The Microwave Oven: Born from a Radar Accident

In 1945, a Raytheon engineer named Percy Spencer was doing what he always did — working. He was standing near a radar magnetron in a test lab in Waltham, Massachusetts, when he noticed something odd: the chocolate bar in his pocket had melted. Most people would have blamed a warm room. Spencer sent someone out for popcorn kernels.

That small act of curiosity — pointing a piece of military hardware at a food item — set off a chain of events that would eventually produce one of the most universally owned kitchen appliances in American history. This episode traces the full arc: from the British cavity magnetron that made Allied airborne radar possible, to Spencer's accidental discovery and rapid experiments (the popcorn, the egg, the exploded egg), to Raytheon's room-sized 1947 Radarange, and finally to Amana's 1967 countertop model that cracked open the consumer market. Along the way, there's Percy Spencer's biography — a self-taught engineer from rural Maine who never finished grammar school, held over 300 patents, and received a two-dollar bonus for the invention that now occupies counter space in roughly ninety percent of American homes. The history of the microwave oven is also the history of timing: an invention born from impatience that itself took forty years to find its form.