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Stelex · Jun 11, 2006, 09:56 PM

I noticed lately something rather strange with my MBP. As far as I can recall it happens only while charging or short while after the battery has been charged, but not exactly sure - I will have to pay more attention to when exactly this occurs.

When I touch the computer it feels OK, but when I slide my fingers over it, usually palm rest area, it feels very strange, like there is some voltage on the surface, or some invisible rubberish layer on the computer surface. Very difficult to explain, almost like the computer is trying to distance itself from the touch with some electric shield.

Anyone noticed something like this ?

Kadman · Jun 11, 2006, 10:02 PM

That's the new iDeflector Shields.

Seriously, it's possible that maybe you are feeling the vibrations of the hard disk?

rjt1000 · Jun 11, 2006, 10:26 PM

Hi,

I have had the issue you noted when using my 12 inch PB G4 1.33 in the third world where the electric supply is often not properly grounded. When running my finger lightly over the metal case adjacent to the track pad, there is a vibratory sensation which I believe to be electric discharge with my hand as the ground.

You may want to check the ground on the electric outlet you are using.

Best wishes,

rjt1000

Nai no Kami · Jun 12, 2006, 12:54 AM

Originally Posted by rjt1000

Hi,

I have had the issue you noted when using my 12 inch PB G4 1.33 in the third world where the electric supply is often not properly grounded. When running my finger lightly over the metal case adjacent to the track pad, there is a vibratory sensation which I believe to be electric discharge with my hand as the ground.

You may want to check the ground on the electric outlet you are using.

Best wishes,

rjt1000

That's exactly it. I live in the Third World, hence I experience that feeling. It's a grounding problem.

jettle250 · Jun 12, 2006, 10:07 AM

Yep, I had the same problem when using the plug adapter that sits right 'unto' the Power brick. I got rid of the problem by using the extension cable that comes with the MBP - why this fixes the problem, I don't know (more resistance?!?) but it has certainly done the trick for me.

MARINEOSX · Jun 12, 2006, 12:22 PM

I get this same thing no matter what. even if the battery is out and the power is unplugged. I had this same thing with the 15" PB and the 17" PB that I have now.

ibook_steve · Jun 12, 2006, 01:50 PM

Originally Posted by imjohnston

Yep, I had the same problem when using the plug adapter that sits right 'unto' the Power brick. I got rid of the problem by using the extension cable that comes with the MBP - why this fixes the problem, I don't know (more resistance?!?) but it has certainly done the trick for me.

The cable includes the third prong for grounding. That better grounds the computer, preventing the chance of current running through the chassis, which is what you feel sometimes on the case.

Steve

slugslugslug · Jun 12, 2006, 03:00 PM

Don't discount the possibility that you're in love with your MacBook Pro.

Sorry, someone had to go there.

sally · Jun 12, 2006, 03:27 PM

I have had that issue with an HP dv1040us. I agree with the rest that its not properly grounded. Since the HP is plastic I felt it on the speaker grills where the metal conducts.

Socially Awkward Solo · Jun 12, 2006, 04:00 PM

It sounds like you are getting a mild charge. Sorta like a tiny tingly, vibration feeling right?

At any rate plug it into another outlet, if you still get it take it to Apple ASAP.

cool1 · Jun 12, 2006, 05:37 PM

Originally Posted by slugslugslug

Don't discount the possibility that you're in love with your MacBook Pro.

Sorry, someone had to go there.

It is ok to love your MacBook Pro... Just don't LOVE your MBP!

jettle250 · Jun 13, 2006, 01:00 PM

Quote:
Originally Posted by imjohnston
Yep, I had the same problem when using the plug adapter that sits right 'unto' the Power brick. I got rid of the problem by using the extension cable that comes with the MBP - why this fixes the problem, I don't know (more resistance?!?) but it has certainly done the trick for me.

The cable includes the third prong for grounding. That better grounds the computer, preventing the chance of current running through the chassis, which is what you feel sometimes on the case.

Steve

But the plug I was using before (without extension into Power brick) was a 3-prong plug as well, so I haven't actually changed the type of plug that i'm using at all - merely the length of cable connecting the plug to the power brick... very strange!

ibook_steve · Jun 13, 2006, 01:38 PM

Originally Posted by imjohnston

But the plug I was using before (without extension into Power brick) was a 3-prong plug as well, so I haven't actually changed the type of plug that i'm using at all - merely the length of cable connecting the plug to the power brick... very strange!

Huh? There's only two ways to connect a Powerbook AC adaptor: the "duck head" two-prong connector that flips out or the 3 prong long cable. I don't know what you are talking about here.

Steve

n8236 · Jun 14, 2006, 09:21 PM

DUDE! Ya, me2! It's happened to me a couple times, it's like some invisible form of static/floating/magnet field that's covered over the areas left and right of the trackpad. It's phucking weird, i hope it's not a problem.

Spliffdaddy · Jun 14, 2006, 09:31 PM

Try flipping the plug around where it plugs into the wall (cords with 2-prong plugs only). See if it makes any difference. AC outlets are polarized - and sometimes it does make a difference which way the device is plugged-in.

analogika · Jun 15, 2006, 11:43 AM

Flipping the plug won't help in this case.

This issue has been covered tons of times since the titanium powerbook came out, most recently about two weeks ago:

MacBook Pro electric shock

Synopsis:

What you're feeling is AC current, and it's normal (according to Apple).

To avoid it, use the three-prong (i.e. grounded) power extension cord instead of the two-prong "duck bill" cornerpiece on the power supply.

The end.

bloodline · Jun 16, 2006, 05:18 PM

The "Bubbling Effect" you can feel when you lightly bush the MacBook Pro (and powerbook) surface is due to an ungrounded power supply.

Only the long plug wire (not the plug that slots into the PSU brick) provides a ground... I don't know why.

The sensation will go away when the MacBook Pro's power supply is properly grounded.

analogika · Jun 16, 2006, 06:10 PM

The third prong is what does the grounding.

Simon · Jun 17, 2006, 02:20 AM

Does anybody know why the plug isn't grounded and you need to use the cable to be grounded? I mean, why can't the plug just have a ground pin like most almost any other gadget I have with metal surfaces?

analogika · Jun 18, 2006, 06:09 AM

Because there's an awful lot of sockets that only offer two prongs.

Simon · Jun 18, 2006, 07:49 AM

Originally Posted by analogika

Because there's an awful lot of sockets that only offer two prongs.

That could well be Apple's reasoning, but still, it's not very smart. Having two prong sockets is a bad thing®. Basically all sockets should be grounded because every device that has a conducting (metal) case needs to be grounded. A MBP is such a device. The only thing that doesn't make it downright hazardous is the fact that we're not talking about 110/230V AC, but 18.5V DC.

analogika · Jun 18, 2006, 09:41 AM

Requiring a three-prong outlet for a wall-wart power supply GREATLY affects its usefulness when travelling.

I have never seen a three-prong wall wart.

And I have eleven of them in direct view from where I'm sitting, not counting the Powerbook adapter.

Simon · Jun 18, 2006, 11:23 AM

When I travel I normally carry an adapter with me. Apart from adapting between different socket/plug types, it also allows me to plug grounded devices into non-grounded sockets. That may be useful, but it's not necessarily safe.

The fact that so many are experiencing problems or discomfort when using the two prong ungrounded plug should give Apple second thoughts about offering ungrounded charging at all. Judging by how often the topic is brought up, I'm wondering by how much it increases Apple's support/warranty costs.