Hi,

Does the mobile/cell phone tower affect phantom 2s? How far do you need to fly from these towers? What happens if you fly close to this?
Has anyone experienced anything with Mobile towers or its just a precaution.

another thing is has anyone flown close to electricity transformers? How does this affect?

Thanks

Any interference in the same frequency is a risk so that is up to you to determine, Certainly high tension lines are not without potential significant interference.
My preference is to stay away from anything bigger than me that is made of metal or could be broadcasting while flying...

I've been at about 1/4 mile from a Verizon cell tower but no interest to get closer.  There is nothing to see there.

From what I have been studying, there is very little outside of solar flares and such which will interfere with GPS signal.  But there are PLENTY of things which produce EMI, or electromagnetic interference, such as current running through high tension wires.  EMI produced by an EMF (electro magnetic field) can interfere with your compass.  So can large metal structures such as towers, cell phone towers, building with a lot of steel in them, etc.   If there is a problem with your compass reading such as an error induced by EMI, you are done, because the Phantom navigates using GPS and compass reading in conjunction.  If your compass reading is bad, bad things can happen.

Beside the football field where we often fly, the is a cell phone tower and we don't have any issues what so ever.
(More than 200 fights)

Read this.  It might enlighten some of you, might ease some minds as well.

From GPS Interference Testing:
"GPS out-of-band, or blocking, interference can result from an undesired response created by the mixing of an LTE signal with the local oscillator (LO) of a GPS receiver. The resulting undesired signals may be translated to the intermediate frequency (IF) stages as spurious response frequencies."

In other words, an LTE signal has the potential to interfere - no mention of how likely it is to happen though.

The problem for GPS in a copter is RFI interference issues.  Even the electronics in the copter can cause issue due to relatively small amounts of RF they emit but they are in close proximity to the GPS unit.  On a cell tower you have strong RF emissions that sometimes are beamed and concentrated for some distance from the tower.  Particularly the old microwave relay towers.  These strong emissions can couple with the relatively unsheilded wiring and circuits in many copters and significantly degrade signal to noise ratio.  Also you need to worry about your main radio control link.  Here also these strong emissions can degradation of range.  Part of the equation is what frequencies are on the tower, what is your RC control frequency, how close your are and the direction the tower antennas are pointing.  See the potential frequencies below.  Luckily signal strength decrease rapidly if the antenna is not too directional but I would be cautious generalizing about the safety of flying near towers.  I can guarantee in some cases it will end badly.  Give them as much distance as you can if in proximity and be aware of any unusual flight characteristics

http://en.wikipedia.org/wiki/Cellular_frequencies