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iPhone audio detectable with AM radio

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Re: iPhone audio detectable with AM radio

#51

Post by dgellow »

geerlingguy wrote: post #47

I just tested this on my iPhone XS with both an old AM radio and my SDR receiver, and neither seemed to cause any kind of signal or interference around the 930-980 KHz range. My dad, a radio engineer (who worked for one of the US' largest AM radio stations for a decade), also tested with his XR and couldn't find any signal. I'm wondering if either it is limited to the iPhone 7 and/or 8, or if the Twitter OP might hav…

What about https://twitter.com/mehdi0x61/status/1301094353050439681 ?

> I reproduced this on iPhone 6, 8 Plus and 11 Pro, using an H probe (only happens when playing through the speaker)

> In my tests, all the 3 phones broadcast on 857 KHZ (broadcast might not be the correct technical term here though)

(with picture)

Re: iPhone audio detectable with AM radio

#54

Post by evgen »

SiempreViernes wrote: post #41
evgen wrote: post #30

Earlier quoted context omitted.

Apparently you have no idea what you are talking about, so you think that these sorts of arguments work when discussing FCC emission testing. The FCC does not actually run the test, they set the standards. The tests themselves are run by various labs and testing agencies that are certified to perform the tests and who would be risking a very lucrative gig for the sake of cheating on a test for a device that will be w…

Hilariously, this is what I found when searching for the public test results of the iphone8, apologies for it being about a previous generation, but happily your argument is insensitive to such details: https://www.chicagotribune.com/investigations/ct-cell-phone-... The summary of the above article is that yes: if you hold the phone sufficiently far away from the measuring device the detected radiation is below the l…

Lol, 2mm. That is the distance this test used that you claim is some sort of support for your argument in this case. Sorry, but the only other corroborating evidence is a later claim made by a company that sells RF-shielded phone cases. I am going to have to chalk this one up to unclear guidelines (mis)interpreted by people who do not understand the square power law.

Try again.

Re: iPhone audio detectable with AM radio

#55

Post by abyssin »

emsy wrote: post #31

My neighbor is a Ham radio operator (don’t remember which frequencies are used in Germany). I sometimes can pick up the incoming radio signal. He explained to me it’s most likely the amp de-modulating the signal that is fed into the power line and my headphone cable acting as an antenna. When I first heard voices speaking I was a little freaked out for a moment I have to admit.

I remember picking up the conversation coming from a hot air balloon one day I was playing on the computer. I was focused on the game, and suddenly these voices start overlapping with the sounds I'm used. Today I'm not even sure it was possible. The speakers were that kind that made a noise when receiving or sending an SMS from a nearby mobile phone.

Re: iPhone audio detectable with AM radio

#56

Post by gok »

KMnO4 wrote: post #49
exikyut wrote: post #44

Earlier quoted context omitted.

That is admittedly really cool. It's nice to hear that these sorts of things are just quietly included, maintained, and work well, without widespread fanfare/marketing/publicity. Hmm. I wonder how they could be practically compromised...

This reminds me of the "car recall" evaluation from Fight Club: > Take the number of vehicles in the field, A, multiply by the probable rate of failure, B, multiply by the average out-of-court settlement, C. A times B times C equals X. If X is less than the cost of a recall, we don't do one. However, in this case, it would be: Take the number of people who would benefit from accessibility features, A, multiply by the…

FWIW, the CEO somewhat infamously snapped at an activist investor:

> When we work on making our devices accessible by the blind, I don’t consider the bloody ROI.

Re: iPhone audio detectable with AM radio

#57

Post by glitcher »

evgen wrote: post #54
SiempreViernes wrote: post #41

Earlier quoted context omitted.

Hilariously, this is what I found when searching for the public test results of the iphone8, apologies for it being about a previous generation, but happily your argument is insensitive to such details: https://www.chicagotribune.com/investigations/ct-cell-phone-... The summary of the above article is that yes: if you hold the phone sufficiently far away from the measuring device the detected radiation is below the l…

Lol, 2mm. That is the distance this test used that you claim is some sort of support for your argument in this case. Sorry, but the only other corroborating evidence is a later claim made by a company that sells RF-shielded phone cases. I am going to have to chalk this one up to unclear guidelines (mis)interpreted by people who do not understand the square power law. Try again.

I feel like you may have very good points to contribute, but your dismissive and combative tone is kinda ruining it for me.

Re: iPhone audio detectable with AM radio

#58

Post by jwandborg »

amelius wrote: post #23

I've found that the iPhone display is quite easily detectable between 400nm and 700nm wavelengths.

That sounds way worse since it's in the frequency range of many high-powered lasers.

It's also in the range of many low-power lasers, but I'm not worried about them.

Re: iPhone audio detectable with AM radio

#59

Post by floatingatoll »

0-_-0 wrote: post #33
IndrekR wrote: post #22

Most likely not an FCC (EMC) issue. This sounds like direct inductive coupling from speaker D class amplifier output (or power, which would be worse, but not likely) circuit at Why it is not an issue, is that magnetic field decays really rapidly, (inversely proportional to the cube of the distance [1]) and thus is not a general concern. In fact some "secure by physics" nearby communication methods like RuBee [2] rela…

A later tweet says "I was able to hear it from 20 feet."

I can hear the iPhone’s speaker from 20 feet away, too - without using AM radio technology to do so. (It’s a curse, trust me.)

Re: iPhone audio detectable with AM radio

#60

Post by floatingatoll »

geerlingguy wrote: post #47

I just tested this on my iPhone XS with both an old AM radio and my SDR receiver, and neither seemed to cause any kind of signal or interference around the 930-980 KHz range. My dad, a radio engineer (who worked for one of the US' largest AM radio stations for a decade), also tested with his XR and couldn't find any signal. I'm wondering if either it is limited to the iPhone 7 and/or 8, or if the Twitter OP might hav…

Retest with the hearing aid settings enabled?

https://news.ycombinator.com/item?id=24363153

To activate Hearing Aid Compatibility on an iPhone with iOS 13 or later, go to Settings > Accessibility > Hearing Devices. On these iPhone models, Hearing Aid Compatibility modifies the phone’s acoustic settings to improve compatibility with hearing aids set in "T" or telecoil mode.

If you have an iPhone 6 or earlier, you can activate Hearing Aid Mode. To activate Hearing Aid Mode, go to Settings > General > Accessibility. Hearing Aid Mode reduces the transmission power of the cellular radio in the GSM 1900 MHz band, which may result in decreased 2G cellular coverage.

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