Inquiry about emissions at NSA UDC and other data centers was not for external capture but about internal protection from its own emanating equipment. In particular EM interference by the big generators at most of the facilities, electrical sub-stations, processing racks, cabling, switches, personal devices, whatever is used to run the operation and whatever might be deployed by those hoping to capture inadvertent emissions by land, air, sat, mobile. If you will, what does NSA do to capture such emissions from data centers to data gathering and for unique signatures? This is not likely overlooked by NSA and maybe at the other burgeoning worldwide data centers, but what that protection might involve, ie, Large-scale TEMPEST countermeasures, somewhat larger than a nuclear submarine, maybe closer to large-scale array used to snoop on global EM and radio signals, mundane and heavenly. as with the NRAO. We have an interest in snooping on the emissions and protection against snooping of large buildings and infrastructure, from electrical grids to telecom hubs to internetworks to scientific networks to intellinks to satellites to space probes. The usual spy sci-fi beloved of hams.