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Bypassing regulatory locks, hacking AirPods and Faraday cages

lagrangepoint.substack.com

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Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#101

Post by jrockway »

> Since WiFi and a microwave operate at the same frequency (2.4GHz), we ran our leaky microwave at full power to block out any persistent network signals in the air.

Incidentally, WiFi tries to intentionally avoid this interference. Microwaves output no power during the zero crossing of the AC line that's driving it, and in this interval, there is no signal in the air to jam things. WiFi listens before sending (so as to avoid stepping on other stations), and the microwave's signal is enough to trigger this. (I forget if microwave ovens are "half wave" and you get 1/120th of a second 60 times a second, or if there is just a threshold near the zero crossing where there isn't enough power to interfere.)

I would say it's likely that the microwave oven didn't really do much here.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#102

Post by eru »

JumpCrisscross wrote: post #76
hoistbypetard wrote: post #75

Earlier quoted context omitted.

Thanks for posting this. I recognized the currency symbol but was confused by the "L".

The Indian numbering system marks odd power of ten, i.e. 10 ^ {1, 3, 5, 7}. Unit, thousand, lakh, crore [1]. Ours, on the other hand, does it mod 3, e.g. 10 ^ {1, 3, 6, 9}. Thousands, millions, billions, et cetera . [1] https://en.m.wikipedia.org/wiki/Indian_numbering_system

> Ours, on the other hand, does it mod 3, e.g. 10 ^ {1, 3, 6, 9}. Thousands, millions, billions, et cetera.

To make matters more confusing, for American English it goes millions, billions, trillions. For British English it used to go millions, milliards, billions, billiards, trillions, trilliards. (That 'long scale' is still the way German used to work ten years ago. No clue if it changed in the meantime.)

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#103

Post by grahamj »

userbinator wrote: post #54

It appears that the Hearing Aid feature is actually an equalizer preset that is pushed to the AirPods and will replace your transparency mode. Apple could've just not marketed these as "hearing aids" or used the medical terminology, as every other TWS with parametric EQ and transparency mode can do the same thing, and they wouldn't have the regulatory hawks going after them. They only lose the marketing edge, but per…

> every other TWS with parametric EQ and transparency mode can do the same thing,

AirPods too! I'm am yet to be convinced that this is any different than using a different hearing test app like Mimi and applying the resulting audiogram, as has been possible for years.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#104

Post by lathiat »

_rs wrote: post #97
ilt wrote: post #91

Earlier quoted context omitted.

I live in India and I have been using hearing aid feature since at least March when I bought Airpods Pro. Only that it wasn’t called as such earlier. It uses the audiogram I had provided it which it used to create a customized equalizer for my hearing disability. I am sure they must have improved upon the capability in new OS versions but functionally it has been present for a while now.

I suppose the difference is 1st party support for creating the audiogram, plus the clearance from the US gov to market it the way they want as OTC hearing aids

It also applied the same profile to both ears, which matters for some. My hearing loss is highly asymmetric.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#105

Post by andreareina »

eru wrote: post #102
JumpCrisscross wrote: post #76

Earlier quoted context omitted.

The Indian numbering system marks odd power of ten, i.e. 10 ^ {1, 3, 5, 7}. Unit, thousand, lakh, crore [1]. Ours, on the other hand, does it mod 3, e.g. 10 ^ {1, 3, 6, 9}. Thousands, millions, billions, et cetera . [1] https://en.m.wikipedia.org/wiki/Indian_numbering_system

> Ours, on the other hand, does it mod 3, e.g. 10 ^ {1, 3, 6, 9}. Thousands, millions, billions, et cetera. To make matters more confusing, for American English it goes millions, billions, trillions. For British English it used to go millions, milliards, billions, billiards, trillions, trilliards. (That 'long scale' is still the way German used to work ten years ago. No clue if it changed in the meantime.)

I still mourn the long scale. A billion is obviously a million millions.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#106

Post by subarctic »

jrockway wrote: post #101

> Since WiFi and a microwave operate at the same frequency (2.4GHz), we ran our leaky microwave at full power to block out any persistent network signals in the air. Incidentally, WiFi tries to intentionally avoid this interference. Microwaves output no power during the zero crossing of the AC line that's driving it, and in this interval, there is no signal in the air to jam things. WiFi listens before sending (so as…

Whatever the theoretical analysis tells you, I've been able to reproduce a microwave interfering with a wifi signal with at least one microwave and router. I've had other times where it didn't have a noticeable effect though.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#108

Post by rollulus »

jrockway wrote: post #101

> Since WiFi and a microwave operate at the same frequency (2.4GHz), we ran our leaky microwave at full power to block out any persistent network signals in the air. Incidentally, WiFi tries to intentionally avoid this interference. Microwaves output no power during the zero crossing of the AC line that's driving it, and in this interval, there is no signal in the air to jam things. WiFi listens before sending (so as…

> Microwaves output no power during the zero crossing of the AC line Why is this? Do microwaves by design modulate their 2.4gHz on top of 50/60Hz?

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#109

Post by SushiHippie »

andreareina wrote: post #105
eru wrote: post #102

Earlier quoted context omitted.

> Ours, on the other hand, does it mod 3, e.g. 10 ^ {1, 3, 6, 9}. Thousands, millions, billions, et cetera. To make matters more confusing, for American English it goes millions, billions, trillions. For British English it used to go millions, milliards, billions, billiards, trillions, trilliards. (That 'long scale' is still the way German used to work ten years ago. No clue if it changed in the meantime.)

I still mourn the long scale. A billion is obviously a million millions.

Thanks! In germany we use the long scale, and this is the first time it clicks.

"Eine Billion" is Million² bi -> 2 "Eine Billiarde" is 1000 * Million² "Eine Trillion" is million³ tri -> 3 "Eine Trilliarde" is 1000 * Million³ And so on

Yes I knew what a million, milliard, billion, billiarde and so on are, but it never made click that the long scale makes so much sense.

Re: Bypassing regulatory locks, hacking AirPods and Faraday cages

#110

Post by RF_Savage »

rollulus wrote: post #108
jrockway wrote: post #101

> Since WiFi and a microwave operate at the same frequency (2.4GHz), we ran our leaky microwave at full power to block out any persistent network signals in the air. Incidentally, WiFi tries to intentionally avoid this interference. Microwaves output no power during the zero crossing of the AC line that's driving it, and in this interval, there is no signal in the air to jam things. WiFi listens before sending (so as…

> Microwaves output no power during the zero crossing of the AC line Why is this? Do microwaves by design modulate their 2.4gHz on top of 50/60Hz?

The magnetron needs about -4.4kV to work and food does not care about the purity of the signal, only net energy delivered.

So the transformer based microwave oven power supplies have a 2.2kV transformer and then double that to 4.4kV for the magnetron.

There is no filtering or smoothing, as those parts would cost money and present a danger to the service technician.

So the voltage feeding the magnetron is not even sinusoidal.

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