Guided by the knowledge of the Ancients, O'Neill constructed a device, using the power crystal from a staff weapon, which transferred ten times more energy than usual to the stargate's capacitors. The energy generator enabled the gate to dial the Asgard homeworld of Othala, an address using 8 glyphs, far outside the known stargate network. The generator was designed to be used once, but Carter and her counterpart from an alternate reality were later able to repair it by using the ratio of the decay rate of naquadah relative to the energy output. The device was used again to contact the Asgard in a parallel universe, but it was then left behind in the alternate reality.
Cross Reference: Alternate Reality - Quantum Mirror, Ancients, Ancient Repository, Asgard, Othala
Episode Reference: The Fifth Race, Point of View