In a post by Hawker40:
This is a fighter pilot story, so you know it's true.
Raytheon is the designer/builder of the AIM-9 "Sidewinder" air to air missile, best anti-air weapon ever. Sidewinders are heat-seekers, 'locking on' to the aircraft's hot engine exhaust In theory. Early (1950s) versions of the missile had the bad habit of locking on to the hottest thing in it's field of view. If a dogfighting aircraft pointed the nose at the sun, the missile would lock on to the sun, and then refuse to accept anything colder as a target. So, your missile tells you it's locked on to a target, you pull the trigger, and the missile goes screaming skyward trying to kill the sun. (Ignoring any enemy planes in the area to do so.)
To solve the problem, Raytheon came up with the "Break Lock" button, claiming that by pressing a button installed in the cockpit the missile would lose any lock on it had and look for a new target. It worked by the simple expedient of turning the missile off and back on again. Raytheon had invented the reset button decades before Apple or IBM had put them on computers.
So, to fighter pilots (and Navy firecontrolmen), to try to fix something by turning it off and immediately back on is a "Raytheon Reset".