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A certain laptop mfg. doesn't affix EMI shielding to the rear of their touchpads.

Many people see the issue exacerbated when they plug in the power adapter, but for me, the issue is pretty consistently intermittent, occurring every ten to forty minutes for around two minutes at a time.

Is there any possibility this could be related to a higher voltage draw from the battery, which might be correlated to some process that happens every now and again?

Is there any way I could simulate this to induce the EMI, and see if it correlates to a more consistent presentation of the touchpad issues?

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Basically, you'll be using the touchpad, and all of the sudden the same finger movement that would cause a edge to edge mouse movement, will only cause the cursor to move an inch, where you have to vigorously rub your finger on the touchpad to get the mouse to make its jumpy way to the other side. Do nothing for two seconds, and it'll be back to normal.

Happens especially during/after two finger scrolling, which is notorious for causing a spike in CPU usage (an issue Asus hasn't triaged since being reported 2014, still shipping the same drivers, same touchpad hardware in many of their new models), which could be correlated to the spike in current draw, correlatable to the issue being triggered by additional EMI.

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    I hope people here can appreciate your question a) what symptoms do you see when you get what you think is electromagnetic interference? b) you could try asking on electronics.stackexchange or physics.stackexchange i'd also suggest the chat feature there but stackexchange sites can need some rep for that. also c) arstechnica forum may have some people that know about this. – barlop Dec 11 '19 at 11:47
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    @John his concern isn't that the radiation would cause harm to a human.. I don't know what symptom he is experiencing ON HIS LAPTOP OR (or to some other device near it), but e.g. on airplanes it is a concern electronics.howstuffworks.com/question230.htm in terms of symptoms to the airplane also scientificamerican.com/article/experts-cell-phone-screeching – barlop Dec 11 '19 at 12:18
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    One problem is that EMI covers a very large variety of effects and problems. Without narrowing down what the actual effect is (which you don't state) it is difficult to suggest how you might replicate it or even what of the thousands of electronic devices around you might be causing it. EMI can induce current in all sorts of ways depending on the power, frequency and even source direction. What exactly are the symptoms of this interference? – Mokubai Dec 11 '19 at 12:28
  • Basically, you'll be using the touchpad, and all of the sudden the same finger movement that would cause a edge to edge mouse movement, will only cause the cursor to move an inch, where you have to vigorously rub your finger on the touchpad to get the mouse to make its jumpy way to the other side. Do nothing for two seconds, and it'll be back to normal. Happens especially during/after two finger scrolling, which is notorious for causing a spike in CPU usage, which could be correlated to the spike in current draw, correlatable to the issue being triggered by addition EMI. – Eric Lang Dec 11 '19 at 12:31
  • @EricLang As a different test, I wonder if you can add an EMI shield? – barlop Dec 13 '19 at 23:06

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