DIY Mini Helical Antennas From Salvaged Co-ax Cable

[Mare] has a visual guide and simple instructions for making DIY mini helical 868 MHz antennas for LoRa applications. 868 MHz is a license-free band in Europe, and this method yields a perfectly serviceable antenna that’s useful where space is constrained.

A metric 5 mm drill bit makes a convenient core.

The process is simple and well-documented, but as usual with antenna design it requires attention to detail. Wire for the antenna is silver-plated copper, salvaged from the core of RG214U coaxial cable. After straightening, the wire is wound tightly around a 5 mm core. 7 turns are each carefully spaced 2 mm apart. After that, it’s just a matter of measuring and bending the end for soldering to the wireless device in question. [Mare] has used this method for wireless LoRa sensors in space-constrained designs, and it also has the benefit of lowering part costs since it can be made and tested in-house.

Antennas have of course been made from far stranger things than salvaged wire; one of our favorites is this Yagi antenna made from segments of measuring tape.

Europe Loses Six Minutes Due to Sagging Frequency and International Politics

You might be reading this six minutes early. Assuming that the Hackaday editors have done their job, this article should have appeared in your feed right on the half-hour. We have a set schedule to keep you supplied with the tastiest of hardware hacks and news. For some of you though perhaps there has been a treat, you’ve seen it and all the other stories six minutes early.

Have you perfected time travel? Sadly not unless there’s something you’d like to send to our tips line last week, but the culprit is equally fascinating. A dispute between Serbia and Kosovo has caused the frequency of the interconnected continental European electricity grid to drift below its usual 50 Hz figure for a sustained period, and as a result all clocks that use the mains frequency as a time reference have been getting ever slower.

How Can a Continental Power Grid Dip?

Think for a minute of a modern car on a hot day. When you turn on the air conditioning you will hear a slight dip in the engine revs as it accommodates the extra load. So it is with an alternating current power grid; a simple example is a power station supplying a city. In periods such as cold nights when the demands of the city go up, the result would be that the power station needs to work harder to satisfy it, and until that happens there would be a slight dip in its line frequency. Power grids compensate for this by increasing and decreasing the available generating capacity in real time, maintaining a mean frequency such that the “grid time” of a clock controlled by it matches an atomic clock as closely as possible over time.

Screenshot of Swissgrid live frequency data

In the case of continental Europe, grids across multiple countries are connected (PDF), and the task of maintaining that mean frequency falls upon Swissgrid which currently shows a sagging 49.976 Hz frequency. The time deviation of -346 seconds puts this close to a six minute loss and clocks running on this frequency will make you late to your next appointment.

It is at this point we leave the realm of electrical engineering and enter that of international politics, normally something far removed from Hackaday’s remit. It is fair to say that the history between Serbia and Kosovo is extremely delicate, and to understand some of the context of this story you should read about the war at the end of the 1990s. After the conflict the Serbian-majority region of what is now Kosovo refused to pay the Kosovan utility for its electricity, eventually leading to the Kosovans refusing to pay for that region’s share of the power received by Kosovo from Serbia. The resulting imbalance between demand and supply was enough to drag the supply frequency down across the whole continent, and though a short-term agreement has been reached the problem still remains on the grid.

Clocks and Mains Frequency

So if you are a continental European and you find yourself six minutes behind your British or American friends, don’t worry. We know that among our readers are people with significant experience in the power generation world, perhaps some of you would like to use your six minutes to give us a bit of insight in the comments. Meanwhile here at Hackaday we maintain an interest in the mechanics of power distribution even if some might say that it is Not A Hack. We’ve taken a look at utility poles, and examined how power grids are synchronised.

As for those slow clocks, the use of mains frequency to keep accurate time is quite brilliant and has been used reliably for decades. Tightly regulating grid frequency means that any clock plugged into an outlet can have the same dead-on accuracy for the cost of a few diodes. These clocks count the zero crossing of the alternating current. There may be moment to moment drifts but the power utility injects or removes cycles over the long term so the sum of crossings is dead on over the course of the day. It’s an interesting phenomenon to experiment with and that’s why we see it in microcontroller projects from time to time.

