Introduction: HackerBox Soldering Workshop

Greetings to HackerBox Hackers around the world.

This Instructable contains tutorials on soldering electronics projects and multiple hands-on lessons using the HackerBox Soldering Workshop, which can be purchased here.

What is a HackerBox you ask? HackerBoxes is the monthly subscription box service for DIY electronics, computer technology, information security, and hacker culture. To automatically receive the monthly HackerBox right in your mailbox with a $15 discount each month, subscribe at and join the revolution!

Building and experimenting with electronics, while very rewarding, can be tricky, challenging, and even frustrating at times. When you persist and enjoy the adventure, a great deal of satisfaction can be derived from this hobby. Always start with a sense of adventure, hacker spirit, patience, and curiosity.

The point of soldering practice projects is to gain exposure to soldering and get some practice hours in. While it is rewarding to complete a project with a working artifact in hand, don't be to hard on yourself (or anyone else) if you burn up an LED, shoot a resistor across the room, lift a pad off a PCB, or let the smoke out of an integrated circuit.

As we like to say, the goal is progress, not perfection. Take each step slowly, mind the details, and don't be afraid to ask for help. Also, there is a wealth of information for current and prospective HackerBox members in the HackerBox FAQ.

Step 1: Learn to Solder With the HackerBox BadgeBuddy

This video provides a detailed introduction to soldering and demonstrates assembly of the HackerBox BadgeBuddy. The BadgeBudy is simple and fun "introduction to soldering" kit. HackerBoxes is proud to have produced several thousands of BadgeBuddy kits for promoting our hobby at the DEF CON hacker conventions in Las Vegas.

The BadgeBuddy is a blinky mini-badge PCB that can be hung from a conference lanyard, backpack, purse, belt, etc using the included ball chain. The BadgeBuddy uses an improved style of self-cycling rainbow LEDs for a reduced BOM with no external control circuitry required. This makes for an interesting result that is still simple enough for a first time soldering project.

BadgeBuddy Assembly Notes:


Step 2: Sixty Second Countdown Timer Soldering Kit

The Countdown Timer Kit has a lot more components than the BadgeBuddy, but it uses the same basic "through hole" soldering techniques. It provides a lot of solder points to practice on.

For beginners, most errors come from interchanging two different parts that look similar or from putting a part on the PCB backwards or even on the wrong side of the board. For best results when working on a larger project with more parts, start by sorting out all of the components to be sure which one is which.

Always note the orientation markings on parts where that is relevant. That is pretty much everything aside from resistors and very small capacitors. Integrated circuits, diodes, and larger capacitors are almost always "polarized" and only work in one orientation. Electronics are full of smoke, and if you place components the wrong way around, there is a good chance that you will let that smoke out. Unfortunately, there is no way to put the smoke back in.

Step 3: Countdown Timer Schematic

The Countdown Timer uses a 555 Timer Chip to generate a clock signal that pulses once every second. This signal clocks a chain of two CD4017 Counter Chips. The outputs of the counter chips drive sixty LEDs (one for each second of a minute) through a CD4069 Hex Invertor (datasheet).

Step 4: Countdown Timer Assembly Notes

1. Resistors and Diode

Insert the resistors (small beige blobs with colorful stripes). Note that there are six different values of resistors. You can verify each resistor value from the colorful stripes using a color code chart (or smartphone app). You can alternatively measure the resistance with a meter. Better yet, do both!

Once you determine the vale of a resistor, but the resistor into the pair of PCB holes marked with that value.

Resistors are not polarized, so they can be inserted either way around, but remember that the values cannot be interchanged.

Unlike resistors, diodes ARE polarized. They only conduct in one direction, which is actually their whole point of existence. Diodes are one-way valves. Orient the diode D62 such that the black band on the diode aligns with the thicker line on the PCB silkscreen as shown.

2. Transistors

For the four transistors, note that each has a flat side and a rounded side when viewed from above. The PCB silkscreen also shows a flat and rounded outline for the transistors. Be sure to populate each transistor according to this orientation. They will not work if reversed.

