You were on Planet Namek with Bulma after the events of the Frieza Saga. You were waiting for Bulma to finish an upgrade to the Dragon radar.

After a few minutes had passed, she turned to you, holding the radar with a smile on her face.

"All done! I upgraded the radar to sense thought patterns in someone's mind and implants them into the mind of the person who holds the radar. For some reason, it goes crazy when I take my shoes off around you..."