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How Mobile Phones Work Behind the Scenes
adamengst writes "We seldom think about how our mobile phones actually work, but in this TidBITS article, Rich Mogull pulls back the covers and peels away the jargon to explain why text messages work when voice calls are dropped, why your battery lasts longer in some places than in others, why you're not allowed to use phones on airplanes, why you can be notified of a voicemail message when your phone never rang, and more."
>>>Or why a text message can get through when a call can't?
This is no great mystery. A test message can just sit in a buffer until your phone is within broadcast distance, and then it's sent. But a call has to be done in realtime; if reception is poor the caller gets a busy signal (and then send a text instead).
The government is not your daddy. Its purpose is not to raid middle-class neighbors' wallets and give it to you.
why you're not allowed to use phones on airplanes
One crash in light aircraft ages ago suggested possible connection, unlikely.
How about "You're a loud-talking asshole and you're enclosed in a tight, cylindrical object for several hours with a couple of hundred other people who don't want to hear about your stupid business plan."
Does it make you happy you're so strange?
3. You're not allowed to use phones on airplanes because of paranoid ignoramuses and the insightful people who realize how bad it could get when people in a flying bomb know what's going on (and how annoying cell phones are).
Or, just possibly it's because:
1. GSM phones are known to emit strong pulses of RF that interfere with nearby electronics (audio amplifiers, televisions, speakerphones, etc).
2. Airplanes contain quite a few important electronic systems for navigation, communication, flight control, etc.
3. Considering the number of passengers who are carried by airplanes each year, even something with a one-in-a-million chance of causing a problem would be a very bad thing.