That's good! Clearly there was some manufacturing defect, physical damage, or more likely some illegal modification to this guy's device. It is common for high-speed digital electronics devices to generate EMI/RFI but it is supposed to be properly suppressed and shielded to prevent interfering with other nearby devices. If this device was emitting RFI with such a signal strength as to interrupt a major mobile network, the emissions had to be significant and that leads me to suspect an illegal modification to the device. It could have been something as simple as operating it with the case cover (which typically acts as shielding) removed for better cooling. Or it could have been some other unsanctioned modification to the design. I say this with some experience as an Air Force radio communications technician for many years. One of my "other hats" was to drive on and around military bases in a specially equipped truck with radio direction finding equipment looking for intentional (or unintentional) radio interference and "other sources" of unwanted RF signals.
