Currents of the Past

From publisher blurb:

"Currents of the Past" is a creepy adventure set in 1901 in present-day Latvia, which was then part of Tsarist Russia. August Peter von Uexküll, a German-Baltic nobleman and inventor, invites the player characters to his country estate, where he wants to demonstrate wireless voice transmission with the help of a radio wave device. Once there, strange incidents occur, and it's up to the player characters to get to the bottom of things.

The adventure describes backgrounds, locations, NPCs and possible scenes, and comes with eight ready-made characters. Stats are given as % to be used in other systems that use them and can easily be converted to other systems.