The Flight That Made The Calculator And Changed The World

November 27, 2017 by Steven Dufresne 89 Comments

It was the fall of 1965 and Jack Kilby and Patrick Haggerty of Texas Instruments sat on a flight as Haggerty explained his idea for a calculator that could fit in the palm of a hand. This was a huge challenge since at that time calculators were the size of typewriters and plugged into wall sockets for their power. Kilby, who’d co-invented the integrated circuit just seven years earlier while at TI, lived to solve problems.

Fig. 2 from US 3,819,921 Miniature electronic calculator

By the time they landed, Kilby had decided they should come up with a calculator that could fit in your pocket, cost less than $100, and could add, subtract, multiply, divide and maybe do square roots. He chose the code name, Project Cal Tech, for this endeavor, which seemed logical as TI had previously had a Project MIT.

Rather than study how existing calculators worked, they decided to start from scratch. The task was broken into five parts: the keyboard, the memory, the processor, the power supply, and some form of output. The processing portion came down to a four-chip design, one more than was initially hoped for. The output was also tricky for the time. CRTs were out of the question, neon lights required too high a voltage and LEDs were still not bright enough. In the end, they developed a thermal printer that burned images into heat-sensitive paper.

Just over twelve months later, with the parts all spread out on a table, it quietly spat out correct answers. A patent application was filed resulting in US patent 3,819,921, Miniature electronic calculator, which outlined the basic design for all the calculators to follow. This, idea borne of a discussion on an airplane, was a pivotal moment that changed the way we teach every student, and brought the power of solid-state computing technology into everyday life.

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Can Commodity RC Controllers Stay Relevant?

November 20, 2017 by John Baichtal 42 Comments

Visualize some radio controlled airplane fanatic of yesteryear, with the requisite giant controller hanging from a strap, neck craned to see the buzzing dot silhouetted against the sky. It’s kind of a stereotype, isn’t it? Those big transmitters were heavy, expensive, and hard to modify, but that was just part of the challenge. Additionally, the form factor has to a degree remained rigid: the box with gimbals — or for the 3-channel controller, the pistol-grip with the big pot that looks like a cheesy race car wheel.

With so much changing in RC capabilities, and the rise of custom electronics across so many different applications, can commodity RC controllers stay relevant? We’re facing an age where the people who invest most heavily in RC equipment are also the ones most likely to want, and know how to work with customization for their rapidly evolving gear. It only makes sense that someone will rise up to satisfy that need.

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The Database Of The Time Lords

November 20, 2017 by Brian Benchoff 71 Comments

Time zones have been a necessity since humans could travel faster than a horse, but with computers, interconnected over a vast hive of information, a larger problem has emerged. How do you keep track of time zones? Moreover, how do you keep track of time zones throughout history?

Quick question. If it’s noon in Boston, what time is it in Phoenix? Well, Boston is in the Eastern time zone, there’s the Central time zone, and Phoenix is in the Mountain time zone; noon, eleven, ten. If it’s noon in Boston, it’s ten o’clock AM in Phoenix. Here’s a slightly harder question: if it’s noon in Boston, what time is it in Phoenix during Daylight Savings Time? Most of Arizona doesn’t observe Daylight Savings Time, so if it’s noon in Boston, it’s 9 AM in Phoenix. What about the Navajo Nation in the northwestern part of Arizona? Here, Daylight Savings Time is observed. You can’t even make a rule that all of Arizona is always on Mountain Standard Time.

Indiana is another example of bizarre time zones. For most of the 20th century, Indiana was firmly in the Central time zone. Starting in the 1960s, the line between Eastern and Central time slowly moved west from the Ohio border. Some countries opted not to observe Daylight Savings Time. In 2006, the entire state started to observe DST, but the northwest and southwest corners of the state remained firmly in the Central time zone. The odd geographic boundaries of time zones aren’t limited to the United States, either; Broken Hill, New South Wales, Australia is thirty minutes behind the rest of New South Wales.

Working out reliable answers to all of these questions is the domain of the Time Zone Database, a catalog of every time zone, time zone change, and every strange time-related political argument. It records Alaska’s transition from the Julian to the Gregorian calendar. It describes an argument in a small Michigan town in 1900. It’s used in Java, nearly every kind of Linux, hundreds of software packages, and at least a dozen of the servers and routers you’re using to read this right now.

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Organizing Teams With Collective Fictions

November 14, 2017 by Christian Trapp 38 Comments

There is often an observable difference between what is considered the right thing to do, and what actually is being done.

