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An electromagnetic pulse (EMP) generator is an anti-electronics weapon that mimics the intense EM radiation created by a nuclear explosion in an atmosphere. The resulting EM field couples with nearby electronics systems, inducing electrical currents and voltages, thus damaging sensitive electronic equipment.
Just before the Cylon attack, "electric pulse generators" are being transported to Caprica from the decommissioned battlestar Galactica on Colonial Heavy 798, presumably to place in a planet side museum or school as a historical artifact, or for re-use on another ship (Miniseries).
As the destruction of the ship by Cylon nuclear missiles is imminent, Lee Adama activates the devices, giving the appearance that Colonial One had been destroyed by a nuclear blast. This ruse is successful, as the Cylons do not immediately return. The missiles were disabled by the EMP with an energy pulse so strong that Galactica's DRADIS picks up the pulse, which leaves William Adama grieving for the apparent loss of his last son.
The human passengers are stunned unconscious by the pulse as well, but soon recover. Colonial One's electronic systems seemed to be fully functional after the attack.
- These devices are probably standard equipment aboard ships such as battlestars, given Lee Adama's knowledge about the electric pulse generators.
- Such devices might have been part of a battlestar's fighting tactics against Cylon attacks in the first Cylon War, (but not in the second), since Cylons were purely mechanical at the time and their circuits were vulnerable to EMP attacks unless shielded. Given that a non-military craft such as Colonial One recovers very shortly after the pulse, the EMP may not be an effective ship-disabling weapon. Lee Adama mentions that simulations performed at the Colonial military academy resulted in low probabilities that a generated EMP would fool Cylon forces, suggesting that EMP's are a defense and deception tool rather than a weapon (Miniseries, Night 2).
- During the Fall of the Scorpion Fleet Shipyards, the battlestar Pegasus gains valuable time to escape by a blind jump when the radiation from the Cylons' nuclear weapons temporarily blinded their own DRADIS (Pegasus). 
- ↑ The Miniseries shows the EMP temporarily overloading the crew's central nervous system and causing unconsciousness. However, this is scientifically incorrect, because although the human nervous system works with electrical currents, there is no metal to act as antenna for the magnetic field and induce a damaging current. The effects shown are either a writing error, or the result of some other force.
- ↑ Admiral Cain says "the blast blinded the Cylon DRADIS", making it unclear to which physical phenomenon she refers to exactly. This effect is not an EMP in the strictest sense, since a significant EM field is only created when a nuclear detonation's gamma-ray emissions interact with the matter in an atmosphere and produce free electrons through compton scattering, which in turn interact with a planet's magnetic field. There are no nuclear EMPs in the vacuum of space. The gamma radiation generated by an explosion alone can nonetheless disrupt DRADIS and wireless communications, as they rely on a form of EM radiation as well. Another possibility is the interaction of the gamma radiation with vented atmosphere or the outer layers of the planet's atmosphere.