Sandy petersens cthulhu mythos 161

Artifacts
In the case of technological items, “artifact” refers to
an item that is beyond the means of anyone within
the campaign setting to create or replicate, as well as
beyond conventional measures of value. Unlike magical
artifacts, technological artifacts can be destroyed just
as other items can.

THE ULTRA-VIOLET RESONATOR
Weight 25 lbs.; Capacity 7 charges; Usage 1 charge

The Ultra-Violet Resonator summons 1d4 random
entities from other planes (as a summon monster IX
spell, but they can also be any creatures from Chapter
9) into its plane of existence, allowing the user to see
them, touch them, and communicate with them. The
entities remain for only 1d6 rounds, then return to
their proper plane of existence. The resonator recharges
1 charge per month.

No live organism can continue for long to exist sanely under conditions of
absolute reality; even larks and katydids are supposed, by some, to dream.
—Shirley Jackson, The Haunting of Hill House

154