Retrotechtacular: Car Navigation Like It’s 1971

Anyone old enough to have driven before the GPS era probably wonders, as we do, how anyone ever found anything. Navigation back then meant outdated paper maps, long detours because of missed turns, and the far too frequent stops at dingy gas stations for the humiliation of asking for directions. It took forever sometimes, and though we got where we were going, it always seemed like there had to be a better way.

Indeed there was, but instead of waiting for the future and a constellation of satellites to guide the way, some clever folks in the early 1970s had a go at dead reckoning systems for car navigation. The video below shows one, called Cassette Navigation, in action. It consisted of a controller mounted under the dash and a modified cassette player. Special tapes, with spoken turn-by-turn instructions recorded for a specific route, were used. Each step was separated from the next by a tone, the length of which encoded the distance the car would cover before the next step needed to be played. The controller was hooked to the speedometer cable, and when the distance traveled corresponded to the tone length, the next instruction was played. There’s a long list of problems with this method, not least of which is no choice in road tunes while using it, but given the limitations at the time, it was pretty ingenious.

Dead reckoning is better than nothing, but it’s a far cry from GPS navigation. If you’re still baffled by how that cloud of satellites points you to the nearest Waffle House at 3:00 AM, check out our GPS primer for the details.

Continue reading “Retrotechtacular: Car Navigation Like It’s 1971”

Hair-Raising Tales of Electrostatic Generators

We tend to think of electricity as part of the modern world. However, Thales of Mietus recorded information about static electricity around 585 BC.  This Greek philosopher found that rubbing amber with fur would cause the amber to attract lightweight objects like feathers. Interestingly enough, a few hundred years later, the aeolipile — a crude steam engine sometimes called Hero’s engine — appeared. If the ancients had put the two ideas together, they could have invented the topic of this post: electrostatic generators. As far as we know, they didn’t.

It would be 1663 before Otto von Guericke experimented with a sulfur globe rubbed by hand. This led to Isaac Newton suggesting glass globes and a host of other improvements from other contributors ranging from a woolen pad to a collector electrode. By 1746, William Watson had a machine consisting of multiple glass globes, a sword, and a gun barrel. Continue reading “Hair-Raising Tales of Electrostatic Generators”

Retrotechtacular: AM Radios, Core Memory, And Color TV, What Was Hot In Chips In ’73

As part of writing tech stories such as those we feature here at Hackaday, there is a huge amount of research to be done.  We trawl through pages and pages of obscure blogs, videos, and data sheets. Sometimes we turn up resources interesting enough that we file them away, convinced that they contain the nucleus of another story at some point in the future.

Today’s topic of entertainment is just such a resource, courtesy of the Internet Archive. It’s not a video as we’d often provide you in a Retrotechtacular piece, instead it’s the February 1973 edition of the Fairchild Semiconductor Linear Integrated Circuits Catalog. Books like this one that could be had from company sales representatives were highly prized in the days before universal Internet access to data sheets, and the ink-on-paper datasheets within it provide a fascinating snapshot of the integrated electronics industry as it was 45 years ago.

The first obvious difference between then and now is one of scale, this is a single volume containing Fairchild’s entire range. At 548 pages it wouldn’t have been a slim volume by any means, but given that Fairchild were at the time one of the big players in the field it is unimaginable that the entire range of a 2018 equivalent manufacturer could be contained in the same way. Given that the integrated circuit was at the time an invention barely 15 years old, we are looking at an industry still in relative infancy.

The catalog has a series of sections with familiar headings: Operational amplifiers, comparators, voltage regulators, computer/interface, consumer, and transistor/diode arrays with analog switches. Any modern catalog will have similar headings, and there are even a few devices you will find have survived the decades. The μA741 op-amp (page 64) from its original manufacturer has not yet become a commodity product here, and it sits alongside familiar devices such as the μA7800 series (page 201) or μA723 (page 194) regulators.

Continue reading “Retrotechtacular: AM Radios, Core Memory, And Color TV, What Was Hot In Chips In ’73”

Computers That Never Were

Today it is easier than ever to learn how to program a computer. Everyone has one (and probably has several) and there are tons of resources available. You can even program entirely in your web browser and avoid having to install programming languages and other arcane software. But it wasn’t always like this. In the sixties and seventies, you usually learned to program on computers that didn’t exist. I was recently musing about those computers that were never real and wondering if we are better off now with a computer at every neophyte’s fingertips or if somehow these fictional computing devices were useful in the education process.

