Thank you for running First Traces! I (@Brenden on slack) have spent so much of my time working on this workshop, and the traces program in its entirety and I hope that you and your participants have a better time running this workshop than i did making it! (many weekends spent working, and enough caffeine to take about 5 years of my life) Many thanks to @Noah Walsh for testing this workshop with this club, @jps for sponsoring this program, and @aahil for stepping away to work on his other programs, and for allowing me to pick up running traces! Now on with the guide!

These premade guides for this workshop do not prepare for every way that your participants will manage to fuck it all up, so i recommend that you go through these guides yourself, and learn about the tools your participants will be using, WokWi, EasyEDA, and The Arduino IDE. I also recommend that you familiarise yourself with the ordering process for JLCPCB, (or a different PCB manufacturer if it is cheaper for you or more available in your country)

What First Traces is

Six sessions that take a group of students from "what even is a microcontroller" to a custom PCB they ordered for real.

1. Session 1 — Microcontrollers & Your First Circuit — build and simulate an LED circuit in Wokwi.
2. Session 2 — Wiring Up & Writing Code — write the code that drives it.
3. Session 3 — Breadboards & Code Basics — the four lines of code everyone will actually use, and how a breadboard is wired.
4. Session 4 — From Simulation to Breadboard — the same circuit, on real hardware.
5. Session 5 — From Breadboard to PCB (EasyEDA) — the same circuit again, as a board layout.
6. PCB Guide — export the Gerbers and hand them to you to order.

Every session ends with something running, and the program ends with a board in each participant's hands. That's the hook — sell the club on the fact that participants leave with real hardware, not a certificate.

The first three sessions need nothing but laptops. The hardware only shows up at session 4, which means you can start the program while your parts are still in the post.

Who this is for

• Club leaders running Traces for their own club, usually 8–15 participants. Above about 15 you stop being able to help everyone in the room, so i would recommend to get another leader at that point
• Students with no electronics background. The sessions expect no experience

Before you start

Run the whole thing yourself first. Do every session on your own machine, start to finish, including the PCB order. These guides do not prepare for every way a participant can break their circuit, and the only way to find out how yours breaks is to break it yourself. Do the drills in this section before your first session, not during.

Get into #first-traces-help on Slack. Programme questions, kit questions, and "is this normal" questions all belong in the #first-traces-help channel on Slack. The people who wrote these guides are in there and they know the answers faster than you can search.

Make the accounts before the first session. Tell participants to sign up for Wokwi and EasyEDA and confirm the email before session 1. Account creation eats fifteen minutes of a session if you leave it to the room, and half your group will hit a verification email at the same time. Wokwi is needed from session 1; EasyEDA isn't until session 5, so session 4 is your last clean warning.

Know the ordering process. PCB Guide sends participants to you with a Gerber file, not to a checkout. Read the JLCPCB order flow end to end, and find out what your local alternative costs and how long it takes, before anyone hands you a file.

Check the room. The first five sessions are all web-based, so you need:

• A projector or screen for demoing your own circuit at the front.
• Reliable Wi-Fi for Wokwi, EasyEDA, and the Arduino IDE downloads. Test it on the actual meeting machine, not on your phone.
• Power outlets for everyone, and enough table space for a breadboard and a laptop side by side.
• One spare Arduino Uno and a spare breadboard for you. You'll want to demo something broken on purpose, and you don't want to be fumbling while you do it.
• The original slides if you'd rather present from those than from the guide.
• For the soldering session at the end: a soldering iron per two people at minimum, solder, flux, and somewhere ventilated. See The soldering session.

The kit

You will get about $15 to $20 for your Arduino kit, this guide is designed for a kit like this. If you need to get a different kit you may need to change the guides/edit the slides for different components

Everything the guides actually touch, per participant:

Two things the guides mention that sessions 1–4 never actually build:

• 9V battery snap and DC barrel jack pigtail, and ceramic disc capacitors — these appear in the session 5 footprint reference as optional board furniture. Nothing earlier in the program introduces them and the LED circuit doesn't need them.
• Buttons are offered as a session 2 stretch task and again in session 5, but no session teaches a button circuit.

So: hand out the full kit and let participants use the parts they want, but don't plan a build around the battery snap, and don't promise a button exercise unless you're going to teach it yourself. If your kit is missing the buttons entirely, sessions 2, 4 and 5 still work — the stretch task just becomes "design something with the LEDs".

Running the sessions

Aim for about 40 minutes a session, and try to keep the gap between them small, once a week is probably fine, but with more of a gap in between, your participants might start to forget things.

