The tachyon funnel was a powerful weapon developed by Egrorian, probably derived from his understanding of parallel matter. Egrorian claimed that the tachyon funnel could destroy anything, instantly, completely, and at any range. As a demonstration Egrorian destroyed Porphyrus, a lunar satellite 17 light years away.
Eight neutrons formed the core of the accelerator.
Development of the tachyon funnel had apparently begun over ten years previously, but further funding had been blocked by the senior administrators at the Space Research Institute. It can be deduced that Egrorian's subsequent disappearance was assisted by Servalan, presumably to allow him to complete the tachyon funnel for her own use.
Egrorian attempted to give Avon the tachyon funnel in exchange for Orac, later intending to recover it when the overloaded shuttle crashed back on Malodar. He threatened to turn the weapon on Scorpio if Avon did not agree.
The funnel was presumably destroyed when it was jettisoned by Avon in his attempt to lighten the shuttle, presumably destroying it. (TV: Orbit)