them to find and track the target normally. This mode, called "home-on-jam", actually makes the missile's job easier. Some missile seekers actually target the enemy's radiation sources, and are therefore called "anti-radiation missiles" (ARMs). The jamming in this case effectively becomes a beacon announcing the presence and location of the transmitter. This makes the use of such ECM a difficult decision – it may serve to obscure an exact location from non-ARMs, but in doing so it must put the jamming vehicle at risk of being targeted and hit by ARMs. See also Jamming Electronic warfare Electronic warfare support measures Wartime reserve mode References Raytheon ECCM-capable radio set Camp Evans Engineers develop World War II counter-measures with the help of Allen B. DuMont. Electronic countermeasures Electronic warfare Military technology Military communications Missile technology Radar signal processing Electronic counter-countermeasures