There are many people using technology today without a clear understanding of how it works. I recently saw a video of a ghost hunting team that was in my area, and I recognized where they were shooting. Specifically what they were demonstrating was EVP (Electronic Voice Phenomenon). This is when an unexplained voice is caught on an audio recording device. Many people believe this to be evidence of ghosts, but we live in a world of devices that leak energy in various forms and under certain circumstances, devices can interact in a manner that was unexpected. An audio device can sometimes pick up a radio signal. What I knew about the location that this group picked was that even though they showed the old WWII buildings in the video, directly behind the camera operator was the Marine Exchange, and their radio tower. My video shows this.
Additional footage showed them using a phone as an audio recorder and holding an EMF (Electromagnetic Field) meter next to it. They commented on how every time they talked, the EMF meter would jump. The problem is the voice recognition on the phone is not processed locally on the phone. Every time the phone hears something that needs to be interpreted into a command, that data has to be sent out for voice recognition processing which explains the jump on the EMF meter when the phone transmits the voice signal to the processing center. EMF meters are not frequency specific, and therefore of limited use. In my own tests I used a Spectrum Analyzer to be able to identify what type of energy was being detected.
There are mysteries out there, but using equipment improperly will not uncover them.