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Author Topic: why does my mobile (cell) phone lose it's signal?  (Read 8468 times)

paul.fr

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Sit down or walk around with the phone in my hand, or arms crossed over my chest and i loose all signal strength. If the signal can travel through walls, etc. then why not my hands?
I also loose all signal strength when the phone has been in my pocket, trousers or jacket, for a while!


 

Offline engrByDayPianstByNight

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why does my mobile (cell) phone lose it's signal?
« Reply #1 on: 18/07/2008 21:19:12 »
You're right it should not lose signals so easily. Assuming wherever you're does have good cell-site coverage (your cellphone is connected to a cell site, or base station, when you're on a call) when this happens, the only thing I can think of is your cellphone has a bad transceiver, that is, a defective hardware problem. You might want to get a new phone.
 

paul.fr

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why does my mobile (cell) phone lose it's signal?
« Reply #2 on: 18/07/2008 22:14:59 »
Thanks, but it is a new phone! This has happened with every phone i have or have had.
 

lyner

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why does my mobile (cell) phone lose it's signal?
« Reply #3 on: 19/07/2008 14:34:41 »
I think you could not get a bob on the buses because it looks like you are a Bad Conductor - boom boom.
 

Offline techmind

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why does my mobile (cell) phone lose it's signal?
« Reply #4 on: 24/07/2008 00:10:33 »
Your body is a substantially conducting object (blood contains dissolved ions and is therefore fairly conductive) and will attenuate high-frequency radio signals and also "de-tune" small radio aerials if you put your body close to them.

In a strong signal area, these effects are not a problem as there's plenty of signal anyway.
In an area with already weak mobile phone signals, the action of putting the phone against your skin might be "the last straw".

With the older phones with the stubby-stick antennas, it was very obvious that if you gripped the antenna tightly in your fist the signal might drop from 3-bars to none (the phone usually takes a few seconds to show the drop, as the indicator averages the actual signal level over several seconds).

Low-signal-level results with mobile phones are often not very reproducible as the signal has a wavelength of only a few 100mm (so can be extremely position-sensitive) also the phone may switch between different weak base stations from minute to minute.

Another thing you might notice is that the mobiles' battery tends to run down more quickly when it's kept in a weak-signal area; "searching" for a signal takes more power than just happily remaining "in contact".
 

Offline TheHerbaholic

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why does my mobile (cell) phone lose it's signal?
« Reply #5 on: 05/08/2008 08:24:55 »
I never thought of that, techmind, interesting stuff.

But is it true that mobile phone transmitters are really quite cancerous because of the radioactivity?

Say if you lived on the doorstep of one of them for 50 years, how much would your chances of getting cancer go up by? Does anybody roughly know the answer?
 

lyner

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why does my mobile (cell) phone lose it's signal?
« Reply #6 on: 05/08/2008 11:44:38 »
Quote
http://news.bbc.co.uk/1/hi/health/7523109.stm
I heard about this the other day. Meanwhile, we have to watch that particular space to find out whether it is a real concern.
However - by operating the phones on a remote (1m mike and earphone connection) system, we should be safe, even if the worries are justified. (Even a v. low power bluetooth connection could make all the difference)
« Last Edit: 05/08/2008 15:27:38 by sophiecentaur »
 

Offline techmind

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why does my mobile (cell) phone lose it's signal?
« Reply #7 on: 09/08/2008 18:26:34 »
But is it true that mobile phone transmitters are really quite cancerous because of the radioactivity?

Mobile phone masts are not connected at all to radioactivity.

In physics, the term "radiation" is very general, and is applicable to thermal energy (the heat you feel from a bright orange/red fire or grill), visible light, radiowaves, microwaves (which are just a particular type of radiowaves, with a wavelength around 1 to 10cm, compared to FM radio which has about 3metre wavelength), etc. Of course the word "radiation" is also used for nuclear radiation... but this is NOT the only use of the word.

Mobile phones work at 900MHz (O2 and Vodafone GSM networks, only slightly higher freqency than normal UK terrestrial television), 1800MHz (Orange and T-Mobile, and some fill-in stations from O2 and Voda), and 2100MHz (all networks) for 3G coverage.

From lambda (wavelength) = c (speed of light) / f (frequency in Hertz)...
900MHz == 33.3cm
1800MHz == 16.7cm
2100MHz == 14.3cm
« Last Edit: 09/08/2008 18:28:40 by techmind »
 

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why does my mobile (cell) phone lose it's signal?
« Reply #7 on: 09/08/2008 18:26:34 »

 

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