World Create Day: Hackaday Meetups Reach Europe and Africa

world-create-day-europe-africaWe are now just three days away from Hackaday World Create Day. On Saturday, April 23rd, the Hackaday community around the world will come together in real life to have fun, share their stories, and to do a little bit of engineering.

A few weeks ago, we put out the call for local meetup organizers and were overwhelmed by the response. The World Create Day events in Europe and Africa span pretty much from pole to pole with meetups in Salangen and Cape Town.

If you are near any of the events on the map, please join in the camaraderie on Saturday If you don’t see a marker near you, it’s not too late, you can still host your own meetup. Follow these easy steps to get your town on the map!

What can you expect from World Create Day? At its simplest, gather together and talk about solving a technology problem facing humanity. This can be submitted as your Challenge 1 entry for the 2016 Hackaday Prize. But many organizers have more planned. We’ve heard from groups who are hosting hardware show-and-tell, others have lined of speakers or workshops, and we always suggest hosting lightning talks where anyone at the meetup can speak for around two minutes.

Hackaday is made up of doers. It’s time we all got together and celebrated what that means. Don’t miss out this Saturday!

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Get Your Hackaday Belgrade Tickets Now

We have just opened up registration for Hackaday | Belgrade — a hardware conference on April 9th. Get your ticket now and make arrangements to visit Belgrade this Spring. Tickets are inexpensive, travel costs from other parts of Europe are very reasonable, the weather will be beautiful, and the all-day madness that we have planned will make you wish it were a week instead of just sixteen hours. These tickets will sell out so please share this post with your friends so they are not left ticketless.

Packed with Amazing People

mike
If you don’t recognize the name you will almost certainly recognize his internet persona: Mike’s Electric Stuff. He’s been regularly featured on the front page of Hackaday as he churns out a unique body of work like tearing down Flir’s low-end gear to discover it’s identical to their high-end offerings.

Hackaday is a global community and that is what makes Hackaday | Belgrade spectacular. We are still accepting proposals for talks through February 15th but haven’t yet made all of the decisions regarding presenters — you should submit a proposal! We’ll publish an article about all of the presenters once we have wrapped up the call for proposals. Expect to hear back about this around February 22nd.

One thing I am very excited about is that Mike Harrison will be at the conference. His talk will cover his exploration of an absurdly expensive and complicated relic which was used in the 1950’s for large-format video projection. Mike’s ability to unlock understanding of complex (and awesome) electronics is quite amazing; this talk is not to be missed. But Mike is just one of a dozen presenters from all over Europe. Several members of the Hackaday crew will be on hand and the venue will be packed with hundreds of fellow hardware hackers. You won’t want to miss this.

You Will Hack This Badge

hackaday-belgrade-badge-prototypeThis is the first Hackaday event where we have an active electronic badge. Voja Antonic has been hard at work with the design and just published the first details a few days ago.

The central feature of the badge is an 8×16 LED matrix driven by a PIC microcontroller. It’s running a USB bootloader which will let you flash your own custom code without needing a programmer. We were speaking with some of our friends over at Microchip regarding the bootloader and they offered to supply all the microcontrollers for the badge, an offer we were happy to accept.

Voja has already programmed the first demo application seen here, it’s Tetris written in assembly language. Impressive!

We were overwhelmed by the popularity of badge hacking at the Hackaday SuperConference last November. You can bet that badge hacking will be one of the most popular activities at Hackaday Belgrade. I have written a hardware emulator to work on some animations. It uses the SDL2 library to display the LED matrix and take three button inputs (the final badge design will have four buttons arranged in up/down/left/right configuration). Our hope is to host a demoscene competition that is open to anyone, whether you can attend the conference or not. More on that later.

