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Empire of the Air

Responding to an article about vacuum tubes reader Phil Matthews suggested the book "Empire of the Air" by Tom Lewis. It's out of print but a used copy cost a whopping $0.21 (plus shipping). Though subtitled "The Men Who Made Radio," that's not really what the book is about. Some reviewers on complain that many important contributors were left out, which is true. Empire of the Air is really about Lee De Forest, Edwin Armstrong, David Sarnoff, and the RCA Corporation. Others are mentioned in greater or lesser detail.

The author starts the story mostly with Marconi's experiments giving occasional nods to Maxwell and Hertz. His technology pre-dated electronics: radio signals were created by a spark gap feeding energy into a tuned circuit.

In 1906 De Forest produced his Audion, reputedly the first triode, which was used as a detector, then an amplifier, and finally a transmitter.

A better circuit was needed and in 1913 Armstrong patented the regenerative receiver. This produced very high gain and immediately caught on. As a result of the invention Armstrong was soon a millionaire.

De Forest studied Armstrong's invention and then filed substantially the same circuits with the patent office starting a long-running dispute between the inventors. Armstrong humiliated De Forest in court when he showed the latter didn't understand how even the Audion worked. De Forest started scores of companies, some of which seemed more schemes to bilk investors rather than going concerns.

Armstrong went on to invent the superregenerative receiver. In the middle of WWI Major Armstrong (the only one of the three to serve during that conflict) invented the superheterodyne receiver, which is, even today, fundamental to radio engineering.

After over a decade of work he invented the FM radio. During WWII he worked on RADAR and other marvels. Armstrong was probably the most important of the early EEs. As the book makes clear, unlike De Forest, he patiently learned everything about a field before making a leap forward.

De Forest was more a dabbler than an engineer.

Sarnoff came to the US as a youngster in poverty and had little schooling. He was a voracious learner, though, and mastered the telegraph, soon becoming a telegrapher for Marconi. When the Titanic went down, well, we're not entirely sure what he did, but he later burnished his legend by claiming to be in contact with the ship throughout the ordeal. Sarnoff comes across as an unlikeable and driven character who ruled RCA with an iron fist. He was a bit of a visionary, in that at great expense he hitched the company's star to TV long before there was any reason to think it was a workable idea. The book claims that at his doing RCA invested $100 million in developing that technology, which would be billions in today's dollars.

There are technical errors in the book that will be apparent to any EE. They grate, but don't take away from the story.

A lot – a lot! - of the story is about the endless patent wars waged between the three principals.

Don't read the book if litigation repulses you. De Forest and Armstrong fed the lawyers most of their lives, battling each other, RCA, and a host of others. After decades involving 13 courts and 33 judges Armstrong lost the regenerative patents to De Forest. Why? De Forest did have one schematic that purported to show regeneration which pre-dated Armstrong's patents. But he didn't understand how it worked, and the judges judged not too judiciously.

Armstrong lost his superregenerative patents to another inventor. Even his superheterodyne claims were found to have been anticipated. When he died his FM patents were tied up in court.

De Forest felt from early on that he would be a Great Man, in part waging his legal battles to prove that to be the case. Later in life he worked hard on self-promotional PR, even inciting his fourth wife to start a never-finished tome called "I Married a Genius." Despite forming uncountable companies he died almost broke.

Sarnoff, too, later in life worked hard to embellish his reputation, pestering the government and others for countless awards. He was a serial philanderer who kept an apartment for his assignations, though remained married to his one and only wife till he died, a considerably wealthy man.

Armstrong was a stoic with little sense of humor and one wonders what sort of quality of life. He was happiest in the lab, miserable in litigation. There's no sense of any moral failings. But much moral outrage; he saw right and wrong and nothing in between, which was one of the drivers of his legal battles. Those wore him down and at age 54 he jumped from his 13th floor apartment.

The story ends with Marion Armstrong, who continued to pursue the FM patent litigation. Eventually she won every dispute. If only Edwin could have lived to finally see one of his great inventions vindicated in the courts! She collected royalties for years afterwards.

The book had me constantly going to the Internet to access other information; when I read De Forest had been on the TV program "This is Your Life," I found a YouTube video of that episode. At about 84 he is in serious decline, which is sad, and the Audion the host claims as the original doesn't look like the pictures I've seen of it.

Ironically, De Forest hated TV. He thought the programming on it and on radio completely banal and didn't fulfil his wish for uplifting content. And that was before the Kardashians and Celebrity Wife Swap. Armstrong couldn't be bothered to listen to radio as he was always busy working on inventions. Sarnoff was a workaholic who didn't even own one.

I couldn't put the book down. It's very readable and not at all technical (drats). But there are plenty of other sources for technical content.


Published August, 2016