Didn't know what to call this, but what I'm looking for is a small device I can operate remotely that can signal the greeter person at the haunt entrance that she or he can let the next group of guests in. I am busy in the control room and when the guests get past a certain gate in the haunt I want to be able to signal the 'green light' to the person at the entrance....if that makes any sense. Last time I tried using one of those remote activated halloween sound devices which I had lying around but the problem was it started going off spontaneously and we got a flood of guests entering when we weren't prepared! So a friend of mine had a pair of 2-way hand-held devices but these were very cumbersome. I need something very simple and inexpensive. Any ideas?