[Guide] Nexus 7 Wifi Fix

[theecatsmeow]

Are you among the many people to buy a fancy new Nexus 7, only to realize that the wifi reception on the tablet is comparable to a potato's? Or maybe you tablet took a tumble and now your bars have left you for dead? Well if either of these are are your case look no further.

This is a guide on how to fix the crappy wifi reception and transmission on your nexus 7.

What you'll need:
-Electronics opening tool (The kind meant for disengaging clips)
-Some small wire (I used 30 awg single-strand)
-Solder (And also preferably flux)
-Intermediate soldering skills

This guide will show you what I did to fix my Nexus 7's terrible wifi reception. One the tabs on my nexus was broken, causing a bad but still present wifi connection. Doing this will help you go from 1-2 bars to 3 or 4. For those more technically informed around 30-40db to 60-70db. When I look at my connection in dd-wrt the connection has gone from peaking at 20% to stable at 45% (the same as my laptop's connection mind you)

The magic thing to this fix? Soldering the points on the motherboard to the points on the case where the antenna is located. Normally this connection is with 2 gold tabs the touch the points on the back.

Start with the guide on ifixit.com. I tried to add a link but was not allowed too because I am a new member.
This is extremely easy to open and you would almost have to try to mess it up.

Once you have the tablet open you will see a few spots where there are the golden tabs that stick up. Also on the back there are contact points where these tabs meet. You will be joining the tabs to the pads with wire instead of just surface contact. Here you can see the side of the tablet where the wifi transmitter is. It is right of the battery and below the sticker with some barcodes. All you need to do is cut a couple wires an inch to two inches or so, and solder them to the tabs and then their corresponding pads on the backing.

I broke off my second tab as my first tab was already broken and no where to be found. I also added a little bit of hot glue to secure the wires and also to stop them from bridging the points.

This took me about 15 to open, do, and close up. When you are closing up the case just gently push the wires indside the case so they are not in the way of the clips.

I am not responsible if you mess up your device doing this. If you have any doubts please just send your tablet in for repair. That being said this is very easy and was of great benefit to me.

I tried to add pictures in the guide but since this is my first post I am not able too. I have them attached

 

[Clonetrone]

Very helpful! Thanks a bunch for this!

 

[theecatsmeow]

No problem. I was so frustrated with my tablets WiFi before I looked inside, and wanted to help others avoid the same difficulties. I think the tab was actually just wedged in place between the contacts,but still was broken. PS if you WiFi already works well this isn't going to help a ton. My friends nexus 7 has always had 4 bars in my house and mine use to only get 4 within a foot of the router. But if your tablet has bad WiFi this will most likely help.

 

[Clonetrone]

Will keep that in mind. This should be stickied.

Sent from my Nexus 7 using xda app-developers app

 

[bigbop]

No, please do not stickie this. What the cats meow has done is to de-tune the output of the wifi amplifier.
To put it simply, he should have just bent out the clips slightly to make better contact with the wifi antenna on the inside of the back cover.
By adding this wire, not only has the wifi RF amplifier been de-tuned due to some randome wavelength of wire added, but the reception will also suffer. It's also no longer FCC type approved and could be radiating spurious RFI around not to mention picking up RFI generated from the CPU and power supply circuits (around the area to the left in the image).

In layman's terms, the wifi radio is designed to transmit maximum power and receive maximum signal using the antenna connected via those two clips. It's a very specific match for this to happen. Modifying the connection by adding a length of unshielded wire screws up this match and can cause the output stage of the wifi transmitter to actually cut back its power due to this mis-match.
Any device that transmits radio energy in the US has to be FCC type approved and the testing is quite strict to ensure equipment doesn't radiate signals in a way that will affect other radio systems.

Owners of Nexus 7 devices should NOT make this mod. Just bend out the clips slightly and clean the contact on the antenna strip to ensure good contact. The contacts are made of phosphor-bronze and they can break easily if bent too much.

 

[b00mb00mchuck]

I almost agree with that de-tuned FCC mumbo jumbo

But I kinda did the same thing... But added an SMA connector and have hooked it up to huge 19dBi panel antennas and pulled WiFi signals from over a mile away....even posted a thread about it here.... And it works beautiful... With all sorts of antennas...

I agree that his method of adding unshielded lengths of wire isn't the "best" way to go about your business but with the broken pin he had in there he did the best he new how and made it work

 

[bigbop]

Yes, you used shielded coax and assumed the impedance of the external antenna is matched. Big difference with what thecatsmeow did.


