What Voltage for the All-DC House?

The war of the currents was fairly decisively won by AC. After all, whether you’ve got 110 V or 230 V coming out of your wall sockets, 50 Hz or 60 Hz, the whole world agrees that the frequency of oscillation should be strictly greater than zero. Technically, AC won out because of three intertwined facts. It was more economical to have a few big power plants rather than hundreds of thousands of tiny ones. This meant that power had to be transmitted over relatively long distances, which calls for higher voltages. And at the time, the AC transformer was the only way viable to step up and down voltages.

No, not that AC/DC

But that was then. We’re right now on the cusp of a power-generation revolution, at least if you believe the solar energy aficionados. And this means two things: local power that’s originally generated as DC. And that completely undoes two of the three factors in AC’s favor. (And efficient DC-DC converters kill the transformer.) No, we don’t think that there’s going to be a switch overnight, but we wouldn’t be surprised if it became more and more common to have two home electrical systems — one remote high-voltage AC provided by the utilities, and one locally generated low-voltage DC.

Why? Because most devices these days use low-voltage DC, with the notable exception of some big appliances. Batteries store DC. If more and more homes have some local DC generation capability, it stops making sense to convert the local DC to AC just to plug in a wall wart and convert it back to DC again. Hackaday’s [Jenny List] sidestepped a lot of this setup and went straight for the punchline in her article “Where’s my low-voltage DC wall socket?” and proposed a few solutions for the physical interconnects. But we’d like to back it up for a minute. When the low-voltage DC revolution comes, what voltage is it going to be?

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Retrotechtacular: The Mother Of All (British) Demos

One of the most famous lectures in the history of technology was delivered by [Douglas Engelbart] in December 1968, at a San Francisco conference. In it he described for the first time most of what we take for granted in our desktop computers and networking today, several years before even the first microprocessor made it to market. It is revered not only because it was the first airing of these ideas, but because it was the event that inspired and influenced many of those who developed them and brought them to market. You may have heard of it by its poplar name: the Mother of All Demos.

This was an exciting time to be a technologist, as it must have been obvious that we lay on the brink of an age of ubiquitous computing. [Engelbart] was by no means alone in looking to the future and trying to imagine the impact that the new developments would have in the decades to come. On the other side of the Atlantic, at the British Post Office Telephone research centre at Dollis Hill, London, his British counterparts were no less active with their crystal ball gazing. In 1969 they produced our film for today, entitled complete with misplaced apostrophe “Telecommunications Services For The 1990’s” , and for our 2017 viewpoint it provides a quaint but fascinating glimpse of what almost might have been.

You can have any phone you want, as long as it's state-owned! A GPO 746 telephone from the early 1970s.
You can have any phone you want, as long as it’s state-owned! A GPO 746 telephone from the early 1970s.

Until the 1980s, the vast majority of British telephone services were a tightly regulated state monopoly run as part of the Post Office. There were only a few models of telephone available in the GPO catalogue, all of which were fixed installations with none of the phone sockets we take for granted today. Accessories such as autodiallers or answering machines were eye-wateringly expensive luxuries you’d only have found in offices, and since the fax machine was unheard of the height of data transfer technology was the telex. Thus in what later generations would call consumer information technology there really was only one player, so when they made pronouncements on the future they were a good indication of what you were likely to see in your home.

The film starts with a couple having a conversation, she in her bedroom and he in a phone box. Forgotten little touches such as a queue for a phone box or the then-cutting-edge-design Trimphone she’s using evoke the era, and the conversation leaves us hanging with the promise that their conversation would be better with video. After the intro sequence we dive straight into how the GPO thought their future network would look, a co-axial backbone with local circuits as a ring.

The real future-gazing starts with an office phone call to an Australian, at which we’re introduced to their concept of video calling with a colour CRT in a plastic unit that could almost be lifted from the set of The Jetsons. The presenter then goes on to describe a mass information service which we might recognise as something like our WWW, before showing us the terminal in more detail. Alongside the screen is a mock-up of a desktop console with keypad, cassette-based answerphone recorder, and a subscriber identity card slot for billing purposes. Period touches are a brief burst of the old harsh dial tone of a Strowger exchange, and mention of a New Penny, the newly-Decimalised currency. We’re then shown the system transmitting a fax image, of which a hard copy is taken by exposing a photographic plate to the screen.

Perhaps the most interesting sequence shows their idea of how an online information system would look. Bank statements and mortgage information are retrieved, though all with the use of a numeric keypad rather than [Englebart]’s mouse. Finally we see the system being used in a home office, a situation shown as farcical because the worker is continually harassed by his children.


