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A comment on Logitech MX Master 3 vs. 2S Teardown. Parent comment

Re:Logitech MX Master 3 vs. 2S Teardown by jandrese on Tuesday December 17, 2019 @01:28PM (#21816829)
The power density on WiFi is minuscule. FCC Regulations mean you can transmit at a max of 300mW only, and the power you receive is affected by the Inverse Square Law on top of that, so total delivered power to your device is fractions of a mW unless your wireless router is right next to the router. Even then the entire process tends to be rather inefficient on top of that so the math probably doesn't work out.

The Qi mousepad makes a lot more sense.

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Re:Logitech MX Master 3 vs. 2S Teardown by hinkley on Tuesday December 17, 2019 @06:50PM (#21820351)
> FCC Regulations mean you can transmit at a max of 300mW only

Is that new? When I was originally playing with dd-wrt I was under the impression that 100 was the limit, discovered my AP was defaulting to something like 70mW, and would allow you to go higher.

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Re:Logitech MX Master 3 vs. 2S Teardown by jandrese on Wednesday December 18, 2019 @11:05AM (#21826211)
You might be right. My memory is from several years ago when I was working with some possibly dubious long range outdoor radios.
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Re:Logitech MX Master 3 vs. 2S Teardown by hinkley on Wednesday December 18, 2019 @01:32PM (#21827757)
The funny thing is that they don't seem to care about the directionality of the signal. You fire 120mW in a sphere and they have opinions. Narrow 100mW down to a (double) cone or a disc? No problemo.

Makes no goddamned sense to me.

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Re:Logitech MX Master 3 vs. 2S Teardown by jagger27 on Tuesday December 17, 2019 @04:56PM (#21819362)
Well a mouse is likely next to a couple of client devices (phone, laptop, smart watch) that each have their own radio. Maybe it adds up?
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Re:Logitech MX Master 3 vs. 2S Teardown by brokenmachine on Tuesday December 17, 2019 @06:02PM (#21819922)
It doesn't. The transmit time is packet switched between devices.
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