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Why Cell Phones Make Speakers Go "Blip Blip Blip Buzz"

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When I first got a cell phone (an early Sidekick), a new noise entered my life. When I put on my big crazy headphones while the phone was in my shirt pocket, I'd hear a very distinctive "blip ba da blip ba da blip ba da buzzzzzzz" noise right before my phone rang, so loud that I'd have to wrench the headphones from my poor ears -- which was handy, because then I'd hear the phone ringing. It took me a long time to figure out that this noise was coming from the phone, because I'm kind of slow. I also heard it when the phone was near mostly any speakers (even my TV set), including when I received text messages or used other data features on the phone. I recently saw a discussion of these noises on a fellow _flosser's blog post. So what causes this noise?

Basically, it's the cell phone talking to the tower, and nearby speakers picking up that radio transmission. There are several Metafilter articles on the subject, which make for good background reading. The best technical explanation I've seen of the phenonemon I've seen is on this WiFi-Forum post:

The type of interference can occur if the following things happen
together:
1) a pulsing radio transmitter,
2) with relatively strong power,
3) in very close proximity,
4) to a non-linear circuit element.

The non-linear circuit element is usually some sort of solid state
device such as a transistor or diode. If the non-linear element is
subjected to a strong pulsing radio signal, it will act as a rectifier
and "detect" the pulsating waveform, i.e., convert the pulsations from
a radio frequency to an audio frequency (if the pulsation rate is in
the pass-band of audio frequencies.) For example, a hearing aid
consists of a microphone, an audio amplifier and a small speaker. If
a strong pulsating radio signal impinges upon the first transistor
amplifier stage, the transistor will be driven into its non-linear
range and detect the pulsations. If the pulsation rate is in the
audio frequency range, the rest of the hearing aid amplifier will
amplify this and deliver it to the speaker, to the great annoyance of
the hearing aid wearer.

This annoyance is endemic to certain digital cellular technologies (including ones used in music devices like the iPhone, eek). The only ways I've found to mitigate the sound are: move the phone and the speakers father apart (this only seems to reduce the noise a bit...), turn off the cellular portion of the phone (the iPhone, for example, has an "airplane mode" that makes it practical to play music in the car -- without this turned on, the car sounds like it's being ripped apart by buzz-saws), or introduce electromagnetic shielding (good luck building your Faraday cage).

If you've got tips on how to reduce this noise, or a story of how annoying it is, please share in the comments.

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A Voice Recognition App Adds Sound Effects While You Read to Your Kids
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iStock

Technology is coming for kids’ story time, but maybe not in the way that you think. The future of bedtime stories, as MIT Technology Review describes it, won’t involve tablets or reading off screens, but it will have sound effects.

Novel Effect is an app that uses voice recognition to track the bedtime stories you’re reading to your kids and insert sound effects and music in response to certain cue words. It’s similar to a home assistant, such as the Amazon Echo or Google Home, except instead of playing music and setting kitchen timers for you, it’s on the ear-out for keywords contained in certain kids’ books.

Four mobile app screenshots side-by-side of the Novel Effect app.
Novel Effect

The app doesn’t work for all titles, but it offers effects for popular books you probably already own, like Where the Wild Things Are, The Hungry Caterpillar, and The Cat in the Hat. When you open the app on your phone, you select which book you plan to read. As you read the physical book out loud, the app listens for where you are in the text and adds sound effects, from dramatic music to monstrous roars.

It’s not going to trigger odd sound effects every time you say the word “caterpillar,” though. (Unlike the Amazon Echos that heard the words “Alexa, buy me a dollhouse” on a TV news report and rushed to fulfill the order.) The words have to correspond to the book you’ve selected in the app, though you don’t have to read the text from the beginning or keep any specific time. The app can recognize where you are in the book no matter where you start or whether you dive off into a tangent about how cool caterpillars are before resuming the story.

Novel Effect is part of Amazon’s Alexa Accelerator for voice recognition technology, and it seems feasible that one day this kind of functionality would be a skill you could enable on your Echo or other voice-controlled assistant. According to MIT Technology Review, the company hopes to allow users to create their own sound effects sometime in the near future.

[h/t MIT Technology Review]

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Volkswagen Introduces Electric Version of Classic Microbus
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Volkswagen

Following the success of the compact Volkswagen Beetle, German automaker Volkswagen expanded its line in 1950 with the release of the Type 2. Customers preferred a less clinical name, opting to call it the camper, the bus, or the transporter. Able to tote mass quantities of counter-culture protesters, the Volkswagen bus became a symbol in antiwar movements of the 1960s before disappearing to the scrap heap of expired popular culture.

Recently, the company has doubled down on claims it would be revisiting it as a smaller vehicle. At a recent presentation at a Pebble Beach charity car expo, Volkswagen announced the bus—previously identified as the I.D. Buzz—would be returning in 2022 as a fully electric and consolidated version of the classic.

A look at the interior of the Volkswagen Microbus
Volkswagen

CEO Herbert Diess said that prototype versions of the vehicle on display at recent trade shows led to encouraging feedback that convinced the company to move forward. The I.D. Buzz is expected to have 369 horsepower, a considerable boost from the 25 of the original, and might implement self-driving elements. The concept car—which may or may not make it to roads with all of the same features—has a retractable wheel and movable seats when autonomy is engaged. The future of cars is looking more and more like a portable living room.

[h/t Inhabitat]

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