An odd effect I'd like explained

[Smilin]

First off I've stopped doing this as I suspect it will cost me some serious $$$ in fried hardware eventually.

The scenario:
1. PC, monitor and whatnot sitting on a wooden desk. Everything is hooked up to properly grounded outlets
2. Me sitting in a big comfy chair with my keyboard on my lap. I'm wearing shorts and the keyboard is touching my bare knees.
3. Next to me is on of those 'neon' special effects lamps. You know the globes with the neon inside and the slowly flowing 'Lightning' that follows your finger as you touch the glass. Mine's actually a couple of mushrooms instead of the globe but otherwise it's the same thing. The lamp is on a different circuit that may or may not have decent grounding.

If I put my whole hand on the lamp while I'm sitting in the scenario above after a few seconds my computer will beep. You know the standard ascii 007 or Ctrl-G type of beep. If I keep holding it, it will continue to beep every few seconds.

What gives? I'm thinking some sort of static buildup but I'm not sure of the details or how it's causing a beep of all things (why not just fry a chip or something?)

 

[Peacekeeper100]

Well lets see. You are creating a static charge from the globe. This static charge is then creating another static charge in the keyboard. This charge is then enough to induce a voltage equal to the input voltage of the computer. The problem comes from the fact that you are sending invalid data to the computer. You probably aren't creating enough of a current to fry the chips, but enough current and voltage to send an invalid input to the computer. I don't think the keyboard is as sensitive to static charge as the boards on the computer, but if you create enough of a charge you will fry something.

 

[Smilin]

I bet that's what it is. I was thinking I was somehow generating enough of a charge to actually power the speaker. The keyboard sending a junk code upstream is probably much more likely.

Thanks

 

[FoxHound23]

Actually, I have one of those globes two, just the plain round one. I've noticed the thing interfering with common household electronics as well. I had it sitting next to a 2.4 ghz cordless phone set and it caused the phone to start ringing on its own. I had it next to a different 2.4 ghz cordless phone base, and it caused the handset to lose contact with the base. Then I got curious and starting exposing other electronics to it, I put a Gameboy Advance near it, it caused the volume to increase in pitch and caused the game to lock up. They really ought to put some warning labels on those globes, they cause some really NASTY interferance. Possibly an FCC issue?

 

[Mark R]

These devices work by emitting radio-frequency energy from the 'antenna' in the centre. Essentially, they are crude radio transmitters, with enough power to ionise the low pressure gas inside the globe. If you increase the power of the transmitter, you don't need low pressure gas, it will discharge through the air - such a device is commonly known as a tesla coil: see http://www.geocities.com/rcopini/fullpower.html for an example of such a device.
By placing your hand on the glass, you provide a path for the current, and channel it through your body extremely close to the keyboard. Thereby exposing it, to intense EMI (electromagnetic interference), which as keyboards are usually not shielded, is picked up by the circuits, causing incorrect operation.

 

[Smilin]

"They really ought to put some warning labels on those globes"

They do. There's a printed warning in the box when you buy em that says to keep them at least 2 feet from electronics. Needless to say I don't put it near my computer...especially on the side with the plexiglass.

 

[zephyrprime]

Whenever I place my 2.4ghz phone next to my computer speakers and the phone is on, it will cause the speakers to make this tone. Those are my 2 cents.

 

[alkemyst]

I have always been waiting to hear of the attempted case mod of putting one of these inside

 

[ReiAyanami]

shocking :Q

 

[Ryanov]

Actually, it's an electromagnetic effect -- not an electrostatic effect. The only way it could be an electrostatic effect (or magnetostatic, which is clearly not the case) is if the keyboard you're touching is a good conductor, which it almost surely is not. It's similar to the combination of Faraday and Ampere's Laws for dynamic cases. It's probably mostly an induced voltage due to the field or a displacement current that is similar to that of a capacitor's.

 

[Kilazar]

Whoa lol, I was thinking of putting my plasma tube inside my case.. I have never had it near any electric device so never thought about the EMI aspect. lol Not sure if the plasma tube works off the same concept as the Globes with the lighting or not, but it does produce a similar effect inside the tube, except at a vastly slower pace (kinda like lightning in super slow motion, and in varying colors). Can anyone confirm if the plasma tube runs the same as the lighting globes?

 

[Descend492]

Originally posted by: Ryanov
Actually, it's an electromagnetic effect -- not an electrostatic effect. The only way it could be an electrostatic effect (or magnetostatic, which is clearly not the case) is if the keyboard you're touching is a good conductor, which it almost surely is not. It's similar to the combination of Faraday and Ampere's Laws for dynamic cases. It's probably mostly an induced voltage due to the field or a displacement current that is similar to that of a capacitor's.

???? electromagnetism arises when you have electrical currents flowing, which then generate a magnetic field. And a magnetic field doesn't arise unless you're moving an electrical charge against it (or a permanent magnet, which is essentially the same thing).

Also, this emitter creates a high enough voltage to ionize the (probably) vacuum in the glass ball, but does not put out enough current to harm a human. So, the current flows from the emitter through the glass, through you (it probably gets reduced somehow by the resistance of the glass or whatever the ball is so that it is absolutely harmless), and travels from your finger to ground. If you're standing in a puddle of water on the ground, it'll most likely go through you directly to your wet feet and into the ground (thereby "grounding" the signal). However, if you're in your new Adidas kicks, with a comfy rubber sole, you have a lot of resistance through you to ground (not to mention you might be on the second floor, on a large wooden floor). Therefore, the path through the keyboard, through the (conducting) cable to your computer, which is grounded with little resistance becomes quite appealing, and probably much less of a potential drop than through your body. Because the voltage is so high (it had to travel through gas, a fairly decent conductor), it probably has little problem jumping from your fingers to the keyboard.

The reason the globe affects nearby electronics is most likely electromagnetism. A voltage (/charge) that large can probably creates a decent magnetic field around it, which can have a significant effect on the minute voltages in your phone or processor.