Stratum 1 Grandmaster Time Server On A Budget

July 15, 2022 by Chris Lott 20 Comments

[Jeff Geerling] has been following the various open source time projects for some time now, and is finally able to demonstrate a working and affordable solution for nanoseconds-accurate timekeeping in your local lab. The possibility of a low-cost time server came about with the introduction of the Raspberry Pi CM4 compute module back in Oct 2020, whose Broadcom network chip (BCM54210PE) supports PTP (Precision Time Protocol, IEEE-1588) 1PPS output and hardware-based time stamping. Despite the CM4 data sheet specifying PTP support, it wasn’t available in the kernel. An issue was raised in Feb last year, and Raspberry Pi kernel support was finally released this month.

[Jeff] demonstrates how easy it is to get two CM4 modules to synchronize to within a few tens of nanoseconds in the video below the break. That alone can be very useful on many projects. But if you want really stable and absolute time, you need a stratum 1 external source. These time servers, called grandmasters in PTP nomenclature, have traditionally been specialized pieces of kit costing tens of thousands of dollars, using precision oscillators for stability and RF signals from stratum 0 devices like navigation satellites or terrestrial broadcast stations to get absolute time. But as Lasse Johnsen, who worked on the kernel updates remarks in the video:

In 2022 these purpose-built grandmaster clocks from the traditional vendors are about as relevant as the appliance web servers like the Raq and Qube were back in 1998.

It is now possible to build your own low-cost stratum 1 time server in your lab from open source projects. Two examples shown in the video. The Open Time Server project’s Timecard uses a GNSS satellite receiver and a Microchip MAC-SA5X Rubidium oscillator. If that’s overkill for your projects or budget, the Time4Pi CM4 hat is about to be release for under $200. If accurate time keeping is your thing, the technology is now within reach of the average home lab. You can also add PTP to a non-CM4 Raspberry Pi — check out the Real-Time HAT that we covered last year.

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Automate Internet Life With Python

July 12, 2022 by Al Williams 19 Comments

Most of us are adept enough with computers that you know what they can easily do and what they can’t. Invent a new flavor of ice cream? Not easy. Grab the news headlines related to Arduinos from your favorite news feed? Relatively easy. But, of course, the devil is in the details. FreeCodeCamp has a 3-hour course from [Frank Andrade] that dives into the gory details of automating web tasks using Python and a variety of libraries like Path, Xpath, and Selenium. You can watch the course, below.

Topics start off with grabbing tables from websites and PDFs. But it quickly graduates to general-purpose web scraping and even web automation. These techniques can be very useful for testing browser-based applications, too.

By the end, you’ve created an executable that grabs news every day and automatically generates an Excel report. There’s also a little wind down about WhatApp automation. A little something for everyone. We also greatly approved of [Frank]’s workspace which appears in the background. Looks like he would enjoy reading Hackaday.

Honestly, while we’ve seen easier methods of automating the browser, there’s something appealing about having the control something like Python affords. Sure beats building hardware to simulate a human-in-the-loop.

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Remembering NICAM: Deep-Dive Into A Broadcasting Legacy

July 10, 2022 by Maya Posch 17 Comments

Although for many the introduction of color television would have seemed to be the pinnacle of analog broadcast television, the 1970s saw the development of stereo audio systems to go with TV broadcasts, including the all-digital NICAM. With NICAM broadcasts having ceased for about a decade now, the studio equipment for encoding and modulating NICAM can now be picked up for cheap. This led [Matthew Millman] to not only buy a stack of Philips NICAM studio gear, but also tear them down and set up a fully working NICAM encoding/decoding system with an Arcam Delta 150 as receiver and Philips PM5687 encoder.

Finally, the Philips PM5688 test receiver is analyzed. This is the component that studios would have used to ensure that the NICAM encoding and modulating systems were working properly. Although public NICAM broadcasts started in the late 1980s, the system was originally developed to enable point to point transfers of audio data within a transmission system. This was made very easy due to the digital nature of the system, and made enabling it for public broadcasts relatively straightforward once receivers became affordable enough.

Of note is that NICAM was only ever used in Europe and some Asian-Pacific countries, with others using the German Zweikanalton. This was a purely analog (two FM channels) system, and the US opted to use its MTS system, that was quite similar to the German system in terms of transmitting multiple FM channels alongside the TV signal. With digital TV gradually overtaking analog TV transmissions, the future of NICAM, MTS and others was sealed, leaving us with just these time capsules we can build up using old studio equipment.

Hacker Camps Post-Pandemic, Electromagnetic Field 2022

July 5, 2022 by Jenny List 21 Comments

After a four-year hiatus and a cancelled event, it was time earlier this month for British and European hackers to return to their field in Herefordshire. A special field, Eastnor Castle Deer Park, venue for the Electromagnetic Field 2022 hacker camp. I packed up an oversized rucksack and my folding bike, and set off to enjoy a few days in the company of my fellow geeks.

