Also known as a psi blocker.
The psionic blocker is a very controversial device, developed by the Odarite Merchants Guild. One side argues that it champions freedom from undetectable mental manipulation, while the other argues that it suppresses telepaths' ability to defend themselves (or even to interact normally), as well as marginalizes their racial identity.
The typical psi blocker is a black box about the size and shape of a paperback book and easily clips onto a belt or other article of clothing. A sliding toggle on the side of the unit controls its operation. A small crystal telltale glows green when active, crimson when inactive. This type of case is designed to resist attempts at reverse-engineering.
Telepathic beings have been found to sense a sort of void around the user of an active Psi blocker, many describing it as sensually similar to the feeling of the void of space. Also, evidence suggests that the sinkhole produced by a Psi blocker can have side effects to telepathic beings that remain in its sphere of influence for more than a few hours, whether wearing it or in close proximity. These symptoms include a sensation of itching in and around one's brain, mild lightheadedness, feelings of claustrophobia, and in severe cases, paranoia and depression. This seems to be due to the natural need of most telepathic races to have a telepathic sense of the beings around them. Psychological damage seems to be similar to that experienced when put into solitary confinement. Prolonged exposure to psi blockers for more than a month has the potential of causing stronger psychological disorders, such as schizophrenia or autism, as the telepath's mind seeks to replace the void.
Of further note, these effects can vary based on the being's level of ability in telepathy. In beings with no psionic ability, the device has only an unnoticble dulling effect on the perception. The average Timonae likely wouldn't feel anything, while powerful telepaths like the Centaurans or Mystics would experience these effects much more acutely. Another common misconception is that psi blockers do not affect all psionic beings. Beings with psychokinetic and psychic abilities will also feel the effect of the psi blocker, manifesting itself as a dull throbbing white noise generated headache, visibly painful, making it a difficult task to use their psionic powers. Thus, while primarily designed to suppress telepathic abilities, psi-blockers also inhibit the use of other psionic skills, as long as the person trying to use those powers is with the blocker's area of effect.
A psi blocker's normal radius of effect is 2 meters. Superb and Legendary units have larger radii.
A person using a psi blocker suffers a -1 modifier to all Perception rolls.
Psi Blockers block all telepathy and telepathy related skills, but not other psionic skills such as psychokinesis. Other psionic skills are done at a -2 modifier when the user is within the range of an active psi-blocker.