[cLevel]

Hi everyone,

I got my U30GT-H (OEM) from Panada. I have to say that it exceeds my expectations. Now, for people with screen touch problems while charging, I think I have a solution.

Problem: When charging, the screen is unable to correctly map finger touches on the IPS screen. It makes navigation on the tablet next to impossible. Once charging is complete, and is removed, problem gone. Also, people may have intermittent symptoms during charging only, read further..

Cause: POS Power Supply

I originally thought there was a ground isolation issue with the barrel of the plug end (which is NEG-) contacting the metal accessories grill. (I still do, but another story.)

This metal accessories grill (the metal tab with all the ports for sd, hdmi, 2 screws, etc.) is connected (and grounded to) the long metal band that wraps around the tablet, which in turn, is grounded to the rest of the device. That's good.

Theory: Unfiltered EMI from the PS, even attenuated TI from the power cord itself (its an antenna too!) ground itself on the common (and balanced) ground of the tablet. This creates a very noisy electrical field that the IPS screen can not handle (its out of spec, because its a cube design flaw). That's bad.

What I did:
I originally thought by removing the metal grill and isolating the ground that this would fix the problem. Well it didn't, so back to drawing board, and time for another cocktail.

Time to look at the PS. I opened it up and well it was as expected. A cheap, badly soldered, linear power supply with a under performing transformer. VNom was 12.20 volts, during load (charging) -- 10.4 volts. It gets worse (ok non-techies - 10.4 is not that great), after about a few min, I hear a click from the PS board, and look -- wow 3.2 volts -- under charge.

I found a PS from a portable HD which was a 12V 3A. Cut the old cord off, attach old cord to new PS, and plug in and test. ALL PROBLEMS GONE. The new PS is holding 11.89V with load.. fantastic. I even put the grill back on, and still NO PROBLEMS. Warning: I do still think there is a design flaw with the power port hole being too small.. they (cube) needs to drill that hole LARGER so there is no secondary contact. Its a design flaw -- listening CUBE?

Please, I am only throwing this out there for the community to digest, and comment. My comments are without warranty, are without prejudice, and the views expressed are not endorsed by Cube. (sorry, I have to say it.)

View attachment clevel_ps_chopchop1.pdf

 

[antonywarsono]

my tablet with series u30gt-h, firmware 1.02, got this problem too. Can anyone solve the problem? because when charging, touchscreen out of control.

 

[dmagee]

my tablet with series u30gt-h, firmware 1.02, got this problem too. Can anyone solve the problem? because when charging, touchscreen out of control.

Throw your charger in the bin

Now buy a proper dedicated one and you should be fine. Same fault on the Cube U9gt2

Sent from Xperia Mini Pro ~ Ics Android 4.0.4

 

[alternativ]

I think, this threat shoult be moved to FAQ or pinned on the top, cos a lot of people have this kind of problem and ask for the solution.

 

[Tablet_Collector]

I think, this threat shoult be moved to FAQ or pinned on the top, cos a lot of people have this kind of problem and ask for the solution.

Good point, I will move to faq.

Jez

 

[antonywarsono]

@dmagee : which charger do you recommend? where to buy?
i'm already try to use this : http://www.cube-tablet.com/cube-u30gt-charger.html
Thanks you

 

[cLevel]

@dmagee : which charger do you recommend? where to buy?

I drove down to the thrift store and found an old Nintendo Game Cube PS. It was rated 12V 3.5A. I swapped the plugs and it works great.

 

[Nickos-V]

I drove down to the thrift store and found an old Nintendo Game Cube PS. It was rated 12V 3.5A. I swapped the plugs and it works great.

I would not use that for long term. Charging battery with high current will wear out the battery sooner. 3.5A is 1.5X 2A. 2A is max you should really use.

These tablets come with 7200 mAh battery (or 7.2 Ah). With 2A (per hour) charger, should take little over 3.5 hours to fully charge it. ie, 7.2/2 = 3.6 hours With 3.5A takes, 2.06 hours. ie, you are fast charging with 3.5A. ie, slow charge is usually close to 4 or more hours.

Battery will last longer if you continuously, without draining, slow charge it. I would suggest not going less than 3 hours max for charging. 2.5A is probably the max I would go with for charger. That is really pushing it. 2A, 1.5A and last choice 2.5A.

With my 12V 2A charger, the battery gets fairly warmish. I can only imagine how hot your battery is getting with 3.5A.

Later,

 

[CoreyPL]

I would not use that for long term. Charging battery with high current will wear out the battery sooner. 3.5A is 1.5X 2A. 2A is max you should really use.

These tablets come with 7200 mAh battery (or 7.2 Ah). With 2A (per hour) charger, should take little over 3.5 hours to fully charge it. ie, 7.2/2 = 3.6 hours With 3.5A takes, 2.06 hours. ie, you are fast charging with 3.5A. ie, slow charge is usually close to 4 or more hours.

Battery will last longer if you continuously, without draining, slow charge it. I would suggest not going less than 3 hours max for charging. 2.5A is probably the max I would go with for charger. That is really pushing it. 2A, 1.5A and last choice 2.5A.

With my 12V 2A charger, the battery gets fairly warmish. I can only imagine how hot your battery is getting with 3.5A.