As the first of the large European hacker camps since 2019 there was both an excitement and a slight trepidation in finally hanging out with several thousand people, even if mostly outdoors. The UK has a good COVID vaccine uptake and the camp organisers requested that attendees test themselves before travelling to Eastnor, but after two years of precautions and the pandemic still being with us there’s still some risk to take into account. Happily they were able to strike a decent balance between precautions and event progress, and we were able to proceed with a fairly normal hacker camp.

Plenty Of Talks, But They’re Not Online Yet

Sadly the extensive programme of talks has yet to make it onto YouTube or media.ccc.de at the time of writing, so the section I’d normally devote to them may have to wait for another time. Thus this write-up is more about the social aspect than the action.

Eastnor Castle Deer Park lies in a secluded Herefordshire valley, and the entry is vla a small estate road that treats you to an unfolding vista as you approach, of the marquees and other structures nestled among the trees. The usual queue for a wristband and you’re in, with the minor inconvenience of a trek trough the site to wherever your village lies. This year I was with my hackerspace in the Milton Keynes Makerspace village, next to one of the estate roads at the side of the valley and clustered round a tent with the commendable purpose of distributing free cups of very high quality tea. My tent up, I was ready to tour the site, and renew some friendships after so long apart. Continue reading “Hacker Camps Post-Pandemic, Electromagnetic Field 2022” →

Atari At 50: The Story Of Our Lives

June 27, 2022 by Jenny List 14 Comments

It’s been a year of anniversaries, what with the 40th birthday of both the Commodore 64 and the Sinclair ZX Spectrum. But there’s another anniversary that in a sense tops them all, today marks 50 years since Nolan Bushnell and Ted Dabney incorporated Atari Inc, a name that will forever be synonymous with the development of the computer game industry. PC Magazine have marked the event with a retrospective, an affectionate look at the progress from Spacewar! coin-ops to the unsuccessful Jaguar console of the 1990s, and it pulls no punches over the lacklustre management that oversaw its decline in later years.

For us the high points of the Atari story were the VCS console and the ST line of computers, which probably best represent the brand’s successes in Europe where this is being written. It’s with something of a wince that we remember watching an Atari Lynx advert in a British cinema, in which the laugh came when the teenager-unaffordably high price was revealed. At least diehard Atari fans can take solace in that by then Commodore was equally being run into the ground.

One criticism PC Magazine makes is that the current Atari incarnation is doing little beyond rehashing past glories, and perhaps they’re right. Last year we covered their release of some new cartridges for the VCS.

3D Printer Helps Make A Neat Lyric Video

June 17, 2022 by Lewin Day 4 Comments

These days, it’s a lot easier to get attention online if your lovely music comes with some kind of visual accompaniment. Of course, shooting a full-scale music video can be expensive, so lyric videos have become a more affordable, approachable avenue that are growing in popularity. [prash] whipped one up recently with the help of a 3D printer.

The video is a timelapse of a 3D print, something we’re very familiar with around these parts. [prash] embedded words in the various layers of the objects to be printed. Thus, as the prints are laid down on the build plate, the words are revealed to the camera shooting the time lapse. The scene is further improved by shaping the prints to reference the lyrics of the song, and using attractive infill designs like spirals and stripes. There are even some strategically placed clouds and pretty lighting to improve the effect.

It’s a neat use of 3D printing, and an artful one at that. We’re pretty confident that [prash] has put together a highly unique lyric video, and it’s much more impressive than the dodgy 3D printing [Will.i.am] featured in his not-quite-a-Britney song a decade ago. Video after the break.

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Mining And Refining: Helium

June 15, 2022 by Dan Maloney 46 Comments

With a seemingly endless list of shortages of basic items trotted across newsfeeds on a daily basis, you’d be pardoned for not noticing any one shortage in particular. But in among the shortages of everything from eggs to fertilizers to sriracha sauce has been a growing realization that we may actually be running out of something so fundamental that it could have repercussions that will be felt across all aspects of our technological society: helium.

The degree to which helium is central to almost every aspect of daily life is hard to overstate. Helium’s unique properties, like the fact that it remains liquid at just a few degrees above absolute zero, contribute to its use in countless industrial processes. From leak detection and welding to silicon wafer production and cooling the superconducting magnets that make magnetic resonance imaging possible, helium has become entrenched in technology in a way that belies its relative scarcity.

But where does helium come from? As we’ll see, the second lightest element on the periodic table is not easy to come by, and considerable effort goes into extracting and purifying it enough for industrial use. While great strides are being made toward improved methods of extraction and the discovery of new deposits, for all practical purposes helium is a non-renewable resource for which there are no substitutes. So it pays to know a thing or two about how we get our hands on it.

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