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Check if your IKEA chair is compatible with your screen

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Re: Check if your IKEA chair is compatible with your screen

#121

Post by m463 »

yborg wrote: post #23

One of my first jobs 30+ years ago was ESD testing automotive and consumer electronics. I would spend a week with a discharge gun methodically running different discharge energies and waveforms both directly onto the devices as well as onto radiators at various distances from the device under test, as well as any cabling/harnessing that attached to the device. Then the design team would figure out the reason for any…

Reminds me of woz's apple video on ESD: https://youtu.be/hLOQ7zOWGAA

Personally I remember having a pickup truck with a velour seat. During winter I would slide off the seat at a gas station and the first thing I would tough would be the gas pump handle - ZAAAP. Not what you want at a gas station!

Re: Check if your IKEA chair is compatible with your screen

#122

Post by mlyle »

Eduard wrote: post #117
mlyle wrote: post #30

Earlier quoted context omitted.

Cars are a terrible ESD and EMC environment and safety critical at the same time. Computer equipment usually does pretty well, especially after installation (when there's good ground path everywhere and it's in a chassis). Between ferrite beads and TVS, there's a pretty good amount of protection, and I've seen pretty few ESD anomalies-- a reset or two when touching connectors long ago is about the extent of it. RFI a…

TVS == Transient-voltage-suppression diode? https://en.m.wikipedia.org/wiki/Transient-voltage-suppressio...

Yup, explicit TVS or just diodes doing clamping or whatever. There's a fair bit of protection circuitry around. Often there's series resistors which help a lot, too.

Not to mention that all modern CMOS chips have protection structures on the input (though not really as good as you'd like for something that is randomly handled by charged up humans).

Re: Check if your IKEA chair is compatible with your screen

#123

Post by bobsmooth »

andrewfromx wrote: post #110
kstrauser wrote: post #33

Earlier quoted context omitted.

This is the greatest thing I've read today. I love when software and the real world have entirely unexpected interactions. And by love, I usually mean hate, especially when I'm the one that has to debug them.

my favorite story on this is a town in north east usa changed it's traffic lights from energy wasting old fashion lights to new fancy low energy lights. The unexpected result: in winter time these lights did not melt the snow away and the lights were opaque with white snow.

Technology Connections did an episode on this kind of stuff. GE just installs heaters in their streetlights now.

Re: Check if your IKEA chair is compatible with your screen

#124

Post by m463 »

khazhoux wrote: post #25

Lately, I’ve become a fan of analog chairs. No Wi-Fi, no camera, no GPU. Besides the retro appeal, I actually find myself to be more creative!

Adding those to a chair are just an excuse to download more data about your sitting and fidgeting habits to sell you more stuff.

Re: Check if your IKEA chair is compatible with your screen

#125

Post by m463 »

SenHeng wrote: post #95

I recently bought Dell’s latest 32” monitor to connect to my 2018 Mac mini and I’ve noticed that the screen blacks out for a few seconds randomly. I did a bit of a search and there were a few mentions of static possibly being a culprit. Didn’t actually try to confirm it though and now I’ll never get the chance to because I’ve switched 1) desk placement, 2) desk, 3) Mac Studio. The problem has gone away. I don’t have…

that happens to my monitor too. Sometimes it happens exactly when I click on something and I wonder how that happens.

Re: Check if your IKEA chair is compatible with your screen

#127

Post by stephen_g »

fsckboy wrote: post #97

you should NOT ground your chair directly, only ground it through a large resistor, 100K or so. (you might want to check that value, it's from memory, I think you want any potential electric "shock" to be down below the 1 milliAmp range) I'd use a ground strap designed for wearing while you handle MOSFET ICs. if you ground your chair directly, it is likely to make YOU be the best circuit to ground when you handle you…

Very true, but the resistance should be even more - for safety it should be at least 1 megaohm.

Re: Check if your IKEA chair is compatible with your screen

#128

Post by eitland »

tinglymintyfrsh wrote: post #106
mlyle wrote: post #30

Earlier quoted context omitted.

Cars are a terrible ESD and EMC environment and safety critical at the same time. Computer equipment usually does pretty well, especially after installation (when there's good ground path everywhere and it's in a chassis). Between ferrite beads and TVS, there's a pretty good amount of protection, and I've seen pretty few ESD anomalies-- a reset or two when touching connectors long ago is about the extent of it. RFI a…

My dad's car had velour interior. Anytime the humidity was below 50%, expect the car to zap you and to be zapped touching door handles. I assume there are/were numerous gas station fuel fires from cars with velour upholstery.

One stupid little thing I realized after having sometimes been consistently zapped by mybcar door and other times not getting zapped in the same weather and humidity:

If I open the door and grasp for the (metal) edge of it before I start sliding out of my seat I will be grounded and consequently not build up charge as I leave the seat.

Re: Check if your IKEA chair is compatible with your screen

#129

Post by eastbound »

m463 wrote: post #121
yborg wrote: post #23

One of my first jobs 30+ years ago was ESD testing automotive and consumer electronics. I would spend a week with a discharge gun methodically running different discharge energies and waveforms both directly onto the devices as well as onto radiators at various distances from the device under test, as well as any cabling/harnessing that attached to the device. Then the design team would figure out the reason for any…

Reminds me of woz's apple video on ESD: https://youtu.be/hLOQ7zOWGAA Personally I remember having a pickup truck with a velour seat. During winter I would slide off the seat at a gas station and the first thing I would tough would be the gas pump handle - ZAAAP. Not what you want at a gas station!

That’s why in Europe the gas nozzle doesn’t have the little lock - It requires that you keep pressing it. So that you avoid going back to the car, charging static, coming back to the nozzle and having a spark.
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