Use a Mel Meter:
Want to ghost hunt like a pro?
The Mel Meter is one of the most important modern tools any ghost hunter can carry. There are many different models of Mel Meters with varying features. This Mel Meter allows the user to measure both EMF and temperatures.
The Mel Meter is one of my favorite devices to ghost hunt with. It is easy to use, has a nice digital readout, and the back light really comes in handy out in the field during late night hours. The Mel Meter comes with a DC input or can also take a 9 volt battery.