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Sony Recalls 18,000 VAIO Laptops
STFS writes "Reuters has a story about Sony having to recall 18 thousand VAIO laptops because apparently there is some risk of users receiving a small electric shock "if you have connected your PC (laptop) to external power, you have disabled your phone line, (while) simultaneously being connected to a grounded peripheral, and you are touching a metal part of the PC, and your phone rings"!" I can't begin to count the number of times that happens ;)
You can get the same effect without a computer. Just hold the end of a phone line with one hand and anything metal and gounded with the other and have somebdy call you. If anything this is a defect with the phone system, not the freaking computer!
This is because the phone company sends a 60-volt (if I remember correctly) pulse down the line to cause a ring...a leftover from the days when it they had to send enough energy to drive the electomechanical bell.
From the article... "There had been no injuries, McEvoy said, and fewer than 10 complaints had been received."
KARMA TAG! You're it.
as a former vaio laptop owner.. I will never buy a Sony product again. Dead after 15 months and extortionist prices from Sony to replace the bad motherboard. Was cheaper not only to buy new, but better laptop as well. Its amazing how much a company can turn you off to their products - not so much because something broke - but by their failure to offer any reasonable resolution. After all, we're not talking $50 calculators. While this recall is a step in the right direction I really wonder if it just caused an *internal* short, instead of perhaps 'shocking' the user, would they even bother.
The story is reprinted at CNN here. The description of what you have to do to get shocked alone is worth the read.
The cancel button is your friend. Do not hesitate to use it.
Umm. I think they mean that the user disabled the phone line functionality in the Vaio, meaning the computer doesn't respond when someone calls that phone line.
Here's how I interpeted it. Your laptop environment meets the previously outlined criteria. Someone calls your phone, which can be thought of as a small electrical current being sent to your phone. Because the the phone line is disabled on the Vaio and Sony didn't design the system correctly, the electrical current from the phone travels into the laptop hardware, the metal frame I guess. The computer is grounded, and you are touching some metal part of the laptop (read conductor). Therefore, the electrical current is passed into you, resulting into a minor shock.
I am certainly not an EE, but that makes sense to me.
As if the story were not unlikely enough...
It's my understanding that electricity doesn't work that way. Electricity needs to find ground; it will not shock you if it cannot. You can touch live wires so long as you are, say, wearing rubber boots and not in any way touching the ground. Standing barefoot on a damp basement floor, however...
So if the electricity is going down the chain to the dog (which it likely would not, since that's not the path of least resistance to the ground), the dog could only get shocked if the path was open. While urine would perhaps make this path more conducive (I can't honestly say I've stood in pee and shocked myself), it's higly unlikely any urination would be forced in the first place. Ergo, a path of lesser resistance would probably not be created.
So, in other words, it's humorous to those that know no better, but it sounds impossible to me.
(I am not an electrician, so someone here is perhaps more qualified to comment/correct me on this.)
Every once in a while I like to masturbate a new word into my vocabulary, even if I don't know what it means.
A large electric shock across my hand (ie both contacts on my hand) may cause temporary numbness and some pain, but quite probably no lasting damage.
I've had one of these, both contacts on fingers on one hand. While there was no lasting damage, I wouldn't catagorize the pain as "some pain." More like incredible pain in my whole arm lasting for hours followed by a day of numbness.
I've also caught one of those ring tones through my body. Sharp pain, but it only while the current was flowing. It was a very different type of pain, the large current through my hand didn't hurt while I was being electrocuted, but hurt a lot afterward, the ringtone "shocked" me but didn't hurt afterward at all.
The key part is that you can get a shock when the phone rings. Very bad. That means the user is exposed to a low impedance connection to the phone line, which is illegal (FCC part 68). Sure, to feel the shock you need to have a return path to earth ground... and the circumstances spelled out make it seem highly improbably.
But consider that those 2 wires from the phone line are supposed to be galvanically isolated, via a transformer, optocoupler, high-voltage low-value capacitors, or some other safe barrier. Consumers are never supposed to be exposed to those bare telephone wires, which run on telephone poles with high voltage power lines overhead.
Sure, the 50 to 100 volt ring signal can give you a bit of a shock. But the real danger is that those telephone lines are not safe if there is a failure like a tree falls onto the lines or they're hit by lightning. That's why all telephones are required by the FCC to isolate those wires from the user.
The FCC also has strict requirements that all telephone equipment fail as an open circuit (equivilant to not taking the phone off the hook), even if the lines are hit with extreemly high voltage such as 12,000 volt power lines coming into contact with the phone line momentarily.
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