Originally Posted by
xyzzy
Please tell us -- was the study cited above based on .6 watt phones being used by each passenger or the old 3 watt bag phones? There's a HUGE difference. In any event, if the devices are allowed on aircraft there is always a chance that they will be left turned on, regardless of what the rules state.
It would appear that from your questioning you may have some knowledge of mobile phone technology and or electrics/electronics. Therefore I would expect you to understand that electromagnetic interference (EMI) is dependant on both the frequency and amplitude (strength) of the signal. When you ask if the tests were carried out using 3 watt or 0.6 watt units are you referring to the peak power output or average power output (i.e. allowing for multiplex or x 8 channel sharing)?
I am sure you will also know that a GSM and CDMA phone in close proximity will interfere with each other creating a signal at an entirely different frequency – a mutual interference product – that is very close to the band used by the aircraft's GPS and Distance Measuring Equipment (DME).
I must confess that my personal involvement with the in-flight testing took place in 1999 and in all probability did use mainly older technology mobile telephone equipment. However, I have followed the progress of other more recent testing carried out by my colleagues in the industry and have yet to see any clear facts that the more recent mobiles do not pose similar problems in present conditions.
While power output may have been decreased the number of phones now in use has increased many-fold.
I am not posting on this forum to educate or to force my opinions on others. I have just stated my humble, honest opinion. If this should give you or others any problems then I will cease posting. You obviously have a strong opinion on this subject and I respect that.
However, I reserve the right, if I see someone using a mobile phone or other transmitting device on my flight, to personally act to make sure my personal safety is not compromised.