A realistic run looks like this. Dates are relative — count back from your last session, not forwards from today:

Two rules for moving this around:

• Sessions 1–3 are software. If your parts are late, run them anyway and shift the whole schedule. Don't try to run 4 without a kit.
• Don't leave a gap between 4 and 5. The pin numbers people write down in session 1 are the same ones they wire in session 4 and enter in EasyEDA in session 5. Skip a fortnight between those and half the room will be debugging the wrong pin.

Session 1 — Microcontrollers & Your First Circuit

This session is all on the web simulator. No hardware, so it's the easiest session to run and the easiest to recover from.

• Get the room on Wokwi and onto an Arduino Uno before you start talking. If you're demoing, use the same "start from scratch" path they will.
• The pin diagram does a lot of work here. Two or three minutes naming GND, 3.3V, 5V, digital, and analog is cheaper than twenty minutes of debugging later.
• The resistor is where the room goes quiet. Ohm's law, V = IR, 3.3V at 30mA, therefore 1000Ω. If someone asks why 30mA, "because that's the safe maximum for the LED" is a complete answer.
• End with a working blinking LED in Wokwi. Wokwi generates a starter sketch for you, so it blinks before anyone has written code — that's fine, session 2 is where they take it over. Anyone who doesn't have one by the time you move on should pair with someone who does rather than fall behind.

Session 2 — Wiring Up & Writing Code

• The room meets setup and loop for the first time. Draw them on the board and leave them there for the rest of the program.
• The stretch task is deliberately open-ended: "design something with the buttons and LEDs in your kit, and find code online." Have two or three ideas ready, and expect to spend most of your time being a search assistant.
• Pin numbers from now on matter. The LED was wired to a pin in session 1, and that exact pin is the one they wire in session 4 and enter in EasyEDA in session 5. Make everyone write their pin numbers down where they'll see it again — a photo of the Wokwi sketch in their phone is enough — or you'll rebuild half the room's breadboards from scratch next week.

Session 3 — Breadboards & Code Basics

Still a simulation session, so it's a good week to run if parts haven't landed.

• This session is for participants to work independently, go around the room and help where you can, but don't lecture them
• If a participant doesn't have a finished circuit by the end, they will not get through session 4 — pair them up rather than carrying them.
• This is the natural place to hand out kits if they've arrived, so people can look at the parts before they're needed.

Session 4 — From Simulation to Breadboard

The session that decides whether the rest works. Expect to spend most of your time on the floor.

• Demo the whole build on your own board first, at the front, at walking pace. Then hand out kits. Then circulate.
• The three failures you'll see, in order of frequency:
  1. LED backwards. Long leg is the anode, and it goes through the resistor. If they didn't get it in Wokwi they won't guess it here.
  2. Both LED legs in the same row. The LED is shorted, and the whole row is the anode. The guide says "two different rows" — say it out loud.
  3. The code and the breadboard disagree. The pin in the sketch isn't the pin they wired to. This is the one session 1's "write your pin numbers down" note prevents.
• Have a known-good Uno on the floor with a sketch loaded, so you can swap a board in a couple of seconds and make sure their board isn't broken

Session 5 — From Breadboard to PCB (EasyEDA)

The hardest session, and the one where the room is most likely to give up on themselves.

• Get the .epro2 project file ready and shared in advance. PCB Guide tells participants their leader provides it; if you don't send it before the session, the first twenty minutes will be thrown off. There is currently no public link to the file — ask in #first-traces-help if you don't already have it.
• Reassure them about the ratsnest. The blue lines aren't an error state, they're just "these pins still need connecting", and half the room reads them as a broken board.
• DRC is where the session stalls. Push people to fix every red marker before they leave, and remind them what the markers mean: traces too close, a short, or an unconnected net. Unconnected nets are the most common one, and they mean a missing wire in the schematic.
• 45° corners and thicker power traces are guidance, not rules. Don't let a perfectionist argument eat the session.
• The last ten minutes are the deadline: everyone exports their Gerbers and sends them to you. Do not say "we'll do it next week." Get the files in the room.
• Session 5 mentions a battery snap, a barrel jack, capacitors and buttons as optional parts. Nothing before this session built them. Say out loud that they're optional, or you'll have half the room trying to lay out parts the circuit doesn't use.

The PCB order

Once the files are in, the work is yours.

1. Collect every Gerber file, and keep the names with the participant names. Somebody will send you gerbers(3).zip and you'll want to know whose it is.
2. Spot-check before you pay for anything. Open each file in a Gerber viewer or back in EasyEDA and confirm the board outline, both copper layers, and the silkscreen are all there, and that nothing is left unconnected. One bad zip means one dead board and three weeks of postage.
3. Order the whole batch together. Two layers, 1.6mm FR-4, and the standard defaults are fine.
4. Round up to JLCPCB's minimum of 5 per design and treat the remainder as spares rather than deliberately ordering spares. You will need them: a handful of participants will pull a pad off, bridge two traces with a stray blob of solder, or discover some other way to fuck it up. Keep the spares; they become the replacement stock at your soldering session.
5. Pay from the program budget and keep every receipt. You'll be asked for them at the end.
6. Tell participants the delivery estimate the same night you order. Nobody should find out three weeks later from a silence.
7. Ship the boards to participants who can't get to a soldering session, or hold them all for one.

