We have all watched videos of concerts and events dating back to the 1950s, but probably never really wondered how this was done. After all, recording moving images on film had been done since the late 19th century. Surely this is how it continued to be done until the invention of CCD image sensors in the 1980s? Nope.
Although film was still commonly used into the 1980s, with movies and even entire television series such as Star Trek: The Next Generation being recorded on film, the main weakness of film is the need to move the physical film around. Imagine the live video feed from the Moon in 1969 if only film-based video recorders had been a thing.
We use a microcontroller without a second thought, in applications where once we might have resorted to a brace of 74 logic chips. But how many of us have spared a thought for how the microcontroller evolved? It’s time to go back a few decades to look at the first commercially available microcontroller, the Texas Instruments TMS1000.
Imagine A World Without Microcontrollers
The Texas Instruments Speak & Spell from 1978 was a typical use for the TMS1000. FozzTexx (CC-SA 4.0)
It’s fair to say that without microcontrollers, many of the projects we feature on Hackaday would never be made. Those of us who remember the days before widely available and easy-to-program microcontrollers will tell you that computer control of a small hardware project was certainly possible, but instead of dropping in a single chip it would have involved constructing an entire computer system. I remember Z80 systems on stripboard, with the Z80 itself alongside an EPROM, RAM chips, 74-series decoder logic, and peripheral chips such as the 6402 UART or the 8255 I/O port. Flashing an LED or keeping an eye on a microswitch or two became a major undertaking in both construction and cost, so we’d only go to those lengths if the application really demanded it. This changed for me in the early 1990s when the first affordable microcontrollers with on-board EEPROM came to market, but by then these chips had already been with us for a couple of decades.
It seems strange to modern ears, but for an engineer around 1970 a desktop calculator was a more exciting prospect than a desktop computer. Yet many of the first microcomputers were designed with calculators in mind, as was for example the Intel 4004. Calculator manufacturers each drove advances in processor silicon, and at Texas Instruments this led to the first all-in-one single-chip microcontrollers being developed in 1971 as pre-programmed CPUs designed to provide a calculator on a chip. It would take a few more years until 1974 before they produced the TMS1000, a single-chip microcontroller intended for general purpose use, and the first such part to go on sale. Continue reading “The TMS1000: The First Commercially Available Microcontroller”→
If you went to elementary school in the United States, you no doubt learned about Eli Whitney’s cotton gin as an example of how the industrial revolution took previously manual processes and replaced the low-efficiency of human labor with machines. The development of the cotton gin — patented in 1794 — involves an interesting lesson about solving engineering problems.
Farmers in the southern United States had a big problem. Tobacco was a cash crop, but it eventually left your fields barren and how to solve that problem wasn’t understood yet. Indigo was valuable for dye, but the British were eating away that market with indigo created in its colonies. Rice requires a lot of water and swamp, so it was only suitable for certain areas.
There was one thing that grew very readily in much of the land: cotton. Unfortunately, the cotton had little seeds you had to remove. A single person could clean — maybe — a pound of cotton a day. In the late 1700s, plantation owner Catharine Littlefield Greene introduced Whitney to a group of farmers were trying to decide if there was a way to make cotton a more profitable crop.
During the Second World War, the United States was pumping out weapons, aircraft, and tanks at an absolutely astonishing rate. The production of military vehicles and equipment was industrialized like never before, and with luck, never will be again. But even still, soldiers overseas would occasionally find themselves in unique situations that required hardware that the factories back at home couldn’t provide them with.
A Stinger machine gun in WWII
Which is precisely how a few United States Marines designed and built the “Stinger” light machine gun (LMG) during the lead-up to the invasion of Iwo Jima in 1945. The Stinger was a Browning .30 caliber AN/M2, salvaged from a crashed or otherwise inoperable aircraft, that was modified for use by infantry. It was somewhat ungainly, and as it was designed to be cooled by the air flowing past it while in flight, had a tendency to overheat quickly. But even with those shortcomings it was an absolutely devastating weapon; with a rate of fire at least twice that of the standard Browning machine guns the Marines had access to at the time.
Six Stingers were produced, and at least on a Battalion level, were officially approved for use in combat. After seeing how successful the weapon was during the invasion of Iwo Jima, there was even some talk of putting the Stinger into larger scale production and distributing them. But the war ended before such a plan could be put into place.
As such, the Stinger is an exceedingly rare example of a field modified weapon that was not only produced in significant numbers, but officially recognized and even considered for adoption by the military. But the story of this hacked machine gun actually started years earlier and thousands of kilometers away, as Allied forces battled for control of the Solomon Islands.
If you ask those of us who grew up somewhere in the 1950s to 1970s what our car would be like in the year 2020, we might have described an Avrocar. This top secret vehicle from Canadian Avro was part hovercraft and part jet-powered vertical takeoff vehicle. There were two prototypes actually made and [Real Engineering] has a short video on how the prototypes worked, how the real design might have worked, and even has a lot of footage of the actual devices. You can see the video below.
The designer, [Jack Frost], experimented with ground effect and the Coanda effect. The Canadian branch of Avro, a British company, worked with the U.S. military and if you look at it, you wonder how many UFO sightings it caused. Nothing like a flying disk 18 feet in diameter going over your backyard to make you call the newspapers. On second thought, it probably never got enough altitude for that to happen.
If you ask most people who invented the mouse, they won’t know. Those that do know, will say that Doug Englebart did. In 1964 he had a box with two wheels that worked like a modern mouse as part of his work at Stanford Research Institute. There is a famous demo video from 1968 of him showing off what looks a lot like an old Mcintosh computer. Turns out, two other people may have an earlier claim to a mouse — or, at least, a trackball. So why did you never hear about those?
The UK Mouse
Ralph Benjamin worked for Britain’s Royal Navy, developing radar tracking systems for warships. Right after World War II, Ralph was working on the Comprehensive Display System — a way for ships to monitor attacking aircraft on a grid. They used a “ball tracker.” Unlike Engelbart’s mouse, it used a metallic ball riding on rubber-coated wheels. This is more like a modern non-optical mouse, although the ball tracker had you slide your hand across the ball instead of the other way around. Sort of a trackball arrangement.
From the 1920s until the 1970s, most gasoline cars in the USA were using fuel that had lead mixed into it. The reason for this was to reduce the engine knocking effect from abnormal combustion in internal combustion engines of the time. While lead — in the form of tetraethyllead — was effective at this, even the 1920s saw both the existence of alternative antiknock agents and an uncomfortable awareness of the health implications of lead exposure.
We’ll look at what drove the adoption of tetraethyllead, and why it was phased out once the environmental and health-related issues came into focus. But what about its antiknock effects? We’ll also be looking at the alternative antiknock agents that took its place and how this engine knocking issue is handled these days.