Live Music and Hacking

As the evening sets in and the talks wind down, we have lined up bands and DJs to take the stage and carry us well into night. You won’t have to stop the badge hacking or anything else that you’re into, but you won’t have to solder in silence either.

As you can tell, this conference goes way beyond talks. This is hardware culture and you’ve just got to be there. Running from 10am until 2am, there’s more than enough to keep you occupied for one day. But make sure to hang out on the event page to get inside information on other non-formalized social events that will happen the night before and the day after. See you in Belgrade!

Hackaday Europe: Call for Proposals

Hackaday is coming to Europe in April. The world’s most superb conference on hardware creation starts with you. Please submit your proposal to present a talk or workshop at 2016 Hackaday | Belgrade, Hackaday’s first-ever European conference.

Put it on your calendar: Saturday, April 9th in Belgrade, Serbia. We have a lineup spanning from 10am to 2am, and we’re building on the best of the inaugural SuperConference we held last November: a single track of hardware talks which will run concurrently with a set of hands-on workshops. The surprise hit from that conference was badge hacking, which will be expanded and extended into the wee hours of the morning. While that is in progress, a party with two stages will spin up with performances by Infinite Jest, Grupa TI, and DJ sets.

Tickets go on sale the first week of February. Voja Antonic, who does amazing work with PCBs and badge designs, is building the conference badge. The cost of the admission will be just enough to cover the cost of the badge. We’re keeping the admission cost so low to help offset your travel costs. Belgrade is gorgeous in April, and getting there from other parts of Europe is very affordable. This event will sell out so get organized and make sure you and your fellow hardware hackers get tickets early.

Many of the Hackaday crew will be on hand. We’re likely to have a less-formal meetup (hangover brunch?) on Sunday. Check out the Hackaday | Belgrade planning page to discuss this and learn more about the conference as it comes together. See you in Belgrade!

Hackaday Prize Worldwide: Zürich on Thursday

Join us for a Meetup Thursday the 24th of September in Zürich, Switzerland. We’re co-hosting a meetup with FabLab Zürich and we are excited to see you!

Doors open at 18:00 on Thursday, 24 September. We’ll have some food and drink, project show and tell, and time to hang out and get to know each other. This is a free event but please RSVP to let us know you’re coming.

Bring the project you are working on to show off, everyone loves to see projects regardless of what stage they’re in. Many times, showing your project and talking about it pushes your project forward; “oh hey, I have an extra RN42 BT module you can have” or “I already wrote a driver for that chip and it’s on github”. Showing your project to others can also inspire someone else to make their own project based on your awesome idea. I’ve been motivated many times to start a project because of what I saw someone else make.

Germany Too!

This Zurich meetup isn’t the only chance to connect with Hackaday in Europe. Next week, we’ll be in Berlin! We’re co-hosting a Berlin Meetup with Vintage Computer Festival organizers in the evening after Berlin Maker Faire and the Vintage Computing Festival. VCF have planned food and drink, a live band or two… chip tunes! It will be on October 3rd, and [Elliot], [Sophi] and [Bilke] will all be there.

Munich: Help Plan Hackaday’s First European Event

On Thursday, November 13th we’ve rented a huge hall in Munich, Germany and plan to host a hacking event followed by a celebration.

You need to take the day off of work and join us. Better yet, convince your boss that this is professional development and that attending is good for the company!

We’re not taking the space shuttle across the pond, this illustration reflects the connection with The Hackaday Prize. This trip will mark the end of the contest and the unveiling of the Grand Prize winner.

 

What do *you* want to hack?

The big question we have right now, is what kind of hands-on hardware hacking do you want to do? We published a page over on Hackaday.io to discuss the possibilities. Let your imagination run wild and we’ll do our best to make it all happen. We know from James’ hackerspace tour last year that there are a ton of Hackaday community members within reasonable travel distance from Munich. Here’s our chance to get everyone together for an Epic day of building and night of partying.