This was the cutting edge in 1980, at least for people who hadn't seen France's Minitel. Fair use, via Wikimedia Commons.
This was the cutting edge in 1980, at least for people who hadn’t seen France’s Minitel. Fair use, via Wikimedia Commons.

So nearly five decades later, what did they get right and how much did they miss? The area you might expect them to be most accurate is oddly the one in which they failed most. The BT telecommunications backbone is now fibre-optic, and for the vast majority of us the last mile or two is still the copper pair it would have been a hundred years ago. In terms of the services though we have all of the ones they show us even if not in the form they envisaged. Fax and answering machines were everyday items by the 1980s, and though it didn’t gain much traction at the time we had video calling as a feature of most offices by the 1990s. We might however have expected them to anticipate a fax machine with a printer, after all it was hardly new technology.  Meanwhile the online service they show us is visibly an ancestor of Prestel, which they launched for the late 1970s and which failed to gain significant traction due to its expense.

Another area they miss is wireless. We briefly see a pager, but even though they had a VHF radio telephone service and the ancestors of our modern cellular services were on the drawing board on the other side of the Atlantic at the time, they completely miss a future involving mobile phones.

The full film is below the break. It’s a charming period production, and the wooden quality of the action shows us that while the GPO engineers might have been telephone experts, they certainly weren’t actors.

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Retrotechtacular: Robots, Robots Everywhere, with Kitschy Pronunciation

One of the great things about the human intellect is that we have the ability to build machines of varying complexity to do our bidding. As a major proponent of technology, the Chevrolet automobile corporation once dreamed of a future where the American housewife’s most mundane tasks are handled with the push of a button—one that sets a robot butler into action.

Chevy shows us what this future might look like in this short film, which they presented at the 1940 World’s Fair. A housewife’s faithful ‘robot’, pronounced throughout the picture as ‘robe-it’, has gone on the fritz. Naturally, she calls for a repairman. We see from the console controller that Roll-Oh the Robe-it can take care of all kinds of housewifely duties: he can answer the door and the phone, wash dishes, clean house, make beds, fetch hats, get dinner, and fix the furnace (and only the furnace). And that SCRAM! function? That’s never explained. We like to think it has to do with getting kids off the lawn, or could be used in conjunction with ‘get door’ to chase away would-be burglars. We get a glimpse of this when Roll-Oh answers the door and scares the daylights out of a young [Gary Sinise*] delivering flowers in a cop uniform.

Roll-Oh’s upper limbs have several Swiss Army knife-like implements in them. He uses a sharp one to cut the ribbon off of the flower box. Upon seeing the flowers, he gives them a gentle misting with his sprayer attachment. Dropped petals are no problem for Roll-Oh. He promptly vacuums them up from the thin industrial sound stage carpet with his big metal feet. Roll-Oh is then tasked with getting dinner. This amounts to him painstakingly opening a couple of cans and lighting candles with the torch hidden in his face.

While Roll-Oh the large ductwork butler is only a dream, Chevy wants you to know that smaller robe-its are all around us already. They’re regulating the heat in our stoves, browning our bread without burning it, and brewing our coffee in cool double-globe glass percolators. These tiny servants are capable of performing other tasks, like shutting off machinery when humans are too close, or sensing heat and engaging fire suppression systems. There is brief mention of something called the Petomat, an automatic dog feeding system which is essentially a bowl of food hidden in a latched box. The latch opens rather violently when the alarm clock connected to it goes off.

Robe-its are also performing more serious tasks, like keeping airplanes level and headed in the right direction. Of course, they’re also abundant in Chevrolet automobiles. A small one in the carburetor administers the proper mix of “gasoline calories and fresh air vitamins” to the engine. It’s rare to get to this level of technical detail, you know. Others watch over the spark, the intake manifold, and the voltage regulation. Up in the cab, friendly robe-its will happily traverse the AM dial at the push of a pre-set.

*Probably not actually [Gary Sinise].

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Found: Artifacts From the Future

MetaFilter is reporting that Wired magazine (available on paper) has killed one of our favorite features. Found: Artifacts From the Future was a back page that asked artists and designers to create possible future products. While the magazine generally had a positive view, even in its sloppy use of infoporn, Found always seemed to have a comforting cynicism. Products appeared helpful on the surface, but still exhibited modern pitfalls: Even if you took the big leap to get a Bluetooth implant, it still required a two year contract. The Responsibeer could tell exactly how drunk you were, but did nothing to prevent localized debauchery. A Smart Windshield provided info on unsafe drivers… while obscuring your view.

The short of it is: Found was our kind of futurism. It was excited about new technology while emphasizing all the frustrations we currently have trying to get consumer products to do what we want. It’s sad to see something that got people thinking beyond the now go away. MeFi has conveniently assembled links to all the online Found features.

[via Waxy]