PKE Meter
From Multiversal Omnipedia
The PKE Meter (Psychokinetic Energy Meter) was a device developed by the Ghostbusters that enabled them to detect supernatural energies. It was generally used, of course, to find ghosts, but other uses were found. The PKE Meter can detect ghosts of up to Class 10 level- anything in excess overloads and destroys the Meter.