Rotary Phones And The Birth Of A Network

I can’t help but wonder how long it will be before the movie title  “Dial M for Murder” becomes mysterious to most of the population. After all, who has seen a dial phone lately? Sure, there are a few retro phones, but they aren’t in widespread use. It may not be murder, but it turns out that the dial telephone has its roots in death — or at least the business of death. But to understand why that’s true, you need to go back to the early days of the telephone.

Did you ever make a tin can phone with a string when you were a kid? That dates back to at least 1667. Prior to the invention of what we think of as the telephone, these acoustic phones were actually used for specialized purposes.

We all know that [Alexander Graham Bell] made a working telephone over a wire, drawing inspiration from the telegraph system. However, there’s a lot of dispute and many others about the same time were working on similar devices. It is probably more accurate to say that [Bell] was the first to successfully patent the telephone (in 1876, to be exact).

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Home Automation: Evolution Of A Term

Home automation: for me the term recalls rich dudes in the ’80s who could turn off their garage lights with remote-control pads. The stereotype for that era was the more buttons your system had—even non-enabled ones—the more awesome it was, and by extension any luxury remote control had to be three times the size of any TV remote.

And it was a luxury–the hardware was expensive and most people couldn’t justify it. Kind of like the laser-disc player of home improvements. The technology was opaque to casual tinkering, it cost a lot to buy, and also was expensive to install.

The richie-rich stereotypes were reinforced with the technology seen in Bond movies and similar near-future flicks. Everything, even silly things, is motorized, with chrome and concrete everywhere. You, the hero, control everything in the house in the comfort of your acrylic half-dome chair. Kick the motorized blinds, dim the track lighting, and volume up the hi-fi!

This Moonraker-esque notion of home automation turned out to be something of a red herring, because home automation stopped being pretty forever ago; eventually it became available to everyone with a WiFi router in the form of Amazon Echo and Google Nest.

But the precise definition of the term home automation remains elusive. I mean, the essence of it. Let’s break it down.

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Smart Gun Beaten By Dumb Magnets

[Plore], a hacker with an interest in safe cracking, read a vehemently anti-smart-gun thread in 2015. With the words “Could you imagine what the guys at DEF CON could do with this?” [Plore] knew what he had to do: hack some smart guns. Watch the video below the break.

Armed with the Armatix IP1, [Plore] started with one of the oldest tricks in the book: an RF relay attack. The Armatix IP1 is designed to fire only when a corresponding watch is nearby, indicating that a trusted individual is the one holding the gun. However, by using a custom-built $20 amplifier to extend the range of the watch, [Plore] is able to fire the gun more than ten feet away, which is more than enough distance to be dangerous and certainly more than the few inches the manufacturers intended.

Not stopping there, [Plore] went to the other extreme, creating what he calls an “electromagnetic compatibility tester” (in other words, a jammer) that jams the signal from the watch, effectively preventing a legitimate gun owner from firing their gun at 10 to 20 feet!

Not one to call it quits, [Plore] realised that the gun prevented illicit firing with a simple metal pin which it moved out of the way once it sensed the watch nearby. However, this metal just happened to be ferrous, and you know what that means: [Plore], with the help of some strong magnets, was able to move the pin without any electrical trickery.

Now, we’ve already covered the many hurdles that smart guns face, and this specific investigation of the state of smart gun technology doesn’t make the picture look any brighter. We’re aware that hindsight is always 20/20, so let us know in the comments how you would fix the problems with the Armatix IP1.
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Earth Ground And The Grid

The electrical grid transmits power over wires to our houses, and our Bryan Cockfield has covered it very well in his Electrical Grid Demystified series, but what part does the earth ground play? It’s commonly known to be used for safety, but did you know that in some cases it’s also used for power transmission?

Typical House Grounding System

Grounding system normal case
Grounding system normal case

A pretty typical diagram for the grounding system for a house is shown here, along with a few of the current carrying conductors commonly called live and neutral. On the far left is the transformer outside the house and on the far right is an appliance that’s plugged in. In between them is a breaker panel and a wall socket of the style found in North America. The green dashed line shows the normal path for current to flow.

