Originally Posted By: mlord

It's probably just the phone's internals doing it -- eg. tiny spikes from switching the Tx power on/off 200+ times/second. Not the actual 850/900/1800/1900Mhz RF signal.

Cheers
The problem is the unshielded amplifier rectifying the RF signal. Any non-TX signal needs to be well below the TX level for spurious output specifications, usually at least 60dB down from the carrier.