure the the size of the contacts on the board, now double it. So if the contacts where:
[||||] you would need a copper strip of [||||||||]
fold the copper strip in half to form a <
Then take the outer end of the copper and put a light solder film, put some rosin flux on the contact, then take the side with the thin film of solder of your copper strip and place it on the contact and press the soldering gun on the strip and thin film of solder should bind the copper strip and contact without the mess of excess solder.
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Lock-N-Load said:
Really though, in the end, it seems if someone wanted to get really hardcore, they could dremel a slice out of the back that is tall yet narrow, go to home depot and get some plexiglass, sand it down to obscure the view into the device, and epoxy that in place and place the wire into that as a window. Totally possible IF you wanted to kick it up a few levels now that the hard work is done and shows an antenna wire can hep. Essentially steal Apples' idea but keep it simple and make it home grown.
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RipplingHurst said:
Now im wondering if we couldjust unplug the camera and use that opening where the wires would end. I could easily sacrifice the camera or the flash for such.
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buxtahuda said:
Here is a terrible drawing of my own personal idea for an internally retractable antenna similar to the straw-method that Erusman adopted as his final mod with his Prime/case combo. I'm currently just looking around and gathering my thoughts, but I hope to find a fairly compact, flexible, and lightweight telescopic antenna and place one or two of them just along the MoBo (underneath the bezel of the screen, but attached to backplate) with a hole cut out and insulated so that only the top two or three inches of the antenna will leave the Prime and without making contact to the backplate.
Really, I don't think this would do well. You'd really need antenna large(thick) enough for the GHz frequencies.
