Electromagnetic Field Drops 2022 Talk Videos

Earlier this year we made the journey to a field in the West of England for the Electromagnetic Field hacker camp. It was the usual few days of fun in the open air, but due to a few technical difficulties we were unable to point you to any of the talks. We’re happy to note that now the dust has settled they are uploading talks, and there are a decent number up on YouTube with more to come.

Paging through the talks uploaded so far, and there’s plenty to get your teeth into. We’ll start with a couple that should be viewed as a pair,  [Robin Wilson] on UK railway signalling, and [Anthony Williams] giving us a crash course in railway safety, and then while we’re on a railway theme continue to [Hugh Wells] on hacking the train ticket system. Those first two amply demonstrate the best in our community, in that here are professionals sharing knowledge with us we’d never hear without working in that field.

Another esoteric talk that’s typical of a hacker camp schedule and which should be of interest to anyone who has wrestled with time synchronization comes from [John Dalziel], who gives us a brief history of time zones and daylight saving time. A talk that had me riveted during a train journey though came from [Cybergibbons], who describes penetration testing at a cruise ship scale.

These are just a few of the ones uploaded thus far, and as this is being written there are more appearing. So keep checking and you’ll see some really good ones. Meanwhile, have a read of our report from the event.

The Hackaday Summer Camp Survival Guide

It’s a feature of summer for us, the round of hacker camps in which members of our community gather in fields and spend a few days relaxing and doing what we do best. This summer I’ll have been to four of them by September, one of which was unexpected because a last-minute ticket came my way. For Hackaday they’re a chance to connect with our readers and maybe see come of the coolest stuff in person.

If you consult the wiki for your hacker camp of choice then you’ll usually find a page of tips about what to bring. Starting with a tent and a sleeping bag and probably going on to sunscreen, a hat, and maybe how to avoid dehydration. I’d probably add spare toilet paper and disinfectant spray in case the toilets are nightmarish. All very practical stuff, but expressed in a dry list format that doesn’t really tell you what to expect. A hacker camp can be overwhelming if you’ve not been to one before, so how do you get the best out of it? Here are a few tips based on our experience. Continue reading “The Hackaday Summer Camp Survival Guide”

Badges Of 2022: EMF TiDAL

As we slowly return to a summer of getting together in fields for our festivals of hackery, it’s time to look at another of this year’s crop of badges. The UK’s Electromagnetic Field, or EMF, is normally a two-yearly event, but its return this year comes after a four year absence due to the pandemic. The EMF 2022 badge is a departure from previous outings, gone is the handheld game console form factor and in its place is a svelte USB-C stick with a nod to the first generation of EMF badges in its wave shape.

Physically the badge is formed of two PCBs that plug together with the LiPo battery sandwiched between them, the upper one carrying the display and battery while the lower holds the ESP32-S3 MCU and the various peripherals. These include a QMA7981 accelerometer, a QMC7983 magnetometer, and perhaps most intriguingly, an ATECC108A cryptographic accelerator. This last component gives it the potential to be a 2-factor authentication key, which we think is probably a first for a badge.

In use, the TFT display and joystick interface is usable, but hard to read for a Hackaday scribe whose eyes maybe aren’t as sharp as they used to be. Programming is via MicroPython, using an app format through the same online hatchery system that will be familiar to owners of other European badges. There are already quite a few apps, which we hope will help this badge have some longevity.

This is just the latest of a long line of EMF badges, of which the 2016 version is probably our favourite.

Hacker Camps Post-Pandemic, Electromagnetic Field 2022

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”

Looking Forward To EMF Camp: Teasing Us With A Schedule

As we gear up for a summer in the field, or more accurately in a series of fields, it’s time to turn our attention towards Eastnor Castle in the Western English county of Herefordshire, venue for the upcoming Electromagnetic Field hacker camp. Sadly we’ve got no badge to tease you with, but they’ve released a list of the talks that will fill their schedule. There are so many to choose from, we can only mention a few in this article.

We’ll certainly be taking the time to watch [Russell Couper] describe his electric motorcycle project. He’s no stranger to unusual bike builds, having given us a diesel machine at EMF 2016. Then of course there’s our own [Dave Rountree], who will be hacking the radio spectrum with GNU Radio. Sure to be an interesting talk.

One feature of this camp we’re very interested in will be CuTEL, a wired copper telephone network on the field. We’ll be taking along our trusty GPO 746 to be part of it of course, but for those without one, there’s [Matthew Harrold]’s talk on building a copper telephone network in a field.

Our cursory scan of the list finishes up with [Alistair MacDonald] on how not to start a hackerspace. We’ve seen our fair share of hackerspace drama over the years, so whether this one causes pain for ex-hackerspace-directors or not, it promises to be informative for anyone in the hackerspace world.

At the time of writing there are still some EMF tickets for sale, so if the beginning of your June is free we can heartily recommend it. To get a flavour of the event, read our 2018 review.

DIY Machine Enables PEMF Therapy On A Budget

We’re certainly not qualified to say whether or not pulsed electromagnetic field (PEMF) therapy will actually reduce your stress or improve your circulation, but there seems to be enough legitimate research going on out there that it might be worth a shot. After all, unless you’ve got a pacemaker or other medical implant, it seems pretty unlikely a magnetic field is going to make anything worse. Unfortunately commercial PEMF machines can cost thousands of dollars, making it a fairly expensive gamble.

But what if you could build one for as little as $10 USD? That’s the idea behind the simple DIY PEMF machine [mircemk] has been working on, and judging by its ability to launch bits of metal in the video below, we’re pretty confident it’s indeed producing a fairly powerful electromagnetic field. Even if it doesn’t cure what ails you, it should make an interesting conversation piece around the hackerspace.

While the outside of the machine might look a bit imposing, the internals really are exceptionally straightforward. There’s an old laptop power supply providing 19 VDC, a dual-MOSFET board, a potentiometer, and a simple signal generator. The pulses from the signal generator trip the MOSFET, which in turn dumps the output of the laptop power supply into a user-wound coil. [mircemk] has a 17 cm (6.7 inch) open air version wrapped with 200 turns of copper wire used for treating wide areas, and an 8 cm (3 inch) diameter version with 300 windings for when you need more targeted energy.

Some skepticism is always in order with these sort of medicinal claims, but commercial PEMF machines do get prescribed to users to help promote bone growth and healing, so the concept itself is perhaps not as outlandish as it might seem.

Continue reading “DIY Machine Enables PEMF Therapy On A Budget”

Nixie Shot Timer Adds Useful Elegance To Espresso Machine

Once you’ve ground the beans and tamped the grounds just so, pulling the perfect shot of espresso comes down to timing. Ideally, the extraction should last 20-30 seconds, from the first dark drips to the tan and tiger-striped crema on top that gives the espresso a full aftertaste.

[Marco] has a beautiful espresso machine that was only missing one thing: an equally beautiful shot timer with a Nixie tube display. Instead of messing with the wiring, [Marco] took the non-invasive approach and is using a DIY coil to detect the magnetic field of the espresso machine’s pump and start a shot timer.

An LM358-based op-amp magnifies the current induced by the machine and feeds it to an Arduino Nano, which does FFT calculations. [Marco] found a high-voltage interface driver to switch 170 V to the Nixies instead of using two handfuls of transistors. Grab yourself a flat white and check it out after the break.

The last Nixies may have been mass-produced in the 1980s, but never fear — Dalibor Farny is out there keeping the dream alive and making new Nixies.

Continue reading “Nixie Shot Timer Adds Useful Elegance To Espresso Machine”