DIY at OFFZONE 2022: how to level up your conference badge

OFFZONE
6 min readJul 22, 2022
DIY at OFFZONE 2022: how to level up your conference badge

The badges for OFFZONE 2022 will be just as memorable as previous years. We promise to deliver a sleek design with plenty of interactive features.

Let’s briefly recount the evolution of the OFFZONE badge. At the last conference, we made it in the form of an interactive printed circuit board (PCB) designed as a 3.5-inch floppy disk. The board could be accessorized: participants could attach a display, IR receiver, and other interesting things right at the soldering zone at the venue.

Starting from 2020, we’ve been postponing OFFZONE, so the 2020 badge design has never taken flight 😔

Internals of the OFFZONE 2022 badge

This year, we decided to split the traditional badge functionality: now the conference badge will operate as a wallet for your Offcoins, the currency used at the event, while the tasks will be moved to a separate device. But this doesn’t mean that the badge is now plain vanilla. Its main features in 2022 are customization and the creation of add-ons with unique designs. This could have become reality back in 2020, but, alas… no need to spell it out for you here, right?

Every add-on starts with a connector. This is a four-pin plug that makes the thing connectable to the badge’s main board. And because we’re using a connector, there will be no need for any soldering. The main board will have at least 2 slots for add-ons, which can be hand made by any participant. When creating them, you will have to adhere to some technical limitations, which we will tell you further down the line.

An add-on doesn’t have to necessarily have a full-fledged circuit of microcontrollers, transistors, and other crafty electrical modules. If you’re not really into the intricacies of circuitry, you can get by with a couple of LEDs and an unusual form of your textolite board. Even with this simplistic design approach, you can still have your jolt of fun!

How to create an add-on

Here’s your step-by-step guide to designing your own add-on.

0. Read the requirements:

  • Maximum dimensions: 5 cm x 5 cm
  • Connector location: at the bottom and approximately in the center of your add-on
  • Maximum power consumption of the add-on electrical circuit: 100 mA
  • Solder mask colors: green, red, yellow, blue, black, or white
  • Screen print colors: red, yellow, blue, black, or white
  • Power supply for your electrical circuit: 3.3 V
  • Connection interface: I2C
  • PCB topology: single or double-sided, one conducting layer per side
  • PCB input data format: Gerber

For convenience, our colleagues abroad have standardized the add-on pinout and size. All this was jokingly called a “shitty connector.” It hurts to look at these specs, but anyway it has all the data you need to design your own add-on.

1. Come up with an idea. Your idea can be anything: a meme character, your personal symbol, a company’s logo, or even a cat’s nose. At its simplest, you can get away with just a ready image, preferably in a vector SVG or DXF format, and import it into the PCB design software. You may be better off if you use black-and-white images for import. Also, we advise you the graphics editor Inkscape to prepare your images for import.

Here’re some add-ons from DEF CON to inspire you:

2. Think of extra features if you need them

3. Choose your development toolset. At this stage, decide which computer-aided design (CAD) system you’re going to use. There’re tons of PCB layout software out there for all tastes and colors. Here’re the most popular and accessible tools: KiCAD, EasyEDA, DipTrace, and CircuitStudio. KiCAD is open-source and free to use. The other three are commercial products whose trial versions offer enough functionality to create your own add-on.

It’s difficult to give advice on the choice of any particular CAD system. Each has its pros and cons, so just play around with the options.

4. Learn the basic CAD features. All CADs have a fair number of tutorials with examples of use. Also, they all have a similar development pipeline: once you get the hang of a CAD system, you won’t have much trouble learning another one.

We would recommend that you practice PCB design as follows:

  • Use basic components to build a simple electrical circuit made up of a couple of LEDs.
  • Fill out the rules to check the topology.
  • Experiment with different options for solder masks, metallization, and screen printing in your PCB editor.
  • Try to import images to the board.
  • Figure out the mechanism for creating polygons and layout verification.
  • Lay out your first PCB.

5. Design your add-on board. If you’re already experienced in PCB development or have confident CAD skills, you can move on to laying out your add-on.

6. Export your files into Gerber, the manufacturing format.

After you’ve laid out the add-on board, you will need to perform a simple yet important step — export the printed circuit board project into Gerber files. This should render a group of files that is a layer-by-layer description of your board.

To view the resulting Gerber files, you can use Altium 365 Viewer:

7. Choose your production method: factory or toner transfer.

There’re quite a few Chinese factories out there: PCBWay, JLCPCB, ALLPCB, etc. As an upside, this gives cheap and quality results, as a downside, your PCB will take some time to arrive, as it will have quite the distance to travel. That’s why you might want to consider a local manufacturer.

The other, hardcore option is to create the add-on by yourself using the toner transfer or photoresist method. It’s hard, pricey and time-consuming, but captivating!

Here’re some boards made using toner transfer:

8. Order your PCB from a factory or make your own using toner transfer.

By now, you should have settled on the production method. Are you going with factory? Great, now you have to place your order. Typically, that includes filling out a form on the manufacturer’s website, uploading your Gerber files, and making the payment.

However, if you’ve chosen the path of a true samurai and decided to make the add-on board yourself, it’s time to stock up on the necessary materials and get to work. There’re tons of instructions and recommendations on the web for PCB etching, so you won’t get lost.

9. Stock up on cocoa and patience. At this point, there will be some PCB magic going on in the factory (if you chose contract manufacturing) or in your kitchen (if you opted for toner transfer).

10. Profit!

By this stage, you should have received your PCB from the manufacturer or completed your own. Well done! Examine the result carefully.

In case something didn’t work out or doesn’t match your original idea, panic not. Developing any PCB, or electronics in general, is a process of iterations, and an add-on is no exception. Fix the errors and repeat the order or manufacturing step. If you’ve reached this stage, you already know how to design a PCB.

And if you were able to achieve the desired result in the first attempt, congrats!

11. Come around to OFFZONE 2022 and show off your PCB.

Keep in mind that the third international conference on practical cybersecurity OFFZONE will be held on August 25–26. It will bring together security specialists, developers, engineers, researchers, lecturers, and students from dozens of countries. It focuses only on technical content dedicated to current industry trends. To learn how to participate, visit the event’s website.

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OFFZONE

International community conference for cybersecurity researchers and professionals. No suits, no business — only hardcore research.