Power related touchpad woes continue...

[arbarnhart]

I may be sending it back for warranty service (more likely replacement). Last night, I connected it to a powered USB hub and got the behavior I have seen a couple of times from having the wall charger on a car inverter. The touchpad starts registering incorrectly. In portrait mode, trying to use a soft keyboard it will get extra characters that are usually on the same row. It was practically unusable right after it happened, but by this morning it was almost normal again (was still getting a few extra, but not as bad as before). I suspect that tonight it will probably be okay again. The input technology is "capacitive" which likely means there are capacitors involved; the only explanation I can think of for it stabilizing with time is a capacitor slowly dropping voltage after a spike.

Am I the only one that has seen this issue? I did some Googling and found this is a known issue with some noteboook touchpads, which are also capacitive.

Assuming it returns to normal, I may just have to accept that it can only be charged by clean wall power using the provided charger or from a computer (I have done that without trouble). But I am not sure; mine might be an anomaly. I would hate to go the trouble of trying to get warranty service only to find they all do this. I am not even sure how much luck I would have with service if the problem resolves itself in less time than it would take to get it to a service center. I will follow up later to verify whether or not it resolves again.

Other suggestion? I have looked at surge protectors that have USB outlets, but I don't know if that would help.

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[arbarnhart]

It has partially recovered - the touchpad works fine now when it is disconnected but still glitches, though not quite as badly, when charging (and I am using the supplied charger). I expect that tonight it will probably be back to normal. If it is, the question becomes whether all units do this or whether this is a bad unit. In an odd way, I almost hope it stays glitched while charging because then I would be able to get it replaced. Has anyone used an inverter (car 120V AC converter) with success to power the unit via the included wall charger? Anyone with an inverter eager to test? I didn't think so...

[arbarnhart]

I found this:
USB Surge Protector - B&B Electronics
but that is a bit steep. Looking for a more cpetitively priced model...

[arbarnhart]

A sampling of a few posts that I think are related for the curious. I would really appreciate it if someone with good working knowledge of this type of electronics weighs in. At present, it works fine off battery but the touch pad is difficult to use if it is charging; even from sources that used to be okay. Is there a simple way to disconnect the battery and let the internal components completely drain? My limited knowledge of capacitance makes me suspect something still needs to discharge. The good (sort of) news is that nearly everything I read reports usage problems that do clear up without permanent damage.

Power inverter freaks out my touchscreen
Loss of touchscreen function when charging from inverter in car
iPhone 4 Multi Touch Issues when Charging In a Car - MacRumors Forums
Laptop touchpad unusuable when on AC power (via inverter) in vehicle

[WasteLandSavage]

OK just food for thought.
I just ordered my A2109 yesterday.

BUT this problem may or may not be with your hardware and here's why.

I am typing this right now on my Iconia A500 running ICS, And when I hook a Bluetooth Keyboard to it it will type along just fine for awhile minutes, hours or days.
Then as you say it starts with a lot of phantom key presses wither I'm touching my keyboard or not.
Wither it's powered or on battery. Sometimes it will stick so bad that even after I shut off the keyboard it will keep going with a line that looks like this.

hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh hhhhhhhhhhhhhhhhhhhhhhhhhhhh

Here is a link to a thread I started about it It maybe of some help.

Bluetooth Keyboard Stutters on Iconia A500, Loses Connection?

I am typing this on a wired usb keyboard and at times as well for no apperant reason it's keys will either do a quick stutter or some maybe completely unusable until after I restart my tablet..

The research I've done says this is a well known problem with ICS itself.
And very few have found away around it pertaining to specific models wither it be phones or tablets.

I have no idea if your running ICS or JB?
But I hope it's not the same in JB or I'm in for a wild ride trying to get it to work on my bluetooth keyboard since I really will have no way of leaving my wired keyboard hooked up to it while at my desk.

Hope This Helps. Ricky

[arbarnhart]

I am running JB. My research indicates that using an AC2DC converter powered by a DC2AC inverter often causes problems with capacitive input devices. Typing with BT keyboard or using a USB mouse both work fine while it is having trouble. The real message is don't use an inverter in a car or you may put the tablet at risk. I am still hopeful that my problem will resolve itself. I am using a soft keyboard (SwiftKey Flo beta) now and it is working properly. But I am using battery power only. I charged with the tablet completely powered off last night.

[WasteLandSavage]

I am running JB. My research indicates that using an AC2DC converter powered by a DC2AC inverter often causes problems with capacitive input devices. Typing with BT keyboard or using a USB mouse both work fine while it is having trouble. The real message is don't use an inverter in a car or you may put the tablet at risk. I am still hopeful that my problem will resolve itself. I am using a soft keyboard (SwiftKey Flo beta) now and it is working properly. But I am using battery power only. I charged with the tablet completely powered off last night.

Well I have never had a reason to use a power converter in my car as most times I'm only using mine at home.
Now sometimes when we are out my wife will use her iconia a500 but we have never used it on a converter so I can't comment on what it would do.
Although you did ease my mind about the bluetooth usage on the A2109 not having the same troubles as my iconia has, for sure it won't if they both work fine while you are having this trouble.

Since you are using another virtual keyboard of sorts and it is not giving you any problems like the oem one is.
Maybe a Factory Reset would fix it?
It might just be possible that something in the programing got fouled up a bit when you tried using the converter in your car.
Although it shouldn't effect it, I would say it is possible since another softkey program is working without any problems.
I seriously doubt it's any of your hardware.

Let us know how it goes. Ricky

[arbarnhart]

When the touch is screwy, no soft keyboard works. In fact, one of the clearest illustrations of it (literally) is to open a drawing program and randomly poke the screen, which should result in a bunch of dots. When it has the problem, many of the dots will be horizontal (in landscape mode) lines. All programs system wide have trouble. If you check some of the links I posted earlier about completely different tablets and systems, it is all pretty much the same underneath. Capacitive touch is extremely power sensitive by its very nature. Capacitors hold a charge for quite some time, so once you get it screwy it can take a while to clear up.

[WasteLandSavage]

When the touch is screwy, no soft keyboard works. In fact, one of the clearest illustrations of it (literally) is to open a drawing program and randomly poke the screen, which should result in a bunch of dots. When it has the problem, many of the dots will be horizontal (in landscape mode) lines. All programs system wide have trouble. If you check some of the links I posted earlier about completely different tablets and systems, it is all pretty much the same underneath. Capacitive touch is extremely power sensitive by its very nature. Capacitors hold a charge for quite some time, so once you get it screwy it can take a while to clear up.

OK another wild idea.
I understand what your saying I misunderstood your previous post Sorry about that.

OK here's the idea sometimes on a laptop the circuits will get a static charge causing glitches system wide even to the point where they won't boot at all.
So to fix the problem you take out the battery and unhook the power supply, Hold the power button for 10 to 30 seconds.
Put the battery back in and reconnect the power and that clears it right up.
I haven't had that problem much but it has happened and that has always fixed it!

Now since you can't remove the battery, You may want to try running the tablet completely out of battery power where it shuts down itself.
Hold down your power button for 10 or so seconds then plug the power back up and try it and see if that fixes it.

I know tablets and laptops are different animals, but the principal is the same.
It's just dumb enough to work.

[arbarnhart]

Powering off, not just suspending, seemed to fix it. But it took a couple of nights. I am not going to use the inverter to power it ever again. I am planning to get one of those Trent USB battery packs for long trips.