Monday, August 31. 2009
The FCC has announced plans to investigate the wireless industry ("Fostering Innovation and Investment in the Wireless Communications Market").
The Competitive Enterprise Institute responds:
"The wireless industry is the last place regulators should be looking for alleged anti-competitive behavior. The wireless market is intensely competitive, and consumers enjoy a dizzying array of competing mobile platforms and service arrangements," said Ryan Radia, Information Policy Analyst. "Consumers looking for a mobile handset can select from the open source HTC G1 to the walled-off iPhone, and everything in between. In addition, practically every big wireless provider offers both long-term and month-to-month service options. Where is the anti-competitive behavior?"
Saturday, August 29. 2009
This post is the eighth in a series based on my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, published in 2008. Each week I’ll present the most interesting and surprising facts about the history and future of wireless from one of fourteen chapters.
Why I Miss Vacuum Tubes
The vacuum tube triode was one of the greatest inventions ever. It didn’t abrogate the laws of physics, but it certainly delivered more for less. It was to electronics what the lever, wheel, and screw were to mechanics. It became a ubiquitous building block, often serving multiple purposes at the same time, and it enabled a torrent of inventions.
In laymen’s terms, the vacuum tube transmitter produced beautiful continuous waves, added voice or music, and boosted the signal so it could be heard far away. The vacuum tube receiver picked up weak signals, extracted the speech or music, and made the audio loud.
When I was growing up the vacuum tube was still king. I’ll never forget earning my first ham radio license and building a crystal-controlled, 40-watt transmitter out of parts salvaged from old TVs. I started with a piece of sheet metal, drilled holes for the sockets and switches, and bent the metal into the shape of a chassis. I mounted the parts and soldered the wires. It seemed to work—at least on the workbench. Yet it was hard for me to believe this little contraption could produce CW (Morse code) signals that would be heard 1,000 miles away.
I hooked it up to my antenna and nervously began tapping out “CQ”—the Morse code abbreviation for “calling anyone.” An hour of trying yielded no responses. Was my 4-tube Hallicrafters receiver the problem? Or was my ground-mounted vertical antenna too close to the house? Then I heard someone tapping out my call sign. My first contact was a station in Maryland. (I was living in a suburb of Chicago at the time.) I was thrilled.
Transistors were already starting to replace vacuum tubes. My next “rig” was a kit consisting of both vacuum tubes and transistors. But the writing was on the wall: the vacuum tube was doomed by computers. Vacuum tubes were too big, too power hungry, and too unreliable. Heck, so were discrete transistors. It wasn’t long before they were replaced by integrated circuits.
It’s not the vacuum tubes themselves that I miss. It’s building, troubleshooting, and operating my own equipment. I somehow felt more “connected” to the technology.
The eighth chapter of my book is about Lee de Forest, inventor of the vacuum tube triode, and Edwin H. Armstrong, inventor of the regenerative receiver, the superheterodyne receiver, and frequency modulation--all using vacuum tubes. It’s an inspiring story in many ways, but it’s also a tragedy.
Armstrong learned early on that most people are their own worst enemy. Paraphrasing American humorist Josh Billings, Armstrong’s mantra became: "It ain't ignorance that causes all the trouble in this world. It's the things people know that ain't so." As if to illustrate the point, Armstrong invented frequency modulation (FM) after a respected Bell Labs engineer announced that it wasn’t worth doing. Everyone assumed from the start that FM had to be a narrowband technology. Armstrong discovered FM’s crystal clear audio by ignoring conventional wisdom.
Unfortunately, Armstrong got embroiled in patent disputes that he probably could have avoided. After a string of defeats in court, the man who used to get a thrill climbing antenna towers jumped out of his 13th story window to his death. Ironically, his wife (who had tried to dissuade him from continuing the patent fight) took up the cause and managed to overturn two major court decisions, vindicating her late husband.
Next time: David Sarnoff—high tech business genius or SOB?
Friday, August 21. 2009
This post is the seventh in a series based on my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, published in 2008. Each week I’ll present the most interesting and surprising facts about the history and future of wireless from one of fourteen chapters.
The Amazing Reginald Fessenden
Reginald Aubrey Fessenden was a prolific inventor. His creations ran the gamut from microfilm to sonar to the turbo-electric drive for battleships. His wireless innovations, however, were simply visionary. In Canada, the centenary of the first audio broadcast was celebrated with a postage stamp honoring Fessenden.
