ITC stands for Instrumental Trans Communication. The ITC theory states that a ghost/spirit will use different environmental conditions such as EMF (electro magnetic fields), RF (radio frequencies), static electricity, and microwaves, to communicate with us in real time.
Be aware when using these types of devices that you are using a device that may be able to pick up radio waves and therefore can interfere with your evidence.
Listed below are some of the devices used in testing this theory:
Echo Vox P-SB7 Spirit Box
Ovilus IV Paranormal Puck