VG-2/Spectre Radar Detector Detection (RDD) You can think of VG-2 as law enforcement striking back against radar detectors. VG-2 identifies vehicles with operating radar detectors, by seeking out emitted frequencies from the tuning oscillators of radar detectors. Fortunately, most detectors provide some form of protection against this technology. Detectors with VG-2 immunity are shielded from VG-2 without interrupting radar and laser protection. Other detectors simply emit a warning and shut down automatically when they sniff out VG-2 signals.
Spectre RDD sweeps a larger spectrum than VG-2 and also covers multiple bands, making it more difficult to elude. It is used primarily in areas where radar detectors are illegal, or to track detectors in commercial vehicles. Only a handful of detectors today claim to be completely invisible to both Spectre and VG-2 RDD.