Later,

3.5A is the max that charger can produce. It doesn't mean that tablet will use it all

It will use as much, as it needs, nothing more. Cube uses 1.1-1.5 while charging, depends if you are using it or not. Another example - my PC PSU is maxing out at 54A for 12V rail (~650W). It doesn't mean that my computer gets more juice than needed. It actually uses around ~320-350W while running games, so maxing out around 29A. 2A amperage should be optimal for Cube. I saw one connected to 8.5A regulated PSU and still, Cube was only draining 1.1A from it.

 

[spookydad]

I just received my Cube this morning.. It was shipped on friday July 20th and is an -H model. It doesn't have the screen jumpiness problem.

Neil

 

[tortellini]

Hi
same screen issue, but after flashing Evolution 1.0.1 Jellybean, the issue seems to be gane
any other feedback ?

 

[jackHFS]

I still have screen problem with evo jellyean update and I've also purchased a new power supply to no prevail. However I have just noticed that if you touch the metal band which runs around the device the screen functions normally. Anyone who knows about electronics have any ideas why this might be? Also when I first bought the new charger it initially solved the problem however after a few days it came back again???

 

[jimac]

I still have screen problem with evo jellyean update and I've also purchased a new power supply to no prevail. However I have just noticed that if you touch the metal band which runs around the device the screen functions normally. Anyone who knows about electronics have any ideas why this might be? Also when I first bought the new charger it initially solved the problem however after a few days it came back again???

my money is on:-
" I do still think there is a design flaw with the power port hole being too small.. they (cube) needs to drill that hole LARGER so there is no secondary contact. Its a design flaw "

 

[dmagee]

my money is on:-
" I do still think there is a design flaw with the power port hole being too small.. they (cube) needs to drill that hole LARGER so there is no secondary contact. Its a design flaw "

I can tell you know bin your supplied charger and buy a proper dedicated one. The supplied chargers are awful.

Two tablets for me now with the same issue until I replaced chargers!

Tapatalk 2 from Sony Xperia Mini Pro Android 4.0.4

 

[edcox1234]

So i have the same issue! Can you tell us the model number of the ps you found? thx. ed

 

[edcox1234]

I just received my Cube this morning.. It was shipped on friday July 20th and is an -H model. It doesn't have the screen jumpiness problem.

Neil

 

[edcox1234]

Hi everyone,

I got my U30GT-H (OEM) from Panada. I have to say that it exceeds my expectations. Now, for people with screen touch problems while charging, I think I have a solution.

Problem: When charging, the screen is unable to correctly map finger touches on the IPS screen. It makes navigation on the tablet next to impossible. Once charging is complete, and is removed, problem gone. Also, people may have intermittent symptoms during charging only, read further..

Cause: POS Power Supply

I originally thought there was a ground isolation issue with the barrel of the plug end (which is NEG-) contacting the metal accessories grill. (I still do, but another story.)

This metal accessories grill (the metal tab with all the ports for sd, hdmi, 2 screws, etc.) is connected (and grounded to) the long metal band that wraps around the tablet, which in turn, is grounded to the rest of the device. That's good.

Theory: Unfiltered EMI from the PS, even attenuated TI from the power cord itself (its an antenna too!) ground itself on the common (and balanced) ground of the tablet. This creates a very noisy electrical field that the IPS screen can not handle (its out of spec, because its a cube design flaw). That's bad.

What I did:
I originally thought by removing the metal grill and isolating the ground that this would fix the problem. Well it didn't, so back to drawing board, and time for another cocktail.

Time to look at the PS. I opened it up and well it was as expected. A cheap, badly soldered, linear power supply with a under performing transformer. VNom was 12.20 volts, during load (charging) -- 10.4 volts. It gets worse (ok non-techies - 10.4 is not that great), after about a few min, I hear a click from the PS board, and look -- wow 3.2 volts -- under charge.

I found a PS from a portable HD which was a 12V 3A. Cut the old cord off, attach old cord to new PS, and plug in and test. ALL PROBLEMS GONE. The new PS is holding 11.89V with load.. fantastic. I even put the grill back on, and still NO PROBLEMS. Warning: I do still think there is a design flaw with the power port hole being too small.. they (cube) needs to drill that hole LARGER so there is no secondary contact. Its a design flaw -- listening CUBE?

Please, I am only throwing this out there for the community to digest, and comment. My comments are without warranty, are without prejudice, and the views expressed are not endorsed by Cube. (sorry, I have to say it.)

View attachment 6140

 

[edcox1234]

My cube u30gt was good..that is i could charge and type at the same time! Now, several charges later, its buggy durning charge. Also i've observed that, if i haved a very low battery level, i can put the charger on without the buggy effect..but in a very short while it'll return the bugginess. hmm. Love the tablet otherwise. thx. ed

 

[Danbbking]

My cube u30gt was good..that is i could charge and type at the same time! Now, several charges later, its buggy durning charge. Also i've observed that, if i haved a very low battery level, i can put the charger on without the buggy effect..but in a very short while it'll return the bugginess. hmm. Love the tablet otherwise. thx. ed

Hi
I've had the jumpy screen whilst plugged in charging issue with my U30GT-H and it has disappeared now I've just upgraded to the latest Cube firmware (1.05) released last week.

Also the keyboard (plugged in and unplugged) now is the most responsive I've had it, not dropping characters every now and then anymore!

cheers

D

 

[cokesippa]

Today I stumbled onto a possible solution. While its charging, connect to a computer via usb. Jumpiness is gone. I'm running 1.03 ics. Please try for yourself and report your results.