Modern conveniences like the automobile and electricity were unfamiliar to him at young age, but he got into engineering anyway, thanks in large part to a natural curiosity that drew Spencer to the mills that populated the region.
At 12 he got a job at the spool mill one town over. At 14 Spencer got hired to install electricity at the nearby paper mill. A few years later he was so inspired by the heroic actions of the Titanic's radio operators that he joined the Navy and learned the new technology. Spencer would later explain, "I just got hold of a lot of textbooks and taught myself while I was standing watch at night.
After World War I, Spencer landed a job at the newly-established American Appliance Company , co-founded by engineer Vannevar Bush , who today is most known for organizing the Manhattan Project and predicting many of the innovations that led to the computer revolution and the internet.
In , the company changed its name to Raytheon Manufacturing Company. It's still around today making missiles , military training systems and electronic warfare products. In the '20's, Spencer became one of Raytheon's most valued and well-known engineers. During World War II, while Raytheon was working on improving radar technology for Allied forces, Spencer was the company's go-to problem solver. For example, he helped to develop proximity fuses, or detonators that allowed you to trigger artillery shells so they'd explode in mid-air prior to hitting their mark.
In an email to Popular Mechanics, current Raytheon engineer and part-time company historian Chet Michalak says Spencer "had a knack for finding simple solutions to manufacturing problems. Spencer earned several patents while working on more efficient and effective ways to mass-produce radar magnetrons. A radar magnetron is a sort of electric whistle that instead of creating vibrating sound creates vibrating electromagnetic waves.
According to Michalak, at the time Spencer was trying to improve the power level of the magnetron tubes to be used in radar sets. There were theories that high-frequency electric fields could be used for heating as early as but this method used frequencies that are lower than those of microwaves.
Between and , British physicist Sir John Turton Randall, together with a team of British coworkers, developed multi-cavity magnetron which allowed for production of electromagnetic waves of a small enough wavelength microwaves and development of radar.
Magnetron was given to the U. One of the companies that were given contract by U. In , he was working on powered radar set when he noticed that a chocolate bar that he had in his pocket was melting.
He exposed popcorns to microwaves and they popped, he tried the whole egg and it exploded. Then he attached a high density electromagnetic field generator to an enclosed metal box and experimented on food that way which allowed for controlled and safe experimentation. Microwave cooking oven was patented on October 8, with the one of the first prototypes placed at a Boston restaurant for testing. I decided to disassemble the HX into modules: The rotor bank lifted off, then the printer.
The base contains the keyboard, power supply, and controls. These snubbers had disintegrated. Also, the foam disks that ink the alphabet wheels were decomposing, and gooey bits were clogging the alphabet wheels. I made some happy, serendipitous finds. To rebuild the broken printer parts, I needed a dense rubber tube.
I discovered that a widely available neoprene vacuum hose worked perfectly. Using a drill press and a steel rod as a mandrel, I cut the hose into precise, millimeter sections.
But the space deep within the printer, where the plastic snubbers are supposed to be, was blocked by many shafts and levers, which seemed too risky to remove and replace. So I used right-angle long-nosed pliers and dental tools to maneuver the new snubbers under the mechanism. After hours of deft surgery, I managed to install the snubbers. The HX has nine rotors and also uses a technique called reinjection. Each rotor has a set of conductors that connect each and every electrical contact on one side of the rotor with a different contact on the other side.
For every rotor the pattern of these connections is unique. When the operator strikes a key on the keyboard, representing one of 26 letters, current travels through the set of nine rotors twice, once in each direction, and then through a separate set of 15 rotor contacts at least two times. This reinjection technique greatly increases the complexity of the cipher. The ink wheels were made of an unusual porous foam.
I tested many replacement materials, settling finally on a dense blue foam cylinder. Alas, it had a smooth, closed-cell surface that would not absorb ink, so I abraded the surface with rough sandpaper. After a few more such fixes, I faced just one more snafu: a bad paper-tape jam.
I had loaded a new roll of paper tape, but I did not realize that this roll had a slightly smaller core. The tape seized, tore, and jammed under the alphabet wheels, deeply buried and inaccessible.
