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joe sixpack
March 11th, 2005, 07:33 AM
The other day i had someone ask me about ESD they are just starting
to mess around with the inside of there computer and they had bought
a Anti-Static wrist band. They asked me if it was really needed i told them
i stoped using them because for what ever reason i've never really had any
problems (that i know of) and they are a real pain in the butt to wear.

This person asking me had got me thinking again about ESD.
Now we have all read the warnings im sure and they say that as little
as 80volts could fry a chip and you can only feel discharges above 3000.

Of course i've never noticed or had any problem with not using a wrist strap.
Im taking apart, handling, or building something electronic about every other
day All without a band on. Yet i almost never have parts fail on me.
Most of my hardware shares my bedroom i have stacks of mother boards
on my dresser, a pile of harddrives in the corner, and a handfulls of cpu's & memory
litter my desk. yet i have never had a part fail on me out side of harddrives.

Am i just very very very lucky or is this whole ESD thang a bunch of hype.
I mean i understand the warning but should'nt it have bit me on the ass in 7 years?

So i ask you hows your luck been? Let here the horror stories, If there are any!

barryp
March 11th, 2005, 01:59 PM
The other dayI had someone ask me about ESD

ISTR that people can be electrocuted by as little as 30 volts.

I take only the 'normal' precaution of touching the frame first and don't know that I've ever fried anything but you never know.

Exluddite
March 11th, 2005, 05:47 PM
It depends what you're noodling around with. ESD can trash certain components. Something else to consider is what kind of components you are dealing with. A decent sized capacitor, even if the system hasn't be on for a while, could hold enough of a charge to stop your heart. I'm not sure if a wrist strap would prevent this (by grounding via the wrist and not your torso) but I deal with that accordingly.Usually I gap the capacitors with a screwdriver.

joe sixpack
March 11th, 2005, 07:30 PM
The other dayI had someone ask me about ESD

ISTR that people can be electrocuted by as little as 30 volts.

I take only the 'normal' precaution of touching the frame first and don't know that I've ever fried anything but you never know.
it's the amps you have to worry about stun guns (taser) put out tens of thousands of volts
they can stun you with that many volts because the ampre is very low

im pretty sure someone told me your skin will resist at least 40 volts


It depends what you're noodling around with. ESD can trash certain components. Something else to consider is what kind of components you are dealing with. A decent sized capacitor, even if the system hasn't be on for a while, could hold enough of a charge to stop your heart. I'm not sure if a wrist strap would prevent this (by grounding via the wrist and not your torso) but I deal with that accordingly.Usually I gap the capacitors with a screwdriver.
ah ya i know about capacitors and the ole discharge trick but depending
on the capacitor size can still be dangerous.
my friends dad had this capcitor about the size of a can of hair spray. he discharged it once
and it sounded like a gun going off with a big ass spark.
of course you really never have to worry about that unless it's a monitor
or a powersupply i learned the hardway. i just leave the thing off for 12+
hours by then they should be discharged, i almost never bother trying to fix
a monitor. They are dangerous and i hardly know what im doing, unless its something simple.
Besides most times not worth the parts to fix them anyway.

Anyway of course i understand the warning about ESD however over stated it might be.
That's why i'd like to compare exp. and see if anyone has had a real case.

Terry Yager
March 11th, 2005, 07:52 PM
I don't believe I've ever fried anything that way, but I have heard from others who claim that they have. I wonder if that counts as a Friend-Of-A-Friend (FOAF) story?

--T

Rolf
March 12th, 2005, 04:52 AM
Bought one 8years, 8months & 8days ago.
Stopped using one 8y 8m & 7days ago. Like u said Joe, they're a HASSLE
**************
Sometimes I remember to touch the P/S first. Sometimes not.
In the past 2 weeks I have touched my 5150's Cards, CPU, Motherboard at least 200 times. Everything still works!
This in a place where today's temp is 34 Celsius or 93 Farenheit and Humidity virtually zero.

mbbrutman
March 12th, 2005, 08:45 AM
If you are not using a static strap and properly grounding yourself when you touch your electronic equipment, you risk zapping it. End of story.

The damage doesn't necessarily show up as a dead component with burn marks and carbon tracks on it. It could be (and most likely is) much more subtle, like occasional flakey operation, dropped bits, etc.

I like my machines reliable. I don't want to diagnose ghosts. I always wear a static strap when touching static sensitive parts, including hard drives with exposed ICs. It's a cheap precaution, and it's grounded in good industrial practices.

