Anti-radiation missile was achieved by the SAM site's radar receiver locking on to radio noise emissions generated by an aircraft's jamming pod. In cases of heavy jamming, missiles were often launched exclusively in this mode; this passive tracking meant that SAM sites could track targets without needing to emit any radar signals, and so American anti-radiation missiles could not be fired back in retaliation. Recently, the People's Republic of China developed the FT-2000 system to counter AEW and AWACS targets. This system is based on the HQ-9, which is in turn based on the S-300PMU. These anti-radiation missile systems have been marketed
A Sound Like Someone Trying Not to Make a Sound make a sound". The child wakes his father and describes the sound to him. The child believes that the sound comes from a "monster with no arms and legs", which "slides on its fur" and "pulls itself along on its teeth". The father and child discover that the sound is coming from the mice in the walls, and the child is comforted by his parent. The two return to sleep. A "Publishers Weekly" reviewer wrote that "In showing young readers that the things that go bump in the night are, in reality, not so scary, Irving succeeds in helping them