I was stymied—but then made a wonderful discovery. The HX came with thin stainless-steel strips with serrated edges designed specifically to extract jammed paper tape. I finally cleared the jam, and the restoration was complete. One of the reasons why the HX was so fiendishly secure was a technique called reinjection, which increased its security exponentially. Rotors typically have a position for each letter of the alphabet they're designed to encrypt.
So a typical rotor for English would have 26 positions. But the HX's rotors have 41 positions. That's because reinjection also called reentry uses extra circuit paths beyond those for the letters of the alphabet. In the HX, there are 15 additional paths. Here's how reinjection worked in the HX In encryption mode, current travels in one direction through all the rotors, each introducing a unique permutation.
After exiting the last rotor, the current loops back through that same rotor to travel back through all the rotors in the opposite direction. However, as the current travels back through the rotors, it follows a different route, through the 15 additional circuit paths set aside for this purpose.
The exact path depends not only on the wiring of the rotors but also on the positions of the 41 modificators. So the total number of possible circuit configurations is 26! And each of the nine rotors' internal connections can be rewired in 26!
In addition, the incrementing of the rotors is controlled by a series of 41 mechanical pins. Put it all together and the total number of different key combinations is around 10 Such a complex cipher was not only unbreakable in the s, it would be extremely difficult to crack even today. Small, at the U. Army's Signal Intelligence Service. It was the subject of a secret patent that Small filed in and that was finally granted in No. Meanwhile, in , Hagelin applied for a U.
Perhaps surprisingly, given that the technique was already the subject of a patent application by Small, Hagelin was granted his patent in No. Friedman, for his part, had been alarmed all along by Hagelin's use of reinjection, because the technique had been used in a whole series of vitally important U. Friedman Collection. After a career as an electrical engineer and inventor, author Jon D.
Paul now researches, writes, and lectures on the history of digital technology, especially encryption. In the s he began collecting vintage electronic instruments, such as the Tektronix oscilloscopes and Hewlett-Packard spectrum analyzers seen here. The revelation of Crypto AG's secret deals with U. Nor are Apple Macs safe. Malware that allowed attackers to take control of a Mac has circulated from time to time; a notable example was Backdoor. Eleanor, around And in late , the cybersecurity company FireEye disclosed that malware had opened up a backdoor in the SolarWinds Orion platform, used in supply-chain and government servers.
The full extent of the damage is still unknown. The HX machine I restored now works about as well as it did in I have yet to tire of the teletype-like motor sound and the clack-clack of the keyboard. Although I never realized my adolescent dream of being a secret agent, I am delighted by this little glimmer of that long-ago, glamorous world. And there's even a postscript. Dawson did receive one microwave-related patent, 2,, , for a modification of the magnetron itself, really nothing to do with cooking.
No other US patents were issued to the others mentioned in this timeframe. Using 2. However, the engineer that reduced the idea to practice, and developed the first practical, commercially viable microwave oven known as the Radarange, was Marvin Bock. Some details of his life:. Death: March 27, , Santa Barbara, California. Electronic Engineer, 29 years with Raytheon. My dear father, Marvin J. Marvin was a quiet man with a profound sense of integrity.
He was an engineer not a manager and was never concerned about his name being on the door. He wanted to be in his laboratory and design systems. I heard that he was very proud of the work he did developing radar equipment for battleships.
Until recently I did not understand why he did not pursue his own recognition but I have come to believe that his development of the microwave oven was just not the important invention for him. He went to the World's Fair in Montreal to "present the oven to the world" and died 4 years later, not really having a sense of the importance of the oven. We had the original microwave in our garage in Needham when I was born in and I have the silver "Radarange" name plate from that oven.
From what I read in articles, in Marvin was appointed head of the microwave heating laboratory at Waltham. In he was named assistant head of the radio frequency and antenna department of Raytheon's Missile Systems Laboratory at Waltham and this is where his focus turned to the Sparrow and Hawk missiles. We moved to Santa Barbara in This is shown in Fig.
Note that it was a free standing white-enameled unit operating from V.
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