Terry Pratchett said it best when he made Death declare mercy and justice nonexistent: “TAKE THE UNIVERSE AND GRIND IT DOWN TO THE FINEST POWDER AND SIEVE IT THROUGH THE FINEST SIEVE AND THEN SHOW ME ONE ATOM OF JUSTICE, ONE MOLECULE OF MERCY.” (Note that Death is not shouting, he simply speaks upper case.)

We can’t measure justice and mercy. These are collective fictions — things we agree to believe to enable us to get along — and finding consensus on the immeasurable extends to political systems, religion, and most of economics. In a recent article [zwischenzugs] makes the point that methodologies in software development fall into the same category. Like collective societal fictions, methodologies tend to elicit strong emotional responses among those dealing with them.

A software development methodology is a playbook for getting from nothing to something. It’s a control system for how people working on the project spend their time. And there are a lot of these prescribed methods, from Agile to Waterfall, and any combination of letters is likely to turn an abbreviation for a methodology. An interesting game when hanging out in groups of software engineers is to start the “Have you ever tried the…” conversation. Just don’t expect to move to another topic anytime soon.

One disheartening aspect of methodologies is their resistance to scientific scrutiny. Two samples of development teams will differ wildly in so many characteristics that a meaningful comparison of the way they organize their work is not possible. Which will leaves us with anecdotes and opinions when discussing these things.

Current opinions regarding the impact of methodologies on the success of a project range from ‘marginal’ to ‘essential’. The latter position is mainly propagated by consultants selling agile certifications, so you may want to take it with a grain of salt. Whether a team adheres strongly to the methodology or adopts it in name only, it’s obvious they serve a purpose — but that purpose may not match the face value of the method.

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Shockingly, DARPA’s Brain Stimulator Might Not Be Complete Nonsense

November 13, 2017 by Sean Boyce 53 Comments

Where does your mind jump when you hear the mention of electroshock therapy? The use of electrical current to treat various medical conditions has a long and controversial history. Our fascination with the medical applications of electricity have produced everything from the most alarming of patent medicines to life-saving devices like pacemakers and the Automatic External Defibrillator.

The oldest reference I could find is the use of the torpedo fish to allegedly cure headaches, gout, and so on in 43 CE. Incidentally, Torpedo torpedo is an awesome species name.

Dosage: Apply live fish as needed to face? Source

Much more recently, there has been interest in transcranial direct current stimulation (tDCS). In essence, it’s a technique by which you pass an electrical current (typically about 2 milliamps) between strategically positioned electrodes on your head. The precise reason to do this is a bit unclear; different journal articles have suggested improvements in cognition, learning, and/or the potential treatment of various diseases.

I think most of us here spend a lot of time studying. The idea that a simple, noninvasive device can accelerate that is very attractive. We’ve covered a few people building their own such devices.

Unfortunately, what we want to be true is irrelevant. Superficially, this looks like a DARPA-funded panacea with no clearly established mechanism of action. Various commercial products are being sold that imply (but as usual, don’t directly state) that tDCS is useful for treating pretty much everything, with ample use of ‘testimonials’.

While tDCS can be prescribed by a physician in some countries to complement a stroke rehabilitation regime, for off-label purposes you may as well just go apply a fish to your face. Let’s dig into the literature and products that are out there and see if we can find the promise hiding amidst the hype.

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How Pure Is This Cup Of Joe? Coffee, Conspiracy, And Citizen Science

November 6, 2017 by Sean Boyce 38 Comments

Have you ever thought about coffee purity? It’s more something you’d encounter with prescription or elicit drugs, but coffee is actually a rather valuable commodity. If a seller can make the actual grounds go a bit further by stretching the brew with alternative ingredients there becomes an incentive to cheat.

If this sounds like the stuff rumors are made of, that’s because it is! Here in Ho Chi Minh City there are age-old rumors a coffee syndicate that masterfully passes off adulterated product as pure, high-grade coffee. Rumors are one thing, but the local media started picking up on these suspicions and that caught my attention. I decided to look to simple chemistry to see if I could prove or disprove the story.

What we want to investigate is whether price and coffee purity are related. If they are, then after accounting for the effect of price, we will want to know whether proximity to the market where artificial coffee flavoring is sold has an effect on coffee purity.

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Yellowing: The Plastic Equivalent Of A Sunburn

November 3, 2017 by Bob Baddeley 62 Comments

Your fancy white electronic brick of consumer electronics started off white, but after some time it yellowed and became brittle. This shouldn’t have happened; plastic is supposed to last forever. It turns out that plastic enclosures are vulnerable to the same things as skin, and the effects are similar. When they are stared at by the sun, the damage is done even though it might not be visible to you for quite some time.

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