Sent from my Nexus 7 using xda app-developers app

 

[theecatsmeow]

I understand the reasoning with the unshielded wire picking up interference and also the timing being off. Your are right, one should just bend the pins to get better contact with the pads on the back of the casing. That's actually what I set out to do. Even though technically my WiFi is now miscalibrated, the fact is that it is a drastic improvement over what it was. I am just trying to show people what I did to fix my problem. I will edit your information into my post and recommend that people try to bend the tabs if at all possible. However, being that my nexus 7 is 1 week old and I haven't even dropped it I am probably not alone with a having a broken tab.

 

[dottat]

See for me I stopped reading the op when he stated the signal went from -30-40 to -60-70. That statement shows a loss in rf signal.

If you had -30-40 to begin with you wouldn't have any WiFi problems.

Not a good idea to do this mod. Just the soldering and dissimilar metals alone make for impedance mismatches.

Sent from my Nexus 7 using Tapatalk HD

 

[theecatsmeow]

I have that listed the wrong way. I had -60-70 but now I have -30-40. No one said you had to do this mod. But for some like me who have a broken connector this could be helpful. The impedance of air is a lot more than the impedance of lead and copper.

 

[dottat]

An antenna is a closed loop. Impedance matters !

You would be better off finding the exact part needed for repair.

Sent from my Nexus 7 using Tapatalk HD

 

[swisstourist]

And where you can find these parts?Mr smart pant!

Sent from my Nexus 7 using Tapatalk HD

 

[davidoff59]

Seeing as its so new, what stopped you returning it for a repair under warranty

 

[nhutquang972012]

I has broke 1 of 2 golden tabs, but i still keep it. How can i reconnect this tab to the Nexus 7? Using glue? Is it a good idea? My wifi is very bad now...

 

[BrianDigital]

I wonder if the people having issues with wifi, might be due to having to many neighbors broadcasting on the same frequency and many on the same channel.

I recently bought a new wifi router just for this reason (shame the n7 doesn't have duel band, but my n4 does)

This has solved my issue completely, except for YouTube but I am suspecting g that might be out of my hands.


Anyone looking around for a new router I got this one from newwegg
Never heard of the brand but it's been great


http://www.newegg.com/Product/Product.aspx?Item=N82E16833315100

Sent from my Nexus 7 using Tapatalk 2

 

[bftb0]

I wonder if the people having issues with wifi, might be due to having to many neighbors broadcasting on the same frequency and many on the same channel.

Possibly - but it's way off-topic for this thread. The OP (and others) did repairs of broken devices where the external antenna was effectively disconnected. Nobody should regard the methods of this thread to be a way of *improving* their signal strength unless they are sure they have a broken device (or are planning on modding their device to add an external directional antenna)

For reference purposes, my (correctly functioning) N7 WiFi + WiFi router exhibit the following line-of-sight signal strength (observed using farproc's "WiFi Analyzer" app on the N7) :

-22 dBm @ 10ft
-33 dBm @ 20ft

The above values are the best-case that I observed; at the same locations I can observe up to 10 dBm attenuation simply due to orientation changes of the tablet. (That is expected as neither the router nor the tablet have isotropic antenna gain patterns - both amplitude and polarization)

The point of this is that even if interference is present, it won't effect the observed signal strength - and nobody should be using the hardware mods in this thread unless their signal strength is terrible - even when very close to the router.

The points made by bigbop earlier in the thread are well worth reading. The mod proposed by the OP should only be used in dire circumstances.

 

[bftb0]

I has broke 1 of 2 golden tabs, but i still keep it. How can i reconnect this tab to the Nexus 7? Using glue? Is it a good idea? My wifi is very bad now...

Yes... "glue" which is made from 100% solder.

What you should try to do is to create a fix that re-creates the missing "golden tab". It needs to be very conductive (that's why most glues are completely out of the question), and it should be ideally no bigger than the original. A very short piece of small wire could be used - emphasis on "short", as in mm, not cm. The further you depart from the original geometry, the worse your fix will be. (But even a bad fix will be better than what you have now - which is no antenna at all).

good luck

[Edit]
Here's an idea that might work - using a Fuzz Button. They have built-in compliancy and are manufactured in a variety of lengths and diameters. I suppose you could even solder the periphery of one to the remaining pad. No clue where to go to buy two or three or a dozen, though. Mouser Electronics maybe?

 

[nhutquang972012]

Yes... "glue" which is made from 100% solder.

