jdf@pbhyc.UUCP (Jack Fine) (02/22/88)
Static electricity would seem to be the problem although I don't know this for sure. Micro computer systems (IBM PC XT) from certain users will suddenly blank the screen and freeze up requiring a cold boot to get started again. We have tried various things such as static sprays, static dischargers, better grounding and so on but the problem seems to persist. It doesn't happen to everyone and not to all building locations. It seems to be happening in one or two very specific areas of the building and it comes on suddenly. A person sitting working never noticing a problem before will have a screen die and system lockup with data loss. Then it begins to repeat on the same person. Replacing systems and other pieces of hardware doesn't seem to help and as I have said the static solutions do not stop the problem. Someone sitting a couple of feet away doing the same things (apparantly) will not have a problem. Sometimes the problem goes away and we have attributed it to one of the things we have tried. I am beginning to wonder though if that is the case or the cause of the problem simply went away. Anyone else run into this kind of problem? Anyone find a viable solution to it? Thanks Jack
aburt@isis.UUCP (Andrew Burt) (02/22/88)
In article <959@pbhyc.UUCP> jdf@pbhyc.UUCP (Jack Fine) writes: >... Micro computer systems (IBM PC XT) from certain users will >suddenly blank the screen and freeze up requiring a cold boot to get >started again. We have tried various things... >It seems to be happening in one or two very specific areas of the building... >A person sitting working never noticing a problem >before will have a screen die and system lockup with data loss. Then it >begins to repeat on the same person... >Someone sitting a couple of feet away doing the same >things (apparantly) will not have a problem. Sometimes the problem goes >away and we have attributed it to one of the things we have tried.... >Anyone else run into this kind of problem? I have indeed seen this as a participant. In my case I have narrowed it down to fabric of clothes vs. fabric of chairs. It seems when I wear pants with any polyester content to them, and sit in a chair which has (I think) polyester in the cover -- the computer gets shocked when I stand up (including an audible pop). A different chair or pants fabric and there are no problems. (Carpet on the floor rubbing on shoes could cause this too.) If I take the same chair and put a cotton towel on it, no problem. This could explain why you find it happening to certain people, in certain locations, but not reliably. I've tried a few approaches such as touch pads, anti-static spray, all to no avail. I'm not about to plunk down the money for an anti-static chair mat and find it doesn't work either... What I have found to work, though, is this: Backing the chair up about five feet from the equipment, then standing up. Still pops, but nothing gets hurt. (I also tend to avoid certain clothes in my wardrobe...) -- Andrew Burt isis!aburt Fight Denver's pollution: Don't Breathe and Drive.
hes@ecsvax.UUCP (Henry Schaffer) (02/22/88)
and get them to change from nylon (or other synthetic) to cotton. Sometimes makes a big difference. --henry schaffer n c state univ
karl@ddsw1.UUCP (Karl Denninger) (02/23/88)
In article <959@pbhyc.UUCP> jdf@pbhyc.UUCP (Jack Fine) writes: > >Static electricity would seem to be the problem although I don't know this >for sure. Micro computer systems (IBM PC XT) from certain users will >suddenly blank the screen and freeze up requiring a cold boot to get >started again. We have tried various things such as static sprays, static >dischargers, better grounding and so on but the problem seems to persist. >It doesn't happen to everyone and not to all building locations. It seems >to be happening in one or two very specific areas of the building and it >comes on suddenly. A person sitting working never noticing a problem >before will have a screen die and system lockup with data loss. Then it >begins to repeat on the same person. Replacing systems and other pieces of >hardware doesn't seem to help and as I have said the static solutions do >not stop the problem. Someone sitting a couple of feet away doing the same >things (apparantly) will not have a problem. Sometimes the problem goes >away and we have attributed it to one of the things we have tried. I am >beginning to wonder though if that is the case or the cause of the problem >simply went away. Anyone else run into this kind of problem? Anyone find >a viable solution to it? Check out the power coming into the system unit itself. To do this cheaply (without renting a line analyzer; these tools do exist) you can move the CPU in question to a place where you know it is not on the same circuit. In fact, move it to a place where there is another, correctly functioning, CPU and plug in to that power. If the problem disappears, you have a really terrible power source on that PC.... the problem could be interferance in the RF band, spikes on the line, or nearly anything else that disturbs clean power distribution. The fix, in these cases, if you cannot move the equipment or power feed, is to buy a "line stabilizer" or a full-blown on-line UPS. Your garden-variety surge-suppressor will likely not help (although being as cheap as they are, it is worth a try). From your description (only in some areas of the building, and it comes and goes) I am lead to believe that you might have a problem with a noisy piece of electrical gear on the same branch circuit as your problem systems. If the offender can be found, you simply move it to another branch circuit or move the computers (if the offender cannot be moved). ---- Karl Denninger | Data: +1 312 566-8912 Macro Computer Solutions, Inc. | Voice: +1 312 566-8910 ...ihnp4!ddsw1!karl | "Quality solutions for work or play"
wheels@mks.UUCP (Gerry Wheeler) (02/24/88)
In article <2216@isis.UUCP>, aburt@isis.UUCP (Andrew Burt) writes: > In article <959@pbhyc.UUCP> jdf@pbhyc.UUCP (Jack Fine) writes: > >... Micro computer systems (IBM PC XT) from certain users will > >suddenly blank the screen and freeze up requiring a cold boot to get > >started again. We have tried various things... > >Anyone else run into this kind of problem? > > I have indeed seen this as a participant. In my case I have narrowed it > down to fabric of clothes vs. fabric of chairs. I'm not sure what is generating the static charge in my case, but once I'm charged up I can crash my computer by having my chair come in contact with the desk. I was thinking about connecting the chair to the desk with a strap so they're always at the same potential, but that would tie me down too much. Maybe I need a ground strap dragging on the floor from the bottom of the chair. (Hmmm, then I could add bumper stickers, and a cool sounding muffler. Maybe a turbo charger too.) -- Gerry Wheeler Phone: (519)884-2251 Mortice Kern Systems Inc. UUCP: uunet!watmath!mks!wheels 35 King St. North BIX: join mks Waterloo, Ontario N2J 2W9 CompuServe: 73260,1043