Q-35 Matter Modulator

The Q-35 matter modulator, (Quantum plasma modulation matter injection rifle version 35) is a unique version of the plasma rifle in Fallout: New Vegas.

Characteristics
There are numerous differences notable between this weapon and the standard variant in terms of combat capability: As with most unique weapons, this weapon cannot receive modifications. However, its projectile velocity is similar to that of its standard variant with the magnetic accelerator modification. It also has a dark red and black color scheme as opposed to the normal gray; interestingly enough, the microfusion cells used as ammunition also follow the color scheme and appear red and black. This causes the cells to appear similar to electron charge packs.
 * Uses one microfusion cell per shot instead of two.
 * Rate of fire is twice as fast.
 * Degrades slower.
 * 50% extra damage per second (DPS).
 * Causes 7 less damage per shot but 15 more critical damage.
 * Uses 2 Less AP in V.A.T.S
 * Weighs 1 pound less than the standard variant.

Durability
The Q-35 matter modulator can fire a total of about 1245 times using standard cells, the equivalent of 104 reloads, from full condition before breaking. Despite being considered "unsuitable for prolonged field use," it has the second highest item HP of all the rifle type energy weapons (laser RCW having the highest), at 250 HP; more than triple the durability of a standard plasma rifle (which has 75 HP).

Variants

 * Plasma rifle - The common variant found in Fallout: New Vegas.
 * Van Graff plasma rifle - A special variant given by the Van Graffs.

Location
The weapon is located in REPCONN Headquarters, behind a locked (100 Lockpick skill to open) door. There is also a wall terminal (100 Science to hack) next to the door that can also be used.

Alternative Routes
You can also obtain the weapon by going through all of the building's floors, in which you'll find alternate routes or keys to unlock the door.
 * As you advance through the building's floors, mobile facial scanner robots will constantly ask for your identification. Failing to do so after 30 seconds will cause them to alert sentry bots to your presence. The facial scanners can be destroyed stealthily or before the 30-second mark ends. You can also prevent this by having a keycard (which the facial scanners will recognize in the second floor), or by adding your face to the facial database in that particular floor.
 * On the second floor, look for the hard locked door (requires 75 Lockpick) that leads to the main office floor. There will be a hole in the ground in which you can jump down, leading you to the room where the rifle is found. To exit the room, you can just climb back up the rubble and back into the second floor or you can use the Terminal near the Door to open it.
 * Additionally, it is possible to obtain the weapon by going to the third floor and searching the brief case found near the dead Brotherhood paladins' corpses; it contains a keycard which grants access to the room with the rifle.

Behind the scenes

 * The name is a reference to the fictitious "Illudium Q-36 Explosive Space Modulator" (sometimes "PU-36 Space Modulator"), a weapon that is always unsuccessfully deployed by the Warner Brothers' cartoon character Marvin the Martian in efforts to destroy planet Earth.

Bugs

 * If picked up, the gun could cause problems when loading a game. When loading it, the console reads "cannot open file because there are some mods that cannot be held". There is no known fix.
 * The gun may be wedged in the wall, making it difficult to retrieve. If you go up against the wall in third person, you can aim at the ground and grab the gun. Another option is to use C-4 to move the gun until you can grab it.
 * Often, the gun will not be found floating in the middle of the capsule as shown in the images below. It will be on the floor beside the container.
 * Sometimes the gun will appear stuck in the bottom of the container, making it difficult to get. Leaving the building then entering may fix this.
 * When you drop the weapon, it will become invisible, making it hard to find. The "Pick up" text will still be visible, however.