What you should try to do is to create a fix that re-creates the missing "golden tab". It needs to be very conductive (that's why most glues are completely out of the question), and it should be ideally no bigger than the original. A very short piece of small wire could be used - emphasis on "short", as in mm, not cm. The further you depart from the original geometry, the worse your fix will be. (But even a bad fix will be better than what you have now - which is no antenna at all).

good luck

[Edit]
Here's an idea that might work - using a Fuzz Button. They have built-in compliancy and are manufactured in a variety of lengths and diameters. I suppose you could even solder the periphery of one to the remaining pad. No clue where to go to buy two or three or a dozen, though. Mouser Electronics maybe?

I went to welding shop and everything was solved, even wifi is better than before. Thanks for your help.

Sent from my Nexus 7 running Cyanogenmod 10.1 - Android 4.2.2 - Franco kernel r47 using Tapatalk HD

 

[BrianDigital]

Possibly - but it's way off-topic for this thread. The OP (and others) did repairs of broken devices where the external antenna was effectively disconnected. Nobody should regard the methods of this thread to be a way of *improving* their signal strength unless they are sure they have a broken device (or are planning on modding their device to add an external directional antenna)

For reference purposes, my (correctly functioning) N7 WiFi + WiFi router exhibit the following line-of-sight signal strength (observed using farproc's "WiFi Analyzer" app on the N7) :

-22 dBm @ 10ft
-33 dBm @ 20ft

The above values are the best-case that I observed; at the same locations I can observe up to 10 dBm attenuation simply due to orientation changes of the tablet. (That is expected as neither the router nor the tablet have isotropic antenna gain patterns - both amplitude and polarization)

The point of this is that even if interference is present, it won't effect the observed signal strength - and nobody should be using the hardware mods in this thread unless their signal strength is terrible - even when very close to the router.

The points made by bigbop earlier in the thread are well worth reading. The mod proposed by the OP should only be used in dire circumstances.

so i should read those points even though i no plans to hot glue some wires to my tablet. it might be off-topic for this thread, but since someone might read the general "fix bad wifi" topic thought id like to give me experience

can i ask you then why do routers have different frequencies they broadcast on, since everyone can be on one and not cause an issue then

i attached a screen shot, the one at the most left is my original wifi network the one at the most right is the new one, the middle one is my next door neighbor, and it will lower in DB while mine drops spuratically. now my new router is in teh exact same spot as the the old router.

Just saying sometimes some one doesn't need to reinvent the wheel when its not going to help

 

[bftb0]

so i should read those points even though i no plans to hot glue some wires to my tablet. it might be off-topic for this thread, but since someone might read the general "fix bad wifi" topic thought id like to give me experience

I'm not sure what you mean by the first sentence, but I will agree that the thread title is quite misleading, and possibly the reason why the thread got down voted.

@OP if you are reading, consider changing the title to "Broken WiFi Antenna Contacts Fix"

can i ask you then why do routers have different frequencies they broadcast on, since everyone can be on one and not cause an issue then

But in fact devices talking to the same router do interfere! A single radio channel is a shared medium analogous to an old-fashioned coax Ethernet or Ethernet hub - a collision segment. There is only a total bandwidth available for sharing amongst all devices on the segment/channel. The only reason that two clients talking to two different APs on the same radio channel is worse than two clients talking to a single AP is that in the single AP case, the clients are better synchronized in time by virtue of sequential ACK packet pacing by the AP (in addition to other AP coordination mechanisms). That coordination does not exit between unrelated APs on the same radio channel. So that's why there are multiple frequencies: to get away from your neighboring APs!

The other thing which is quantitatively different about shared radio channels in comparison to old-fashioned collision segments (hubs/thin-net coax, etc) is that the signal amplitude range in WiFi is huge: -25 dBm to -85 dBm is a factor of one million in signal strength. So, where even a tiny overlap/collision on an old-fashioned Ethernet collision segment would be fatal (all devices are nearly the same amplitude), that's not quite as true with WiFi: if both ends of an AP<->client station see each other at 30dB higher than all other stations on the same channel, so long as the packet has already started, the nearby signals literally smash the far away signals.

i attached a screen shot, the one at the most left is my original wifi network the one at the most right is the new one, the middle one is my next door neighbor, and it will lower in DB while mine drops spuratically. now my new router is in teh exact same spot as the the old router.

I don't doubt that some WiFi routers do a better job of their antenna design / matching than others. The thing to be aware of when making measurements is that RF propagation is a squirrelly thing - it is easy to get a 10 dB change in signal strength without even altering the distance from the AP - rotate your tablet slowly though different axes with that WiFi Analyzer app running and have a look. And of course, huge variations from place to place within your residence. ( If you were seeing BIG drops with your old router - say more than 20 dBm - then either it has hardware troubles, or possibly you are seeing a measurement artifact from non-WiFi radio interference (ISM band devices such as microwave ovens, portable phones etc) )

good luck