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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsFrom March 9: Sister of MH370 passenger calls brother and phone keeps ringing
If you call a cell phone that's unreachable, it goes straight to voice mail. I haven't forgotten this story from the first day after the disappearance. A sister called her brothers cell phone and it rang. In theory, someone should be able to track the history and location of that cell phone. Maybe those passengers are alive somewhere.
This video shows the moment relatives of a Chinese man among the 239 people feared dead after the passenger jet mysteriously disappeared rang his phone live on state television.
The call connected, but then rang out.
Chinese media reports that a number of families have been able to ring mobile phones of their missing loved ones but no one answers.
http://www.mirror.co.uk/news/world-news/missing-malaysia-airlines-eerie-moment-3222919
Cha
(297,323 posts)I never forgot this story. I thought it was pretty strange at the time. Either the guy didn't make the plane or something unimaginable happened.
Cha
(297,323 posts)it had been crashed or under water?
Renew Deal
(81,866 posts)Under water, almost certainly not. Even if a phone works under water, I'm not sure it can work at the depths of the seas and oceans involved. And it would have to be close to a cell tower.
Cha
(297,323 posts)".. But Luigi Maraldi contacted his family to say he was safe and well and Christian Kozel was found at home by Austrian police.
The revelations raise the fear that terrorism may have played a part in the sudden disappearance of the air liner that was flying from Kuala Lumpur to Beijing."
Aerows
(39,961 posts)confusing stew this entire story is. I hope the people are okay.
csziggy
(34,136 posts)Of course, my dead phone does not ring. Same when my husband's phone battery is dead and I call it. I hear a ring, he hears nothing.
Cell phones do not work the same as landlines.
A telephone ring is the sound generated when there is an incoming telephone call. The term originated from the fact that telephones originally had a ringing mechanism consisting of metal bells and an electromagnetically-driven clapper, producing a ringing sound. The electrical signal powered the electromagnets which would rapidly move and release the clapper, striking the bells. This electromagnetic bell system is still in widespread use. The ringing signal sent to a customer's telephone is 90 volts AC at a frequency of 20 hertz in North America. In Europe it is around 60-90 volts AC at a frequency of 25 hertz. Some non-Bell system party lines in the US used multiple frequencies (20/30/40 Hz, 22/33/44 Hz, etc.) to allow "selective" ringing.
http://en.wikipedia.org/wiki/Ringtone#Background
"What it means is the network is at work, trying to locate the party you are calling," he says. "It rings once, twice, three times, and if it finds the phone, it delivers the call. If it doesnt find the phone, then the call is disconnected."
Family members over there are hearing the [ring] tone and they are hoping, but this is not a sign of anything. This is just how the networks work," Kagan says.
That ringing sound to which we're so accustomed is actually a psychological trick, meant to keep us on the line while the network works to locate the other phone.
"The ringing sound is generated by the originating carrier's switch while the network sets up the call," a CTIA-The Wireless Association spokesperson tells Mashable. "This keeps callers from abandoning the call when they hear no sound. The ringing sound has nothing to do with the actual 'ringing' of the called party's device."
http://mashable.com/2014/03/11/why-malaysia-airlines-passengers-phones-ring/
uppityperson
(115,677 posts)jberryhill
(62,444 posts)It's like a whole body of myths and superstitions which try to make sense of technology. A 21st Century cargo cult.
FarCenter
(19,429 posts)It's been decades since the ring back was derived from the actual ringing signal supplied over copper wires to the bell in the telephone set. Since they are being supplied from different sources, sometimes a called party will pick up before the calling party hears any ring back.
csziggy
(34,136 posts)But landlines still get direct connection. If the landline is down, and I call the phone at my house, the phone company provides a message that the phone is out of service. Since I still use a physical message machine, I can also test to see if the power is back on at my house when we've had outages.
Not so for a cell phone. Cell phone companies attempt a connection and while they do so you hear ringing, then re-route to voice mail or a message.
FarCenter
(19,429 posts)But yes, the old telecom switches did a "loop test" on twisted copper pairs to check loop integrity.
jberryhill
(62,444 posts)How service signals are, or are not, translated across international boundaries between carriers depends to some extent on those carriers.
Which is really weird the first time you dial someone's US cell phone number when they are in the UK, get back a UK ringing signal and initially think you must have accidentally dialed a UK number.
All kinds of things happen with service signals.
longship
(40,416 posts)And may be sent back before connection is made as a feedback to the caller. This makes sense because the system sometimes needs time to locate the cell the called phone is in.
Apparently just because they get a ring, does not imply that there is a phone active on the other end.
FYI.
jberryhill
(62,444 posts)"If you call a cell phone that's unreachable, it goes straight to voice mail"
Have you EVER tried to make international cell calls between Asian countries?
What happens when a cell phone is unreachable is not some inherent God-given capability of cell phones, but is a result of how any of several different telephone networks talk to each other and are programmed to respond.
IF any cell phone aboard that plane were working, there would be an immediate fix on its location. But, no, as any of several networks get into a loop trying to find it, the caller hears a ringing tone back.
It's not as if all of the telecom networks in the world are run according to Ma Bell's Bible.
Trekologer
(997 posts)Most mobile carriers, if they even offer voice mail, charge extra for it.
jberryhill
(62,444 posts)csziggy
(34,136 posts)AUSTIN, Texas March 9, 2014 (AP)
Associated Press
Twenty employees of an Austin-based technology company on board the missing Malaysia Airlines flight were en route to a business meeting in China, a spokeswoman for the tech firm said Sunday.
The employees 12 from Malaysia and eight from China work at facilities in their respective countries that manufacture semiconductor chips, said Freescale Semiconductor spokeswoman Jacey Zuniga.
"We have several manufacturing sites in Kuala Lumpur and Tianjin, China. Those 20 employees were with those teams," she said.
The employees were aboard Flight MH370, which lost contact with ground controllers somewhere between Malaysia and Vietnam after leaving Kuala Lumpur early Saturday morning for Beijing. The plane was carrying 239 people.
http://abcnews.go.com/US/wireStory/austin-tech-firm-20-employees-missing-plane-22835999
There were also nine management employees of the same company going to the same meeting that took a different plane.
jberryhill
(62,444 posts)Lots of tech folks in Asia.
I'll be on a plane next week to a tech policy meeting in Singapore, and there will probably be quite a few going to the same meeting on that flight.
That's the thing about meetings - they tend to require a bunch of people in the same place at the same time, and will likely result in groups going to that meeting on the same airplanes.
So what?