I work for a large compute company (hint, the initials are IBM). We go so far as to even properly ground the machine room floors and wear special shoes that dissipate static. If I go near the machines, the shoes must be on. (I'm a programmer by the way, so I rarely touch hardware now. But still, it's a requirement. Engineers are much more uptight about it, and rightfully so.)

joe sixpack
March 12th, 2005, 12:08 PM
If you are not using a static strap and properly grounding yourself when you touch your electronic equipment, you risk zapping it. End of story.

The damage doesn't necessarily show up as a dead component with burn marks and carbon tracks on it. It could be (and most likely is) much more subtle, like occasional flakey operation, dropped bits, etc.

I like my machines reliable. I don't want to diagnose ghosts. I always wear a static strap when touching static sensitive parts, including hard drives with exposed ICs. It's a cheap precaution, and it's grounded in good industrial practices.

I work for a large compute company (hint, the initials are IBM). We go so far as to even properly ground the machine room floors and wear special shoes that dissipate static. If I go near the machines, the shoes must be on. (I'm a programmer by the way, so I rarely touch hardware now. But still, it's a requirement. Engineers are much more uptight about it, and rightfully so.)
hmm intresting, i never knew ibm did all that. Of course there desktops
are crap but i really love my thinkpad's. I wonder what will happen now
that they've sold that department to the chinese.

mbbrutman
March 12th, 2005, 03:21 PM
Yeah, I wasn't too pleased with the NetVista desktops. One batch had bad capacitors on them which worked for about 18 months and then died. Looked like a power problem, but it was the motherboard.

On the other hand, that was one bad batch. Most of our desktops truck on for years. Maybe not the greatest value for a home consumer, but servicable for business, and they don't change the designs too often. (That's a good thing - you want interchangeable parts.)

As for Lenovo ('The Chinese'), IBM selling the PC division to them is just a recognition of the fact that most of the parts and most of the design comes from China. When was the last mouse, keyboard, printer, CD-ROM, etc. that you saw made in the US? This is true for Dell, HP, and other major brands too.

I wouldn't want to be Dell or HP now. It's a race to the bottom.

joe sixpack
March 12th, 2005, 04:12 PM
i did'nt mean "crap" as in unreliable, they played by there own rules
but so does dell, compaq and the such most times the cases are made
to look good not to be upgradable. dell use to love nonstandard atx connectors.
and i've seen some boards with solidered on cpu's BLAH!
I just put together my own it cost a little more but you get a lot more flexable.
Thank god the only time i have to worry about prebuilt systems is if i got
it 2nd hand & cheap as hell.

as for ibm well ibm is an american icon and even if most of the part
come from japan, (i dont remember seeing much from mainland china)
it's kind of like they sold of a part of america. what if ford sold out to say kia?

Thinkpads are well built and i love them, a bit over priced maybe.
Even if the parts are not made in america the profit still went to an american company.
I read that the thinkpads will be branded IBM for the next 5 years.
I dont know about you but im far from rich. Unless i see the quality at or above
what it is now i very much doubt i will put down 2000+ dollars for a new system.

about the floor at IBM ya that would be nice because you could just wear
boots rather then a band that gets in the way all the time, i would'nt mind that.

Terry Yager
March 12th, 2005, 04:22 PM
I have to agree that ThinkPads are the best line of laptops ever made. Speaking of odd-ball manufacturing locations, I just this morning noticed a small sticker on the back of my (old) Toshiba Tablet PC -- Made in Vietnam! Does that mean they are finally comming out of the Stone Age that we carpet-bombed them into?

--T

mbbrutman
March 12th, 2005, 04:46 PM
Actually, 'crap' is a good description. A lot of this stuff is barely reliable. Really, if a good lunch costs $12 to $15 US then why would you trust your data to a $30 to $40 CD-ROM? Scary.

(Quality components are getting hard to find ...)

I've used two IBM Thinkpads extensively. My T21 is over four years old now, and it's been a pretty good machine. Laptops, no matter how good they are, chew up hard drives. The backlight is getting weak, but that comes with the technology. My original T30 had a defect with the memory sockets. Except for software problems with the wireless Cisco Ethernet, it's been a good machine too. I used to travel quite a bit with the T21 and it's amazing how well it has held up.

Part of the problem with the IBM PC business was the profit - there was almost none. IBM management decided to cut and run - there are better places to deploy people and money. Which leaves HP, Dell, etc. in a race to the bottom.

Even with the ESD floor and shoes, it's still a good idea to wear a strap. I don't think people are this careful around their office PCs, but around the better equipment this is standard procedure. (After a few years most people get sloppy with the office PC, which has a depreciated value of about $1.)