EMF reader tier 3 quetion

[Elias]

Is it possible a Ghost will activate the EMF reader without me being in the building?.
Im in the middle of the golden Apocalypse challenge and i dont have any smokies left to help me and i cant find the ghost room anymore because of that so i placed two random EMF readers on the ground. Is it possible for them to get signals while i hide in the truck?

I have the ghost the picture and the other two missions only the reader mission is left

[wely]

a

[Cool Cereal]

Emf readers will track nearby activity even if you’re not holding it. Not sure if the objective will be marked as completed though.

[Maya-Neko]

EMF-signals are always created when the ghost touches or throws something and the signal keeps there for 20 seconds on the interacted object.

When an EMF-Reader gets close to these signals it will react, no matter if you're holding the Reader or not, so yes, you can leave it near the ghost and wait until it does something. Though keep in mind, that the ghost can't just get to every room they want, since the ghost has a limited range, so you need to put the EMF-Reader close to it.

Now the ghost can roam and even change ghost room, so if the ghost is in the back of a wing, it might eventually be able to jump rooms over and over to get closer to it, but keep in mind, that ghosts have a limited roaming distance, so it's quite hard for them to get out of wings in particular due to how far the next room might be (particularly because they can't change their room into a hallway). It might also take a while, maybe even hours if you put it very far away (pretty much comes down to the distance and heavy RNG-luck)

Also Goryo and Banshee can't change ghost rooms, so if you've one of those, you've to get closer to them to put down the EMF-Reader, usually within 2 rooms of the ghost room.