Students successful with £90 space camera

Comments

• A mobile phone operating at that height ? Dubious. Especially since the FCC forbids mobile phones being used in airplanes which travel alot lower in the atmosphere. Posted by adrianaitken, United Kingdom
• I dont think the phone had to actually do anything at that height, its role was just to tell people where it was once it was back on the ground. And the reason mobile phones are currently banned on planes is precisely because they can work at that height - if they didnt, they wouldn't have to ban them... Posted by Sam White, UK
• Sam, the reason phones are banned at that height is because of the cell structure of the masts (which is why Americans call them cell-phones, not because they use them in prisons but because of the technology!!).
  If you are high up your phone registers (or can register) in 2 or more places, depending on how many masts they 'see'. This causes major problems for the mobile operators because when someone calls you, which mast do they send the call out off ? Or if you're doing data, where does the data stream come from (and possible duplicate sending and therefore charging) and where does it want to get returned to?
  When you move (in a train etc), you seemlessly get switched from one mast to another. This is the 'cell' part of the equation. Each mast just touches the area bounded by the next mast and strongest signal wins. Obviously when you lose the signal it's because there are no masts covering that area !!!
  If you register on two masts they would be forever trying to switch you to the other mast causing infinate loops and the masts would probably explode :-)
  The urban myth that it interferes with planes electronics is complete tosh by the way. Posted by adrianaitken, United Kingdom