Heartbeat Sensor



The Heartbeat Sensor is an attachment used in Call of Duty: Modern Warfare 2. The attachment allows the user to track multiple targets, somewhat like UAV and similar to the motion trackers in the Halo games (though the latter is a 360 degrees detector with immediate update, built into the armor) and notably, to the motion tracker in the Aliens movie (despite it not being a separate piece of equipment). It displays the positions of people who are fairly close to and in front of the player.

In the campaign, the display screen can be folded out from the side of the weapon and folded back in again. The first time it is used is in the level Cliffhanger, where Roach finds himself in near white-out conditions. It is used also in the levels Contingency mounted on two M240s and in Just Like Old Times if the player, as Soap, swaps his weapon to the Silenced ACR. The sensor uses some kind of IFF system to tell the difference between friendlies and enemies. Friendlies are blue dots and enemies are white. In multiplayer games, friendlies appear as green dots instead of blue and enemies appear as red dots instead of white.

The new version of the perk UAV Jammer, Cold-Blooded, cannot bypass the sensor; only the perk Ninja can. The EMP killstreak will render it inoperative for the duration of the killstreak, however, so that only static can be seen on the screen. This attachment is compatible with assault rifles, light machine guns, and sniper rifles. It is also seen on the AA-12 in a few Special Ops missions such as Acceptable Losses. To unlock the Heartbeat Sensor the player must get 15 suppressed kills with the weapon.



Advantages

 * The Heartbeat Sensor allows the user to locate non-firing enemies without the use of a UAV. This makes it useful in Hardcore or when a Counter-UAV is airborne.
 * Unlike the UAV, the Heartbeat Sensor can detect players using the Cold-Blooded perk.
 * It is especially effective for snipers to have this equipped as it can alert them of an approaching enemy, unless said enemy is using Ninja or is coming from behind.
 * The Heartbeat Sensor helps its user locate enemies through any obstructions, such as walls and smoke screens.
 * When used by one member in Team Deathmatch who has a microphone, it can be useful when going into buildings after players hiding. The person with the Heartbeat Sensor can pinpoint and announce the location of the player(s) to his/her team.
 * A player can use the Heartbeat Sensor effectively even without looking at it, as the Heartbeat Sensor beeps when it detects enemies.
 * The Heartbeat Sensor can be used while utilizing a grenade launcher.

Disadvantages

 * There is a fairly long period of time (slightly longer than a UAV) between sweeps.
 * When reloading a Grenade Launcher, the Sensor will obstruct the middle of the screen.
 * Enemies with Ninja will be able to easily surprise someone using the Heartbeat Sensor. This makes the Heartbeat Sensor inadvisable for Search and Destroy.
 * This attachment is almost useless in third-person, because the player cannot see the sensor.
 * Players using a heartbeat sensor can inadvertently give away the positions of their teammates, if the victim watches the shooter's Kill-Cam.
 * In single player, the display cannot be seen while using night vision goggles. The sensor will glow brightly making it impossible to see.
 * The sensor only scans the area in front of and to the sides of the player. Enemies behind the player cannot be detected unless they are directly behind the player.
 * In two-player splitscreen, the Heartbeat Sensor is off the bottom of the screen on some guns (E.g LMG), making it almost useless, and a waste of an attachment. In three-player, only the last player will experience this.
 * When using the Heartbeat Sensor many people tend to stare down at the sensor, allowing people using the Ninja perk to surprise attack them. Some say the Heartbeat Sensor can be a distraction at times.
 * The sensor can be very confusing in multi-story buildings as it will beep even if the opponent is on a different floor.
 * Sprinting will obscure your Heartbeat Sensors view.

Trivia

 * Originally the Heartbeat Sensor may have been meant for some Sub Machine Guns, this can be seen on the P90's unused tactical rail on the left side of the gun.
 * The Heartbeat Sensor you use in the Campaign shows enemies as white dots and allies as blue dots, the scanner in multiplayer shows enemies as red dots, and allies as green dots.
 * The Heartbeat Sensor does not pick up the heartbeat of chickens or civilians.
 * The Heartbeat Sensor cannot be folded back towards the gun in multiplayer.
 * The Heartbeat Sensor has a smaller range of detection in multiplayer. This was done for balancing purposes.
 * The Heartbeat Sensor has a range of approximately 30 meters in singleplayer.
 * On multiplayer, this attachment is available on all Primary Weapons except for Sub Machine Guns and, obviously, the Riot Shield.
 * The player will get a fuzzy screen when the enemy team uses an EMP.
 * It is strange how the heartbeat sensor can detect which people are enemies and which ones are allies just by their heartbeat. Of course, this is obviously just for gameplay purposes. A possibility could be that the player's allies have some sort of device on them like an IFF transmitter that makes them appear as a blue dot, instead of white or red.
 * If the above is true then its wierd that when you infiltrate Hotel Bravo that the Shadow Company forces are marked as enemies when they would have the same IFF system that would make them not marked as enemies.
 * In Special Ops, an AA-12 with a heartbeat sensor can be used. The heartbeat sensor is not available in multiplayer on the AA-12 or any other secondary weapon.
 * In real life, there are actually devices that sense heartbeats, but they are larger than the one in MW2, about the size of a radar gun. As the game takes place in 2016, new advances to reduce size may have been made.
 * There is a currently existing heartbeat sensor, but is extremely sensitive to electronic objects, rendering it useless unless in desert warfare.
 * The Heartbeat Sensor is very hard to use in split-screen mode because the screen is smaller. Only a few weapons will show the whole screen, such as a Barrett .50cal or M4A1 while other guns like the SCAR-H or FAMAS don't show the screen at all.
 * When aiming down the sights with the TAR-21 with a MARS Sight, almost the entire heartbeat sensor screen is still visible.
 * Many players say they often end up watching the Heartbeat Sensor more than they actually look in front of themselves. This is counteracted by playing as though you don't have the Sensor until it detects an enemy and makes a ping, the pitch of which ascending as the enemy draws closer.
 * Some players choose not to use the Heartbeat Sensor due to the fact that it can be distracting at times, often leading to easily preventable deaths.
 * The Heartbeat Sensor is nearly identical to the motion trackers used in the movie Aliens, down to using the same blips for moving objects, and the same static beep when no movement is detected.
 * Due to the Heartbeat Sensor's loud beep when it detects enemies, players can still sprint or aim down the sights just as often as they normally would and only stop when a beep is heard.
 * The Heartbeat Sensor appears in many different sizes. When attached to the Barrett .50 Cal or the CheyTac Intervention, it is smaller than one ninth of the screen.
 * The beep is a lot more audible on the console versions than the PC version.
 * Some weapons' (SCAR-H, TAR-21, etc) reload animations differ with the heartbeat sensor attached. This is probably because the heartbeat sensor obstructs the charging handle (noticeable on SCAR).
 * In Battlefield: Bad Company 2, one of the characters, Sweetwater, makes a remark about how General Braidwood will send "some Special Ops douchebags with pussy-ass Heartbeat Monitors on their guns instead of us." He says this during a mission that takes place on snowy mountains while recovering a piece of a crashed satellite, which is extremely similar to the scenario in Cliffhanger.