Back in the day, almost no one had a computer. Even if you were in the computer business, the chances that you had a computer that was all yours was almost unheard of. In the old days, computers cost money — a lot of money. They required special power and cooling. They needed a platoon of people to operate them. They took up a lot of space. The idea of letting students just run programs to learn was ludicrous.

Continue reading “Computers That Never Were”

Retrotechtacular: Radio to Listen to When you Duck and Cover

CONELRAD may sound like the name of a fictional android, but it is actually an acronym for control of electronic radiation. This was a system put in place by the United States at the height of the cold war (from 1951 to 1963) with two purposes: One was to disseminate civil defense information to the population and, also, to eliminate radio signals as homing beacons for enemy pilots.

Continue reading “Retrotechtacular: Radio to Listen to When you Duck and Cover”

Retrotechtacular: An Oceanographic Data Station Buoy For The 1960s

When we watch a TV weather report such as the ones that plaster our screens during hurricane season, it is easy to forget the scale of the achievement they represent in terms of data collection and interpretation. Huge amounts of data from a diverse array of sources feed weather models running on some of our most powerful computers, and though they don’t always forecast with complete accuracy we have become used to their getting it right often enough to be trustworthy.

It is also easy to forget that such advanced technology and the vast array of data behind it are relatively recent developments. In the middle of the twentieth century the bulk of meteorological data came from hand-recorded human observations, and meteorologists were dispatched to far-flung corners of the globe to record them. There were still significant areas of meteorological science that were closed books, and through the 1957 International Geophysical Year there was a concerted worldwide effort to close that gap.

We take for granted that many environmental readings are now taken automatically, and indeed most of us could produce an automated suite of meteorological instruments relatively easily using a microcontroller and a few sensors. In the International Geophysical Year era though this technology was still very much in its infancy, and the film below the break details the development through the early 1960s of one of the first automated remote ocean sensor buoys.

Perhaps our last sentence conjures up a vision of something small enough to hold, from all those National Geographic images of intrepid oilskin-clad scientists launching them from the decks of research vessels. But the technology of the early 1960s required something a little more substantial, so the buoy in question is a (using the units of the day) 100 ton circular platform more in the scale of a medium-sized boat. Above deck it was dominated by an HF (shortwave) discone antenna and its atmospheric instrument package. Below deck (aside from its electronic payload) it had a propane-powered internal combustion engine and generator to periodically charge its batteries. In use it would be anchored to the sea floor, and it was designed to operate even in the roughest of maritime conditions.

The film introduces the project, then looks at the design of a hull suitable for the extreme conditions like a hurricane. We see the first prototype being installed off the Florida coast in late 1964, and follow its progress through Hurricane Betsy in 1965. The mobile monitoring station in a converted passenger bus is shown in the heart of the foul weather, receiving constant telemetry from the buoy through 40 foot waves and 110 mph gusts of wind.

We are then shown the 1967 second prototype intended to be moored in the Pacific, this time equipped with a computerised data logging system. A DEC PDP-8 receives the data mounted in the bus, and are told that this buoy can store 24 hours at a stretch for transmission in one go. Top marks to the film production team for use of the word “data” in the plural.

Finally we’re told how a future network of the buoys for presumably the late 1960s and early 1970s could be served by a chain of receiving stations for near-complete coverage of the major oceans. At the height of the Cold War this aspect of the project would have been extremely important, as up-to-the-minute meteorological readings would have had considerable military value.

The film makes an engaging look at a technology few of us will ever come directly into contact with but the benefits of which we will all feel every time we see a TV weather forecast.

Continue reading “Retrotechtacular: An Oceanographic Data Station Buoy For The 1960s”

Retrotechtacular: DC to DC Conversion, Rotary Style

If you want to convert one voltage to another, what do you do? Well, if you are talking DC voltages today, you’ll probably use a DC to DC converter. Really, these converters generate some sort of AC waveform and then use either an inductor or a transformer to boost or buck the voltage as desired. Then they’ll convert it back to DC. If you are talking AC voltages, you could just use a transformer. But think about this: a transformer has two sides. The primary makes an alternating magnetic field. Just like rotating a shaft with magnets on it could. The secondary converts that alternating magnetic field into electricity just like a generator does. In other words, a transformer is just a generator that takes an AC input instead of a rotating mechanical input.

That’s a bit of an oversimplification, but in the old days, a lot of mobile radios (and other devices) took this idea to its logical conclusion. A M-G (Motor Generator) set was little more than a motor connected to a generator. The motor might take, say, 12V DC and the output could be, for example 300V AC that would get rectified for the plate voltage in a tube radio.

Continue reading “Retrotechtacular: DC to DC Conversion, Rotary Style”