I rapidly pressed the fast forward and reverse buttons on a little cassette recorder while it was playing an old radio show from the 90s. One of the first fx recordings i ever did. Recorded with a samson c03u microphone, no processing.
My ghost meter signals a change in emf which is a sign of paranormal activity. Slow individual beeps along with very fast beeps signal strong activity. Useful for paranormal investigation-type videos or podcasts.