They adorn the ends of Cat5 network patch cables and the flat satin cables that come with all-in-one printers that we generally either toss in the scrap bin or throw away altogether. The blocky rectangular plugs, molded of clear plastic and holding gold-plated contacts, are known broadly as modular connectors. They and their socket counterparts have become ubiquitous components of the connected world over the last half-century or so, and unsurprisingly they had their start where so many other innovations began: from the need to manage the growth of the telephone network and reduce costs. Here’s how the modular connector got that way.
What’s worse than powering up your latest build for the first time only to have absolutely nothing happen? OK, maybe it’s not as bad as releasing the Magic Smoke, but it’s still pretty bewildering to have none of your blinky lights blink like they’re supposed to.
What you do at that point is largely a matter of your troubleshooting style, and when [Scott M. Baker]’s Raspberry Pi jukebox build failed to chooch, he returned to first principles and checked the power cable. That turned out to be the culprit, but instead of giving up there, he did a thorough series of load tests on multiple USB cables to see which ones were suspect, with interesting results.
[Scott] originally used a cable with a USB-A on one end and a 3.5-mm barrel plug on the other with a switch in between, under the assumption that the plug on the Pi end would be more robust, as well as to have a power switch for the jukebox. Testing that cable using an adjustable DC load would prove that the cable was unfit for Pi duty, dropping the voltage to under 2 volts at a measly 500-mA load. Other cables proved much better under load, even those with USB mini jacks and even one with a 5.5-mm barrel. But the larger barrel-plug cable also proved to be a stinker when it was paired with an inline switch. In the video below, [Scott] walks through not only the testing process, but also gives a quick tour of his homebrew DC load.
The lesson is clear: not all USB cables are created equal, so caveat hacker. And if you’ve got a yen to check the cables in your junk bin like [Scott] did, this full-featured smart DC load might be just the thing.
There’s been a lot of fuss over Apple’s move to ditch the traditional audio jack. As for me, I hope I never have to plug in another headphone cable. This may come off as gleeful dancing on the gravesite of my enemy before the hole has even been dug; it kind of is. The jack has always been a pain point in my devices. Maybe I’ve just been unlucky. Money was tight growing up. I would save up for a nice set of headphones or an mp3 player only to have the jack go out. It was a clear betrayal and ever since I’ve regarded them with suspicion. Is this the best we could do?
I can’t think of a single good reason not to immediately start dumping the headphone jack. Sure it’s one of the few global standards. Sure it’s simple, but I’m willing to take bets that very few people will miss the era of the 3.5mm audio jack once it’s over. It’s a global episode of the sunk cost fallacy.
In the usual way hindsight is 20/20, the 3.5mm audio jack can be looked at as a workaround, a stop over until we didn’t need it. It appears to be an historic kludge of hack upon hack until something better comes along. When was the last time it was common to hook an Ethernet cable into a laptop? Who would do this when we can get all the bandwidth we want reliably over a wireless connection. Plus, it’s not like most Ethernet cables even meet a spec well enough to meet the speeds they promise. How could anyone reasonably expect the infinitely more subjective and variable headphone and amplifier set to do better?
But rather than just idly trash it, I’d like to make a case against it and paint a possible painless and aurally better future.
As you may have heard, the iPhone 7 is ditching the 3.5 mm headphone jack in the name of progress and courage. Whatever your take on that, it leaves the end user out in the cold if — for instance — their preferred headphones still use the old format. Here to save you from an untimely upgrade is YouTuber [Kedar Nimbalkar], who has modified a Bluetooth Smartwatch to incorporate a 3.5 mm jack to allow continued use your current headphones.
After opening up the smartwatch [Nimbalkar] removes the speaker, solders in a 3.5 mm headphone jack and clips out an opening in the watch’s case that maintains the watch’s sleek exterior.
If you’ve watched the tech news these last few months, you probably have noticed the rumors that Apple is expected to dump the headphone jack on the upcoming iPhone 7. They’re not alone either. On the Android side, Motorola has announced the Moto Z will not have a jack. Chinese manufacturer LeEco has introduced several new phones sans phone jack. So what does this mean for all of us?
