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Maxed Out: Two Longs and a Short
May 16, 2012 |Estimated reading time: 8 minutes
You may recall my meandering musings a few columns ago about the telephones and televisions of yesteryear. Well, you would not believe how many e-mails I have received from folks who have their own memories of those days or yore. For example, Bob Landman sent the following message from his iPhone:
Hi Max. Your articles on the good old days were great fun to read. I started in electronics when I was ~12 back in 1955. Built kits, starting with the famous Philmore Junior crystal (radio) set. Then Heathkits and EICO test equipment so I could make some money repairing family and friends’ radios, phonographs, wire and tape audio recorders and eventually TV sets. (Color TVs had metal body CRTs and the anode voltage was 24kV which, if you forgot to discharge would give you a hell of a shock!)
Progressed to scratch-built stuff like a one-tube (valve to you) super-regenerative shortwave receiver with a 6SN7 tube.
I never had a job that wasn't in the electronics industry. When I graduated from high school, that summer before college, I was a test technician on a production line making carrier telephone equipment for small independent phone companies.
I subscribed to many trade journals and in one of them (telco industry) appeared the story "Two Longs and a Short.” I found a copy on the net for you. It’s a gem :-)
And now I sit here, a mere 56 years later and type on a tiny flat digital screen, to send you electronic mail!
Cheers!
Bob Landman
Bob provided a link to his article Two Longs and a Short. This describes a time when party lines were common. The idea was that multiple customers were connected to the same local loop; prior to WW II, party lines were the primary way residential subscribers acquired local telephone service in America.
The problem, of course, is how would you know that a call was intended for you and not your neighbor? Well, you have to remember that at that time you didn’t direct dial your target number. Instead, you called the operator, who then called the house for you. So the operator would use different rings for each house. One home might be a short ring followed by a long ring; another might be two shorts and a long; and yet another might be two longs and a short. You also got a very personal service in those days, as you will see by reading Bob’s article.
A Sight You’ll Never see Again
I don’t know about you, but I am endlessly fascinated by things like solar and lunar eclipses. So I was really interested to hear that there will be a transit of Venus on June 5 or 6, 2012, depending on where you live in the world (observers in North America will see it on June 5).
During the transit of Venus, the planet passes directly between the Earth and the sun, and we see it as a small dot passing across the face of the sun. This is a really rare event. It actually occurs in a pattern that repeats every 243 years, with pairs of transits eight years apart separated by long gaps of 121.5 years and 105.5 years. The one on June 5 will be the last of the current pair. The previous pair occurred in December 1874 and December 1882; the next pair won’t come around until December 2117 and December 2125, which means that this is the last chance in our lifetimes.
Of course you must NOT look directly at the sun, because doing so can result in serious, sometimes permanent damage to the eye. One option is to use a telescope to project an image of the sun onto a piece of paper. The other is to use special eyeglasses.
I opted for the eyeglasses. In fact, since they are so cheap – and since this will be an occasion to remember – I splashed out on 25 pairs to share with family and friends. You can get this type of thing all over the place, but you do want to make sure they are “legit” and will do the job. The cheapest I’ve found so far is from Woodland Hills Telescopes at $0.95 each, falling to $0.85 for 25 pairs, with bigger price breaks the more you buy.
One reason I really like these glasses (in addition to the fact that they make me look really cool and trendy of course) is that all proceeds from the sale of these glasses go to support programs by Astronomers Without Borders, an organization that, according to its mission statement, “…fosters understanding and goodwill across national and cultural boundaries by creating relationships through the universal appeal of astronomy.”And you can’t argue with a mission like that!
Ex Libris Maximus
The fact that there is to be a transit of Venus in just a few short weeks reminded me of a book I read last year – The Age of Wonder by Richard Holmes. This is a really great history of the men and women whose discoveries and inventions in the late 1700s and early 1800s gave birth to the Romantic Age of Science. As fate would have it, the first chapter of this book is devoted to the first scientific expedition, led by Captain Cook, to view a transit of Venus. I really enjoyed this book, and would heartily recommend it.
