He said once all the wiring is done and ready for the evening show, a panel of diodes is used to trigger the mortars. The wooden box containing the diodes “that looks like the game Operation” has each numbered diode hit with an electrified pen that sends a signal through the wires to fire a line of mortars. Set against a yellow background, the silver diodes count up to 500, but King said 399 cues will be struck, firing the shots. Last year, there were about 360 cues, King said.
If one of the diodes doesn’t fire or if it isn’t struck with the timed show or just plain skipped, King or one of the other employees will run out to the rows and manually zap the wires, or hit the fuse with a blowtorch.
The mortars range from about 3 inches in diameter to as much as 6 inches. With attendees sitting right next to the display in the stands at the field, anything larger could be dangerous, King said.