This isn’t the first time a cell phone company has tried to design out the headphone jack. Anyone remember HTC’s extUSB, which was used on the Android G1? Nokia tried it with their POP Port. Sony Ericsson’s attempt was the FastPort. Samsung tried a dizzying array of multi-pin connectors. HP/Palm used a magnetic adapter on their Veer. Apple themselves tried to reinvent the headphone jack by recessing it in the original iPhone, breaking compatibility with most of the offerings on the market. All of these manufacturers eventually went with the tried and true ⅛” headphone jack. Many of these connectors were switched over during an odd time in history where Bluetooth was overtaking wired “hands-free kits”, and phones were gaining the ability to play mp3 files.
Work on HaDge – the Hackaday con badge, continues in bits and spurts, and we’ve had some good progress in recent weeks. HaDge will be one conference badge to use at all conferences, capable of communicating between badges.
Picking up from where we left off last time, we had agreed to base it around the Atmel D21, a 32-bit ARM Cortex M0+ processor. To get some prototype boards built to help with software development, we decided to finish designing the HACK before tackling HaDge. HACK is a project that [Michele Perla] started that we have sort of assimilated to act as the prototyping platform for HaDge. We wanted a compact micro-controller board and hence opted for the SAM D21E – a 32 pin package with 26 IO’s.
[Michele Perla] had earlier designed HACK based on the larger 32 pin SAM D21G and used Eagle to draw the schematic and layout. Using the Eagle to KiCad script, he quickly converted the project and got on to making the board layout. I took up the rear guard, and worked on making his schematic (pdf) “pretty” and building up a schematic library of symbols. While [Michele] finished off the board layout, I worked on collecting STEP models for the various footprints we would be using, most of which I could get via 3dcontentcentral.com. The few I couldn’t were built from scratch using FreeCAD. The STEP models were converted to VRML using FreeCAD. Using [Maurice]’s KiCad Stepup script, we were able to obtain a complete STEP model of the HACK board.
HACK is now ready to go for board fabrication and assembly. We plan to get about 20 boards made and hand them out to developers for working on the software. The GitHub repository has all the current files for those who’d like to take a look – it includes the KiCad source files, PDFs, gerbers, data sheets and images. The board will be breadboard compatible and also have castellated pads to allow it to be soldered directly as a module. Let us know via group messaging on the HACK project page if you’d like to get involved with either the software or hardware development of HaDge.
In a forthcoming post, we’ll put out ideas on how we plan to take forward HaDge now that HACK is complete. Stay tuned.
A couple of days back, we wrote about the HACK – a prototyping platform designed by [Michele Perla] based on the Atmel SAM R21 MCU. It’s one of the new breed of devices consisting of an ARM Cortex-M0 MCU + IEEE 802.15.4 Wireless radio bundled together. This was exciting since we could pack a lot of punch in the HaDge hardware. We planned to use the same design later to power the HaDge. Building HACK would have allowed us to get it in the hands of the software team, while the hardware folks worked on the real HaDge layout.
The HACK design was ready for review and we asked around to verify the antenna layout, which was the part we were not too sure about. We asked Atmel for help with verifying the layout. That’s when we had the facepalm moment. They asked us – “What about FCC certification?” Since we plan to build the badges in quantities of a few hundred at the very least, it’s obvious we cannot escape from FCC certification. A design based around the R21 is ruled out – the cost of obtaining approval is pretty high. This means we need to punt the R21 and instead use an off-the-shelf radio module which is already FCC certified. Sigh.
Now the good news. This is a setback in terms of time, and effort put in by [Michele]. But beyond that, we’re good to go back to the drawing board and start afresh. First off, we decided to revert back to the Atmel D21 as the main controller. It’s a fairly decent MCU, and there’s a fairly robust tool chain available that a lot of people are familiar with. For the Radio, we are looking at some of these available options :
The last one from Microchip looks quite promising. But we’re open for better and cheaper suggestions, so please chime in with your comments.