Notice the grounding electrodes for making an electrical connection with the earth ground. To use the US National Electrical Code (NEC) as an example, article 250.52 lists eight types of grounding electrodes. One very good type is an electrode encased in concrete since concrete continues to draw moisture from the ground and makes good physical contact due to its weight. Another is a grounding rod or pipe at least eight feet long and inserted deep enough into the ground. By deep enough, we mean to include factors such as the fact that the frost line doesn’t count as a good ground since it has a high resistance. You have to be careful of using metal water pipes that seemingly go into the ground, as sections of these are often replaced with non-metallic pipes during regular maintenance.

Notice also in the diagram that there are places where the various metal cases are connected to the grounding system. This is called bonding.

Now, how does all this system grounding help us? Let’s start with handling a fault.

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The End Of Arduino 101: Intel Leaves Maker Market

This looks like the end of the road for Intel’s brief foray into the “maker market”. Reader [Chris] sent us in a tip that eventually leads to the discontinuation notice (PCN115582-00, PDF) for the Arduino 101 board. According to Intel forum post, Intel is looking for an alternative manufacturer. We’re not holding our breath.

We previously reported that Intel was discontinuing its Joule, Galileo, and Edison lines, leaving only the Arduino 101 with its Curie chip still standing. At the time, we speculated that the first wave of discontinuations were due to the chips being too fast, too power-hungry, and too expensive for hobbyists. Now that Intel is pulling the plug on the more manageable Arduino 101, the fat lady has sung: they’re giving up on hardware hackers entirely after just a two-year effort.

According to the notice, you’ve got until September 17 to stock up on Arduino 101s. Intel is freezing its Curie community, but will keep it online until 2020, and they’re not cancelling their GitHub account. Arduino software support, being free and open, will continue as long as someone’s willing to port to the platform.

Who will mourn the Arduino 101? Documentation was sub-par, but a tiny bit better than their other hacker efforts, and it wasn’t overpriced. We’re a little misty-eyed, but we’re not crying.  You?

[via Golem.de]

Review: TS100 Soldering Iron

Temperature-controlled soldering irons can be cheap, lightweight, and good. Pick any two of those attributes when you choose an iron, because you’ll never have all three. You might believe that this adage represents a cast-iron rule, no iron could possibly combine all three to make a lightweight high-performance tool that won’t break the bank! And until fairly recently you’d have had a point, but perhaps there is now a contender that could achieve that impossible feat.

The Miniware TS100 is a relatively inexpensive temperature-controlled soldering iron from China that has made a stealthy entry to the market, and which some online commentators claim to be the equal of far more expensive professional-grade irons. We parted with just below £50 (around $60) to place an order for a TS100, and waited for it to arrive so we could see what all the fuss was about. Continue reading “Review: TS100 Soldering Iron”

Huge Functionality, Small Package: A Custom Tablet, Raspberry Style

As the adage goes, “if you want something done right, do it yourself.” Desirous of a tablet but preferring to eschew consumer models, [Stefan Vorkoetter] constructed his own compact and lightweight Raspberry Pi tablet, covering several extra miles in the process.

The tablet makes use of a Raspberry Pi 3 and the official touchscreen, with the final product marginally larger than the screen itself. Designed with a ‘slimmer the better’ profile in mind, [Vorkoetter] had to modify several components to fit this precept; most obvious of these are the removal of the Pi’s GPIO headers, USB, and Ethernet ports, and removing the USB power out port from the touchscreen controller board so the two could be mounted side-by-side.

An Adafruit PowerBoost 1000C handles charging the 6200 mAh battery — meaning up to six hours(!) of YouTube videos — via a micro USB, but only after [Vorkoetter] attached a pair of home-made heatsinks due to negligible air flow within the case. A modified USB audio adapter boosts the Pi’s audio capabilities, enabling the use of headphones, a mic, and a built-in speaker which is attached to the tablet’s back cover.

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