The Gundam Wiki
The Gundam Wiki

The Neutron Jammer Canceller (ニュートロンジャマーキャンセラー) (also called N-Jammer Canceller) is a device introduced in Mobile Suit Gundam SEED.


A device used to disable the effects of Neutron Jammers. When activated, nuclear fission becomes possible, and radio disturbance and the like will no longer occur. However, while the N-Jammers had a vast working area, the N-Jammer Cancellers only worked in a small area, which means, that any nuclear reactor or weapon intended to work under N-Jammer effect has to be outfitted with their own N-Jammer Canceller.

To create N-Jammer Cancellers, a rare material is needed, which is controlled by PLANT and on Earth by the Atlantic Federation. On Mars however, this material exists in large amounts. This is, however kept a secret by its inhabitants to prevent any superpower from attacking them.

The "G.U.N.D.A.M" acronym for Mobile Suits equipped with N-Jammer Cancellers is: Generation Unsubdued Nuclear Drive Assault Module.


ZAFT deployed Neutron Jammers to disallow the Earth Alliance use of nuclear weaponry and reliable power generation. This however forced ZAFT to use weaker weaponry and energy sources as well. Eventually, the Coordinators invented the N-Jammer Cancellers to cancel the N-Jammers' effect in order to use nuclear weapons and generators. This would mean nearly limitless supply of energy and a complete superiority over other battery powered Mobile Suits that had to be recharged periodically. The device was eventually installed into the first five Gundams created by ZAFT themselves. The power of such a nuclear-powered suit was displayed when the ZGMF-X09A Justice Gundam and ZGMF-X10A Freedom Gundam outlasted three battery powered Mobile Suits in a fight while constantly using powerful weapons.[1]

The N-Jammer Canceller was designed by PLANT Supreme Council member Yuri Amalfi, father of ZAFT Red Coat and GAT-X207 Blitz Gundam pilot Nicol Amalfi. However, after the death of his son in battle,[2] he buried himself in his work, leading to the construction of the N-Jammer Canceller much sooner. The device was first tested using the YMF-X000A Dreadnought Gundam and then implemented in the Justice Gundam, Freedom Gundam, and other ZGMF-X series mobile suits created during the war.

Due to the fact that the N-Jammer Cancellers would allow the Earth Alliance to use their nuclear weapons again, their existence was kept a tight secret, even among ZAFT's leadership. Thus, when the existence of the powerful Justice and Freedom became known, the EA sought to get ahold of both of units. The technology eventually fell into the hands of the EA when insane ZAFT commander Rau Le Creuset sent the device's data to Blue Cosmos leader Muruta Azrael.[3] The EA quickly mass-produced the devices and outfitted their nuclear weapons with them, eventually launching a massive nuclear attack on PLANT.[4] ZAFT countered this attack with their own nuclear superweapon GENESIS, which was also outfitted with a N-Jammer Canceller.[4] During this time, an N-Jammer Canceller was stolen by Canard Pars for the CAT1-X1/3 Hyperion Gundam Unit 1.

Because the use of N-Jammers was banned by the Junius Treaty which ended the First Alliance-PLANT War, N-Jammer Cancellers are now semi-outdated technology; however, because of the still-present N-Jammers which were dropped on Earth during the war as offensive weapons, all nuclear power reactors on Earth are equipped with N-Jammer Cancellers. The prototype Neutron Stampeder weapon used during the Second Alliance-PLANT War appears to be derived from the N-Jammer Canceller technology.

Notes & Trivia

  • In Super Robot Wars series, the Neutron Jammer Canceller provides 15% energy refill (of the unit's total energy) per turn.
    • However, in Super Robot Wars J, the Neutron Jammer Canceller was not installed on Freedom, Justice or Providence. Thus, the units do not gain high energy refill per turn. This may have been an oversight on part of the programmers as other units from non-Gundam series with official energy regen in J still have some sort of ability to do so.
  • In SD Gundam G Generation World, it doesn't bestow high EN refill but rather negate the cost of using defensive abilities (such as Phase shift) and reduce all attacks' costs by 10%. In addition to the mechs that naturally have it, the effects can be provided by an item. This might have been done to prevent such units from creating balance problems as EN refilling parts/abilities are uncommon in the game.
  • In SD Gundam Capsule Fighter Online, the Neutron Jammer Canceller functions differently that in other games. For basic units like the ZGMF-X10A Freedom Gundam, it gives the unit infinite dashing at 50% HP. For units like the ZGMF-X20A Strike Freedom Gundam, it not only gives that, but also increases search range and activates radar.
  • In Mobile Suit Gundam SEED: Never Ending Tomorrow, mobile suits with the Neutron Jammer Canceller possess a regenerative Phase Shift gauge and the inability to suffer from Phase Shift Down status.
  • In Battle Assault 3 featuring Gundam SEED, mobile suits with the Neutron Jammer Canceller have a singular health bar, thus physical attacks instead do less damage as the normal armor and Phase Shift armor are together and the unit never suffers Phase Shift Down status once the PSA bar is gone.
  • In spite of all the seeming 'unlimited power' and effects given, the fact that SEED MS use fission reactions as opposed to fusion ones (which generate more energy) is overlooked.
  • In the Extreme Vs. series, only the Hyperion Gundam Unit 1's N-Jammer Canceller is manually usable as it increases the unit's overall performance such as increasing its damage, speed and ammunition but also reducing its ammo reload. Due to its power, N-Jammer Canceller can only be used once per life. The Justice Gundam's N-Jammer Canceller is also referenced in its lose pose, where its nuclear self-destruct is shown.


Television Series


Cosmic Era technology
Standard technology
Beam Shield | Deuterion Beam Energy Transfer System | Geschmeidig Panzer | Laminated Armor | Lightwave Barrier | Mirage Colloid | Mirage Colloid Stealth System | Phase Shift armor | Positron Blaster Cannon | Positron Reflector | Trans-Phase armor | Variable Phase Shift armor
Mobile Suit technology
DRAGOON system | G Project | METEOR | Multi Lock-on System | Operating Systems | Second Stage Series | Striker Packs | Voiture Lumiere
Cyclops System | GENESIS Alpha | GENESIS | Hyper-Deuterion Engine | Neo-GENESIS | Neutron Jammer | Neutron Jammer Canceller | Neutron Stampeder | Nibelung | Requiem
Human enhancements
Carbon Human | Coordinators | Extended humans | Newtypes | SEED factor