As the second referee, what signal should be used when the ball is passed outside the antenna?

When the ball is passed outside the antenna, the appropriate action is to signal that the ball is "out." This is because the ball must cross within the boundaries defined by the antenna to be considered in play. When it travels outside the antenna, it is no longer deemed valid according to the rules of volleyball, thus warranting a signal that indicates it is out of bounds. Understanding this is crucial for maintaining the flow of the game and ensuring proper officiating.

In contrast, signaling for "in" would be inappropriate in this scenario as the ball did not fall within the playing area. The signal for "touch" applies in situations where the ball touches a player before going out, which is not the case here. The signal for "replay" would indicate a situation in which the rally must be replayed, thus also not relevant when the ball clearly traveled outside the antenna.