Fessenden recognized that the technology used by Guglielmo Marconi, spark radio, had severe limitations. Sparks are inefficient, invite interference, and are ill-suited to carry speech. Fessenden knew exactly what the problem was, and it wasn’t long before he conceived a solution.
Fessenden envisioned a simpler and cleaner technology. He knew that if he could produce steady electromagnetic waves—the kind represented mathematically as pure sine waves—he could boost efficiency, reduce interference, and impress the signals with speech and music. Fessenden’s pristine signals became known as “continuous waves.”
Reginald Fessenden could be called the Alexander Graham Bell of wireless. He was first to demonstrate the transmission of voice and music over wireless. He also invented a variable detector (for receiving audio) and the heterodyne principle (enabling easy-to-use receivers for consumers).
Unfortunately, Fessenden was at least ten years ahead of his time. He tried to create continuous waves by building AC power generators rotating at extraordinarily high speeds. Once Edwin H. Armstrong discovered that a vacuum tube amplifier could be made to oscillate using feedback, it became possible to replace Fessenden’s giant, mechanical generators with small, inexpensive boxes that could run at even higher frequencies and required no moving parts.
Fessenden’s business accomplishments, however, never came close to matching his technical achievements. Consequently, he received neither the fame nor fortune that the quality of his work should have commanded. His mother was adamantly opposed to his becoming an inventor because her father had traveled the same road and left his family in poverty when he died. That may explain why Fessenden hesitated, wasting years looking for someone to hire him on safe terms. He wanted to pursue his own inventions, but he also wanted a steady salary. When he finally started his own business, he hedged his bets, pursuing both spark radio and continuous wave products, believing all the while that the former was racing towards obsolescence. He would have been better off pursuing the two leading continuous wave technologies simultaneously, never missing an opportunity to promote continuous waves, and doubling his chances of being in the right place at the right time.
Reginald Fessenden kept making compromises. Instead, he should have followed his passion.
Next time: Diodes and Triodes and… Patent Wars
Friday, August 14. 2009
This post is the sixth in a series based on my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, published in 2008. Each week I’ll present the most interesting and surprising facts about the history and future of wireless from one of fourteen chapters.
There are three things you should know about Guglielmo Marconi: (1) He was a business visionary more than an inventor, (2) he bet on a technology that ultimately proved a dead end, and (3) Marconi dominated the early market but was forced (by the U.S. government) to sell Marconi America before radio broadcasting took off.
Scientists could observe Hertz’s invisible electromagnetic waves for themselves; his experiments were simple and repeatable. They could also see that Maxwell’s theory of the electromagnetic field correctly predicted the waves. But they still could not envision practical applications for Hertzian waves.
Ironically, Marconi succeeded because he could see markets that did not yet exist, but when a better technology (continuous wave radio) emerged he was slow to abandon his trusted spark radio.
Next time: How Reginald Fessenden Put Wireless on the Right Technological Footing
Saturday, August 8. 2009
This post is the fifth in a series based on my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, published in 2008. Each week I’ll present the most interesting and surprising facts about the history and future of wireless from one of fourteen chapters.
Wireless: the “Horseless Carriage” of Telecommunications
To understand wireless, we must first understand the wired foundation that inspired it. Here we meet two of the greatest technology entrepreneurs in history: Samuel F.B. Morse, inventor of the electric telegraph, and Alexander Graham Bell, inventor of the telephone.
Even today there are people who will tell you that Morse did not invent the telegraph; that Bell did not invent the telephone; and that Marconi did not invent wireless. They have a point: there is evidence in each case that someone else conceived the invention first. However, it’s not enough to think up an invention or even build a prototype first. You have to convince others.
Morse is the easiest to dismiss. The man was an artist. He was not an expert on electromagnetism. But he believed that people would welcome faster communications between towns once they witnessed its power and convenience. Roughly twelve years from the time Morse first began working on the telegraph, the first trial telegraph service was introduced between Washington, DC and Baltimore.
