[smithmal]

From what I've read, owners that have acutal shorts in their wifi signal have extremely bad wifi performance. Definition of extremely bad = tablet loses signal when is 6 feet or more from the router. In my opinion, your wifi performance is pretty standard for the v88 (i.e. loss of stability when the signal strength is -70db or more). For this reason I would think tinkering with the ground or the wifi solder point would improve your wifi performance.

smithmal

 

[hercsi]

From what I've read, owners that have acutal shorts in their wifi signal have extremely bad wifi performance. Definition of extremely bad = tablet loses signal when is 6 feet or more from the router. In my opinion, your wifi performance is pretty standard for the v88 (i.e. loss of stability when the signal strength is -70db or more). For this reason I would think tinkering with the ground or the wifi solder point would improve your wifi performance.

smithmal

Sorry for the late reply; I will definitely do so.

 

[PseudonymSA]

Hello everyone, I've got what I think is a V2 Chuwi v88. I've removed the backplate and found a dead short between all the points circled in red in the image. So my question is: what is the actual antenna? Is the gold-ish PCB on the right the antenna? Or is the coax cable actually the entire antenna? The second question is: So then which ground wire do I de-solder?

On an unrelated note: what ROM do you, clearly knowledgeable people, use?

Thanks

 

[Sureshk13]

Hello everyone, I've got what I think is a V2 Chuwi v88. I've removed the backplate and found a dead short between all the points circled in red in the image. So my question is: what is the actual antenna? Is the gold-ish PCB on the right the antenna? Or is the coax cable actually the entire antenna? The second question is: So then which ground wire do I de-solder?

IMG_20140313_205617.jpg

On an unrelated note: what ROM do you, clearly knowledgeable people, use?

Thanks

To answer your questions:

Q: What is the actual antenna?

A:

Both pcb's are the antenna for wifi and bluetooth respectively as above. The coax cable is not the antenna since its shielded.

Do you mean you found a short between point A and B as shown above? I presume you're using a multimeter. Lets go through the steps.

• You will need to desolder both point A and B from the antenna and then only measure the continuity of the cable. This is because the patch antenna design is a loop and will show as a short. If there is no short, you may solder the coax cable back to the antenna and you're good.
• If there is a short, the problem could be either
• A: there is a short at the motherboard where the coax cable is soldered (between signal and ground). This can be easily identified visually OR
• B: the coax cable has melted and shorted the signal and outer shield during soldering (bad solder job). To identify this you will need to desolder the coax cable from the antenna AND from the motherboard and measure it. This was what happened to me. I replaced the cable with another coax cable I had (initially) and then modded it some more. (will post pic later) OR
• C: the motherboard itself is shorted between the signal and ground, then you're basically screwed!

If you're going to desolder the coax cable, please do it fast or risk melting and shorting the cable. If you're going to desolder the coax cable from the motherboard, please do so only if you're comfortable with surface mount soldering.

Q: Which ground wire do I desolder?

A: Although i advise against desoldering the ground wire, if you must do so its at the ground wire soldered to the motherboard (not in the pic). I will post a pic later...

On a side note, why are you doing this? You had not mentioned it on your post. Are you getting bad signal strength??

 

[PseudonymSA]

To answer your questions:

Q: What is the actual antenna?

A:

Both pcb's are the antenna for wifi and bluetooth respectively as above. The coax cable is not the antenna since its shielded.

Do you mean you found a short between point A and B as shown above? I presume you're using a multimeter. Lets go through the steps.

• You will need to desolder both point A and B from the antenna and then only measure the continuity of the cable. This is because the patch antenna design is a loop and will show as a short. If there is no short, you may solder the coax cable back to the antenna and you're good.
• If there is a short, the problem could be either
• A: there is a short at the motherboard where the coax cable is soldered (between signal and ground). This can be easily identified visually OR
• B: the coax cable has melted and shorted the signal and outer shield during soldering (bad solder job). To identify this you will need to desolder the coax cable from the antenna AND from the motherboard and measure it. This was what happened to me. I replaced the cable with another coax cable I had (initially) and then modded it some more. (will post pic later) OR
• C: the motherboard itself is shorted between the signal and ground, then you're basically screwed!

If you're going to desolder the coax cable, please do it fast or risk melting and shorting the cable. If you're going to desolder the coax cable from the motherboard, please do so only if you're comfortable with surface mount soldering.

Q: Which ground wire do I desolder?

A: Although i advise against desoldering the ground wire, if you must do so its at the ground wire soldered to the motherboard (not in the pic). I will post a pic later...

On a side note, why are you doing this? You had not mentioned it on your post. Are you getting bad signal strength??

Thanks so much for the reply. To answer your final question, I do have very poor signal strength. Signal drops 2-3 meters away from the router.

I have a short between every combination of every wire that I circled in red, including A and B. I assume that is because the bluetooth and the wifi antennas have a common ground?

So you say that the antenna itself is a loop? So testing the continuity with it soldered is completely pointless, silly me. I'll have another look at the board when I have some free time in the near future then I'll post my results.

Thanks again for your help

 

[Sureshk13]

Thanks so much for the reply. To answer your final question, I do have very poor signal strength. Signal drops 2-3 meters away from the router.

I have a short between every combination of every wire that I circled in red, including A and B. I assume that is because the bluetooth and the wifi antennas have a common ground?

So you say that the antenna itself is a loop? So testing the continuity with it soldered is completely pointless, silly me. I'll have another look at the board when I have some free time in the near future then I'll post my results.

Thanks again for your help

Is line of sight obstructed? How bad is the signal strength drop??

Yes, they have a common ground. As mentioned, you will need to desolder the antenna before measuring.

Also, here are the locations of the connections on the motherboard:


Could anybody help me out here? Could anyone try transferring a large file (say maybe 200mb and above) through the network share and post the average transfer rate (and also if connected in WiFi g or n). Preferably very near to the router so that the WiFi signal is excellent. Thanks in advance!

 

[Jneow]

Is line of sight obstructed? How bad is the signal strength drop??

Yes, they have a common ground. As mentioned, you will need to desolder the antenna before measuring.

Also, here are the locations of the connections on the motherboard:


Could anybody help me out here? Could anyone try transferring a large file (say maybe 200mb and above) through the network share and post the average transfer rate (and also if connected in WiFi g or n). Preferably very near to the router so that the WiFi signal is excellent. Thanks in advance!

Hi Been having bad wifi problems as well tried to fit in an antennae from an old router i had without much success. So it appears I may need to solder the ground wire as well as the main wire(wrapped inside). Can you help me indicated which points to solder for both ? Thanks in advance