While you wait

Production plus shipping is realistically three to four weeks. Say so at session 5, then give the club something to do, because three weeks of nothing is how people drop out.

Things that work:

• A build night. Anything with an Arduino and a button is a fine follow-up, and it's the exercise session 2 never taught.
• A show-and-tell of everyone's board designs side by side, straight out of EasyEDA — no hardware needed.
• A second PCB run: the stretch task is "change the circuit", so the people who finish early can order a second board and have it made with the first batch.

The soldering session

The boards arrive unsoldered. Somebody has to put the components in, and that's a session with its own setup.

What you need per two participants:

• A temperature-controlled soldering iron, and a sponge. An iron between two people is what makes this take four hours instead of two.
• Leaded solder, flux, and a few desoldering wicks for mistakes.
• Side cutters and needle-nose pliers. Cheap ones are fine.
• Something to put finished boards in. An egg carton is a legitimate answer.

Before you start: have everyone build their circuit on a breadboard one more time with the parts that are actually going on the board. Someone whose parts only work because of a bad breadboard row finds out three weeks later otherwise.

The order of operations, which is the same for everyone:

1. Insert the pin headers, LED, and resistor. Through-hole parts go in from the top of the board and are soldered from the bottom.
2. Clip the legs flush with the board, from the top, after soldering.
3. Solder the joints: heat the pad and the leg together, then feed solder to the joint — not to the iron. A cold joint is grey and grainy, and it will fail later.
4. Test on the bench before anyone plugs in a USB cable. If the LED lights with the board on the bench, it's done.

Safety, and say it out loud: irons are hot enough to burn and the smoke is not good for you. Solder over a tray, not in your lap. Wash your hands before you eat. Nobody touches an iron they haven't been shown how to hold.

Timing: about 90 minutes for a room of eight people who've done it before, two hours if none of them have. Leave the last twenty minutes for testing and for the boards that don't light up.

Grants and budget

Clubs will receive $30 for each working finished PCB shipped by a participant. You will only get your funding after your participants have shipped projects, so you need to have enough cash to pay for the hardware before running this workshop.

• TODO — the amount is confirmed, the mechanics aren't. Add how a participant's grant is claimed (which form, submitted to whom), the budget code, and the deadline. Say explicitly whether the $30 covers kit costs as well as the PCB order — a $15–$20 kit plus a board house order against a flat $30 is currently ambiguous.
• Don't quote a deadline to your club until you've confirmed it. A grant deadline that moves is much worse than no date at all.
• Spend the grant on what the guide needs and nothing else. If your club wants a soldering iron, a bench supply, or spares beyond the first batch, ask in #first-traces-help first.
• Every participant should finish. The grant is tied to people getting to a board, so if someone's stuck at session 4, spend the extra session on them.

Troubleshooting

Checklists

Before session 1

• Run every session yourself, end to end
• Kit enough people, plus spares
• Get the .epro2 file and the slide deck to hand
• Confirm everyone has a Wokwi account
• Test the room's Wi-Fi and projector
• Book a soldering session for roughly three weeks after session 5, and check you can get enough irons
• Post the guide links in your club's channel, not just the session time

Every session

• Demo your own build first, at the front
• Circulate instead of lecturing — sessions 4 and 5 are floor time
• Note what got stuck, so the next session can start there
• Take a photo of the room working, and post it

After the last session

• Every participant has sent you a Gerber file
• Spot-check each file before ordering
• Order the batch in multiples of 5, keep the remainder as spares, and keep the receipts
• Tell participants the delivery estimate the same night you order
• Claim the grant, per the process above
• Post the finished boards somewhere public

Soldering night

• Everyone has tested their circuit on a breadboard with the parts that are going on the board
• An iron per two people, plus solder, flux, cutters, and somewhere ventilated
• Every board tested on the bench before it goes home
• Spares on hand for the boards that don't light up

Where to get help

• #first-traces-help on Slack for anything program-related. This is the fastest route to a real answer.
• The Hack Foundation if the question is about the grant itself — the claim form, the budget code, or the deadline — rather than about the workshop.
• Me (@Brenden) if none of that works. Please come with what you tried first — it's much easier to help, and I write the guides, so I know which step you got past.

Original slides: Traces: Guide Slides!