Others demonstrated working telegraphs earlier. One scheme required a separate wire for each letter in the alphabet. The British inventor Charles Wheatstone came up with a clever system that could handle the entire alphabet using just six wires. Morse understood the need for a simple, reliable, and affordable system. He invented a sort of digital code making it possible to transmit and receive the entire alphabet with just two wires. He also invented an automatic relay that enabled him to construct lines of almost any length.
Creation of the first working undersea telegraph cable by Cyrus W. Field (Morse served briefly as an advisor) led to what author Tom Standage dubbed the “Victorian Internet.”
Morse proved that it is possible to convey intelligence over wires using electricity. However, it all boiled down to turning the electric current off and on according to a set of rules (a code). No one knew if it was possible to send human voices over the wires.
Alexander Graham Bell set out to develop a way to send more than one message over a telegraph circuit at the same time—what was called the “multiple telegraph.” He was soon attracted to the idea of sending different messages at different frequencies. He gradually realized that if you can send tones of different frequencies at the same time, then you should be able to transmit human voices.
Like Morse, Bell not only developed a simple solution, he convinced others it was worth the trouble. And like Morse, he spent years fending off unscrupulous individuals who suddenly remembered that they had invented it first. I call them “retroactive inventors.”
Next time: Marconi’s Thunder
Saturday, August 1. 2009
This post is the fourth in a series based on my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, published in 2008. Each week I’ll present the most interesting and surprising facts about the history and future of wireless from one of fourteen chapters.
The Wave Makers
Who was first to demonstrate radio waves? The German physicist Heinrich Hertz gets official credit, but the English physicist Oliver Lodge proved Maxwell’s theory at around the same time. Why one became internationally famous practically over night and the other only earned an honorable mention is a fascinating story.
Hertz declined the challenge by Hermann von Helmholtz, the dean of German science, to prove an obscure but crucial aspect of Maxwell’s theory (displacement current). Hertz’s explanation at the time was that he did not know enough about Maxwell’s theory and, in any event, could not think of any relevant experiments.
Then Hertz observed an unexpected but subtle phenomenon while preparing a demonstration for his students. It wasn’t long before he demonstrated radio waves—proving Maxwell’s theory—and discovered the photoelectric effect to boot in the process.
Hertz set out to teach his students about electric induction. (Today, induction is used for purposes such as stepping down 110 volts from a power outlet to 12 volts.) In the school’s laboratory he found a couple of heavy wire coils that terminated in spark gaps and immediately realized they could be used to provide a visual demonstration. A surge of electricity in the first coil would cause it to spark and induce a sufficient current in the second coil to make it spark, too. But when he tried it he was surprised at how easy it was to make the second coil spark. He suspected something other than induction was at work.
He straightened out the first coil but kept the spark gap; in place of the second coil, he used a ring of heavy wire that didn’t quite make a full circle (creating another spark gap). He found he could “induce” a spark in the wire ring even from across the room. As he moved the ring further away, the size of the sparks might increase, then decrease, and then increase again—suggesting he was observing the peaks and nulls of a wave. To better see the sparks, he sometimes placed the ring in a wooden box with a little window. He noticed the sparks were smaller in the darkened box and concluded that light affected the size of the sparks, as well.
After months of experimenting, he knew that he had proved Maxwell’s theory, and published a paper that caused an immediate sensation. Ironically, when asked by newspaper reporters about the waves, Hertz assured them it was just an interesting phenomenon with no practical applications.
Oliver Lodge was also a talented physicist, but he seemed to have a knack for coming up short. He did an experiment that involved discharging a Leyden jar and produced peaks and nulls along a long wire. Satisfied his experiments proved Maxwell’s theory he promptly left on vacation, figuring there would be plenty of time to publish when he got back. He returned to hear the news that Hertz had beat him to the punch. (Later, he realized that the wire only served to guide the waves; it would have been a more dramatic experiment without the wire.)
Lodge also demonstrated wireless signaling before Marconi but neglected to use Morse code. Then Lodge invented a method for dividing the radio spectrum into different frequency channels—what he called “syntony” and we now call "channel surfing." This time he was smart: he patented his invention and eventually sold the rights to Marconi.
Though Lodge did not think it would ever be possible to communicate across the Atlantic Ocean using radio waves, he did believe it is possible to communicate with the dead.
Next time: How Morse and Bell Invented Wire Communications--Setting the Stage for Wireless
(Page 1 of 1, totaling 6 entries)
Syndicate This Blog