Badge Life comes to HammerCon

By 1LT Conrad W. Franke

May 6, 2024

Badges have been commonplace at the annual national convention of the Military Cyber Professionals Association (MCPA), HammerCon, but those are typically military issued items worn as an official part of a uniform. The badges we are creating for HammerCon this year, however, are part of what many of us refer to affectionately as badge life. These badges, popularized in the hacker community, are fun ways to integrate technology and art into something wearable. Inspired by DEF CON, HammerCon is now utilizing such badges as the access control token for its attendees, a huge upgrade from the printed paper attendee badges used during the first two years of HammerCon [1]. This article recounts how we went from concept to reality in bringing badge life to HammerCon.

HammerCon Badge

The Concept

I make badges like this for fun. As a 17A Cyber Warfare Officer in the Vermont Army National Guard and proud member of the MCPA, I had this idea when I saw the initial announcements for HammerCon 2024 and reached out. I offered the general concept, showed some of my past work, and committed to making this happen for the community. We were able to negotiate an approach with the support of my employer and we got to work on collaborating on designs.

Example of previous work provided.

Starting this in late January had us at about 4 months before everything needed to be done, which really puts the pressure on. Starting this project, I already knew we might be behind. Therefore, some considerations were a higher priority than may have otherwise been the case, such as overall design simplicity. The simplicity was key, for this audience especially, since some may later take their badges into their classified workspace where transmitters and certain interfaces would not be allowed. Other important aspects were keeping it budget-friendly, manufactured in the USA, and lead-free. When I received a go for this project, I was excited, but I would be lying to say that my stomach did not crawl up my throat. This was, by far, the largest project I have taken on with the largest audience. With all of this in mind, I started working on our designs and brainstorming what I could.

Initial brainstorming of badges and add-ons.

How The Boards Are Made

To understand the following paragraphs, one has to understand how a PCB actually works and is made. A PCB is a printed circuit board and is a sandwich of different materials that come together. The layers (from middle to outside) start with a layer of FR4. This is a fibrous material that is layered and smushed with glue together to separate the top and bottom of the PCB. Multilayer PCBs use the same concept and place copper in between the FR4 layers to add more connections and add components to the PCB. Just outside of the FR4 layer sits a copper layer. This comes from the factory in a sheet that is glued on top of the FR4. Resistive material is then printed on the copper that is preserved and used as traces and power plane. The entire sheet is then dipped into a strong acid that etches away the copper that has no resistive material. This process is called etching. A PCB is then washed thoroughly and cleansed of the acid by quality control specialists for the next stage. 

If drill holes are required, the PCB goes through a specialized machine that spins at thousands of RPMs and quickly creates all the holes the PCB makes. These holes create vias (tiny metal-coated holes that route power to the other side of the board) or through-hole connections for PCB parts. After that, a layer of solder mask is applied to the board. In most cases, solder mask is an evergreen color. It is used in many computers and consumer electronics and is the cheapest to use due to its availability and consumer base. 

A UV light will cure the solder mask, and shortly after, a silkscreen needs to be added. Silkscreen is the white (or other color depending on PCB) lines and identifiers for components that engineers use to place parts. Resistors are identified by R, for example, and capacitors identified by C. Silkscreen is typically printed onto the board with an inkjet printer. Lastly, the board is inspected to ensure connections exist where they are supposed to. Then the boards are shipped, and parts are attached to the board. 

Design Considerations

Finding a circuit within budget was my top priority. I wanted something cool with expandability so a challenge coin or other boards could be attached to the badges. After looking around at a few circuits, a BC558 LED switching circuit was selected. The components are minimal, it is very easy to prototype, low risk of mistakes, and of course, it looks pretty cool in action. Adding an add-on port to this circuit made it a game-changer. The ability to add-on spurred a related project in designing a new challenge coin for the MCPA that could attach to the HammerCon badge as its source of power and meet the same types of requirements we integrated into our approach with the badge.

HammerCon PCB Prototype.

This circuit uses 2 BC558 transistors which fill caps regulated by a resistor, and when full, allow voltage to dump over the LEDs. The size of the resistors and capacitors control how fast the circuit fills up and empties. I kept the LED color green which was in our operating voltage of the circuit so additional components did not need to be added. The power source would be from a CR2032 coin cell battery commonly found in computers, watches, car keys, and other consumer electronics. After coming up with all of this, a prototype circuit was built. Shortly after, Zetier (my employer), decided to fund my fun and the HammerCon badges as a sponsor.

PCB designer for badges

After establishing a circuit, it was time to digitize everything into a schematic. A schematic is a visual representation of connections and components that go into a circuit and allow engineers to make changes and blueprint their work. The program I used was KiCad, as it is free and easy to use. Not to mention, the open-source community is very helpful. After making a few revisions in the schematic editor, I imported all of my data into the PCB designer of KiCad. This is where the real magic happens. All of the images, design patterns, copper traces, holes, and exposed metal were customized through KiCad's PCB designer. This took the largest amount of time, totaling around 2 months and 1 week to get the final product you have around your neck today. 

KiCad schematic design viewer for the badges

After completing the PCB in the designer, I outputted Gerber files, which the fabrication facility (also known as a fabhouse) receives. I then emailed Advanced Circuits among many other fabhouses and got a reasonable quote back promptly. Shortly after, 1000 badges arrived at our doorstep. As soon as USPS notified me that they had arrived, I ripped the box open and there they were. I ripped one out of the box and hooked it up and... one of the LEDs was not blinking. I panicked for about half a second and remembered that the LED that I put on the badge was not a working LED. I quickly desoldered the LED and replaced it and voila, the circuit worked as intended.

Shortly after, many helpful individuals wound up working on these boards, including during a soldiering party at Capitol Technology University, where HammerCon is held. And thank you to these people as I cannot solder 1000 of these together myself. Eventually, after a few weeks, the badges got to where they are now, worn by you (if you are one of the lucky members of this community able to attend our Con)! 

Badge Soldering Party

The Way Ahead

At the time of writing this article, I already know the HammerCon badges will be amazing because we already have them in-hand. We are in the final stages of designing the new MCPA challenge coin, which will be among the first anywhere across the broader national security community. The coin as a badge add-on opens up a whole new layer of interest with the badges that others can build upon with their own add-ons or coin display!

Coin Concept Prototypes

Over the course of this experience in collaborating on these projects with the MCPA, we see the potential for many others across the military cyber community to leverage PCB based badges, plaques, and coins. This is especially true given the need for new traditions in this relatively new community. Therefore, we are spinning up a new program of the MCPA where units can order their own items that we can help them design. These items help support the educational mission of the MCPA by integrating interesting and interactive technology into items that are largely stuck in the previous century. MCPA members can find more about this initiative on our intranet.

I cannot provide enough thanks for the support from my unit, the Billingsleys, MCPA, my company Zetier, and my family. I would not have built up the skills or received the support and guidance to complete this project without all of you. Thank you!

References

[1] Ian Leatherman’s 2023 CYBER article highlights the relationships between the MCPA and hacker communities, most notably with Jeff Moss (Founder of DEF CON) providing opening remarks for the inaugural HammerCon. Those interested in learning more about badge life can watch a short documentary on the topic here.

About the Author

First Lieutenant Conrad W. Franke is a Cyber Officer in the Vermont Army National Guard and a Cyber Engineer at Zetier. He is seen here with components of the HammerCon badges.