Unfortunately, I cannot say the same for Turing's Cathedral: The Origins of the Digital Universe by George Dyson. I think I was expecting a biography of Alan Turing, whose work helped kick-start the modern computer age. Although Turing does receive a few good mentions, this book is more of a description of the pioneering development of computing in America during the decade after World War II. Personally I like reading about computer history, and I did learn a lot from this book, so on this basis I’m glad I read it. On the downside, the writing was really hard to get through – somehow the author managed to make interesting things sound boring, and make boring things sound even more boring. The bottom line is that I would NOT recommend this book unless you are really enthusiastic about learning lots of nitty-gritty details about the lives and characters of the early computer pioneers.
Other books I’ve read or re-read recently:
Shakespeare – The World as Stage by Bill Bryson. When I was in high school, the thought that I would one day read a book about Shakespeare for my own pleasure would have had me rolling on the floor laughing. But Bill Bryson’s skill is that he can write a book about the Bard that is incredibly informative … and still has me rolling on the floor laughing. Verdict: Highly recommended.
In Pursuit of the Unknown – 17 Equations That Changed the World by Ian Stewart. The author has a very friendly and engaging style, and he provides detailed explanations of things I may once have known, but (if so) have long forgotten. And even for the ones I remember, this book provides a lot of fascinating background. Some of the topics are easy – others make your eyes water. Overall I really enjoyed it. Verdict: Recommended.
Hacker's Delight by Henry S. Warren Jr. I should note that in the early days of computers, a hackerwas someone who delighted in subtle programming tricks and small algorithms that could be used to make their computer code “tighter” and more efficient. If you are into writing computer programs, then I think you will find this book to be very interesting. Verdict: Recommended.
Nine Algorithms That Changed the Futureby John MacCormick. This is a VERY interesting book. What the author has done is to focus on a small number of revolutionary algorithms that the vast majority of computer users come into contact with every day without even knowing it. The author employs simple analogies that we can all understand. His use of mixing colored paints to explain the machinations of public key cryptography is, frankly, brilliant. Verdict: Highly recommended.
Alone in the Universe: Why Our Planet is Unique by John Gribbin. Before reading this book, if you had asked me if there were other intelligent races in the universe I would have answered “Of course!” But after reading this book I’m not so sure. The bottom line is that I thoroughly enjoyed this book. I learned lots and lots of stuff and it’s given me a whole lot of things to think about. Verdict: Highly recommended.
Robopocalypse by Daniel H Wilson. In which we discover how self-aware computers could take over the world. Although this is a fictional book, I have to say that it is frankly more than a little scary. The author, Daniel H. Wilson, earned a Ph.D. in robotics from Carnegie Mellon University, and he knows what he’s talking about. The strange thing is that, just a few hours after I’d finished reading Robopocalypse, I turned on the television and found myself watching one of those “10 Ways the World Might End” type programs. You can only imagine my surprise to discover that our being wiped out by self-aware artificial intelligences is now rated about number six on the list. Verdict: Highly recommended.
The Artificial Ape by Timothy Taylor. The conventional understanding of the way humans evolved is that, sometime around 1.8 million years ago, for one reason or another, our ancient ancestors started to become more intelligent, which allowed us to start creating tools. As our intelligence increased, we continued to make more and more complex tools. In this book, the author turns this theory on its head by proposing that it was our first use of primitive tools (or use of found objects in the earliest days) that conveyed significant advantages that spurred us to develop increased intelligence, which allowed us to develop more sophisticated tools, which drove further increases in intelligence, and so it went. Verdict: Recommended.
Until Next Time
Since I typically read several books like those discussed above each week (this doesn’t include any science fiction and/or horror books I might read), I could go on for hours, but then we might have nothing to talk about next time (grin).
Speaking of which, until next time, have a good one!
Clive (Max) Maxfield is founder/consultant at Maxfield High-Tech Consulting. He is the author and co-author of a number of books, including Bebop to the Boolean Boogie (An Unconventional Guide to Electronics) and How Computers Do Math featuring the pedagogical and phantasmagorical virtual DIY Calculator. To contact Max, click here.