These modules, sold in pairs, communicate serially without extra wires or cables. With a DB-9 serial port on one side and a 110/220V power cable slot on the other, they transmit and receive high-frequency signals over power lines using high-pass filters, all with low h.f. output to keep from interfering with electric power on the network. They can transmit data to 500 m at up to 230 kbps, with 56-bit DES data encryption for RS232 signals. The modules are based on a 32-bit RISC processor with 8 MB SDRAM and 4 MB flash memory. They work on 110V or 220V supplies, have built-in surge protectors, and are DTE/DCE selectable.
Samsung's Galaxy line of smartphones used to fare quite well in the repairability department, but last year's flagship S5 model took a tumble, scoring a meh-inducing 5/10. Will the newly redesigned S6 lead us back into star-studded territory, or will we sink further into the depths of a repairability black hole?
In 2003, the world contained just over 500 million Internet-connected devices. By 2010, this figure had risen to 12.5 billion connected objects, almost six devices per individual with access to the Internet. Now, as we move into 2015, the number of connected 'things' is expected to reach 25 billion, ultimately edging toward 50 billion by the end of the decade.
NASA engineer Brian Trease studied abroad in Japan as a high school student and used to fold fast-food wrappers into cranes using origami techniques he learned in library books. Inspired by this, he began to imagine that origami could be applied to building spacecraft components, particularly solar panels that could one day send solar power from space to be used on earth.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.