Five Infernal Devices For Your Old School Horror Campaigns

1. The Talhoursor Device - This strange amaglam of gears, electronics, and tubes draws it energies from the Outer Void. When activated by the primitive set of switches. The device creates a field of loose gravity waves in the form of a bubble. The device causes all who are within the 20 foot radius of the field of the device to react as if subject to a spell of true seeing. The device itself weights 27 pounds and enables those within its field to be able to cross into nearby dimensional space. There is a 30% chance of a random planar demon spotting those within the field and following them with the intent of killing and eating them later. 
2. The Browning Instrument - This odd musical instrument is a wood wind flute type device with a strange ivory coloured end. The device once played will draw "things" from the nearby astral. These might be anything from a demon to an elder god. The user must continue to play the device lest the monster cross the dimensional fold. The device may also summon 1d8 ghosts from the nearby realms of the dead. These ghosts are free willed and there is a 40% of a specter or ghost being within the the midst of the dead who hover around this device. 
3. Tesla's Golden Coil - This dimensional powered gate way leads to hundreds of worlds. The device only a one way trip and trap for those who use nasty device. The golden coil can easily beam any energy weapon discharge to any point in the known universe. The device is only good enough for eight jumps before burnout and in need of a replacement part. The device also has a separate observer from the Great Race who may recruit the character or PCs for an assignment. They may use the device to kidnap a character from any point in history. 
4. The Demon Engine - This amalgam of demon and human flesh shot through with electronics and wires. The engine can be used for a one way trip into the Abyss. The engine once its turned on will summon 1d8 demons per round. There isn't any way of shutting this thing down. More demons will arrive all the time and over run the PCs if possible. The engine will also make the general populace react in fear to anyone exposed to the fumes from the engine. 
5. The Clock work of Trow - This device is a collection of golden gears created from the gathered tears of angels. The device summons 1d6  angels and the host that comes with them. The clock work will also spout off a prophecy that has a 10% chance of accuracy. Should the device be monkeyed with it will sumon 1d4 angels to deal with PCS. The device is often found in the middle of important happenings and battles waiting for some fool to activate it.