3. Capacitors

There are two smaller ceramic capacitors, these can be inserted either way around (they are not polarized) and they have the same value. The three larger electrolytic capacitors are polarized must be inserted with their longer (+) leads into the square pad on the PCB. Note that there are two different values of electrolytic capacitor: C4 is a 220uF while C1 and C3 are 10uF capacitors.

4. On-Off Switches

Align the notch on the white portion of the button with the similar marking on the PCB silkscreen. The notch much be oriented towards the bottom of the PCB as viewed from the top.

5. Momentary Switches

The momentary switches S2 and S3 will only fit into the PCB in two orientations which are 180 degrees opposite (the leads will not fit in if the buttons are turned 90 degrees). Either of the orientations that easily fit will work fine.

6. Buzzer

Note that the buzzer has a positive (+) marking on the device itself and on the PCB silkscreen. Match them up.

7. Integrated Circuits

Similarly, align the little half moon "notch" on each IC with the similar marking on the PCB silkscreen. Try not to overheat the chip pins. It should only take 2-3 seconds of contact to flow solder on each connection.

8. Power Supply Socket

Insert the barrel socket as shown. A trimmed lead from one of the resistors (or any other thin wire) can be wrapped over and soldered into place to provide for mechanical reinforcement preventing the socket from lifting up when the cable is inserted.

9. Light Emitting Diodes (LEDs)

LEDs are polarized and must be inserted with their longer (+) leads into the square pad on the PCB.

10. Party Time

Step 5: Countdown Timer Operation

  • The power cable can provide 5V from any USB socket
  • The POWER button is an on-off switch
  • Press the START button to begin the countdown
  • Press the PAUSE button to pause the countdown
  • LED D61 blinks while the countdown is paused
  • Press PAUSE again to continue the countdown
  • Press STOP to reset the counter
  • The buzzer will sound when the countdown ends

Step 6: Soldering Surface Mount Technology

Surface mount technology (SMT) is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). SMT has largely replaced the traditional through-hole technology method of fitting components with wire leads into holes in the circuit board. Both technologies can be mixed on the same board, with the through-hole technology used for components not suitable for surface mounting such as connectors or larger transformers. (wikipedia)

SMDs can be hand-soldering and reworked with a little practice, care, and the right tools. Learn all about it from Dave in EEVblog 186.

In production, SMT soldering is not done by hand, but lends itself perfectly to solder paste reflow as discussed in EEVblog 415. If you just can't get enough solder reflow, this video features Ben Heck fabricating a DIY reflow system from a salvaged toaster oven.

Step 7: SMT Kit - Introduction

This introductory SMT Kit implements an LED Sequencer. Before starting the kit build, carefully review the Bill of Materials (BOM) and Schematic Diagram. The BOM is a list of all components. The schematic illustrates how each component is connected to the others. While not specifically related to this particular kit, this tutorial describes the operation of the LED Sequencer circuit.

Keep in mind that this is intended to be a practice kit. Soldering tiny parts takes a lot of practice, so don't stress over any mistakes. Just meet the project at your current skill level. If you have no experience at all, perhaps your goal should simply be to try 10-15 of the 0805 parts with the hopes of getting a couple of them right. Only if you are experienced, or just have a lot of dexterity and good vision, should you go into this kit expecting to come out with a fully functioning board. Proper LED Sequencer functionality is just a cherry on top. The primary intention is to practice soldering and get some exposure to SMT.

Note that all of the components on the sequencer side of the PCB that have two components are 0805 sized. That should make them easy to separate from the others. The others that remain when the front of the PCB is complete are larger (1206) and smaller (0603 and 0402) sized components. These can be used for practice on the back of the PCB. The smaller surface mount components can be quite challenging, but give it a shot. Very tiny SMT components are usually not soldered by hand in practice.

Step 8: SMT Kit - Assembly

Watch an Assembly Video.

Carefully note the orientation of the four orange diodes and the 15 LEDs. The black band on the orange LEDs should be oriented towards the chamfered edges of the outline on the PCB silkscreen as shown.

Markings for the LEDs vary, but generally a green tint on the lens marks the cathode, or negative, side of the LED. The silkscreen has a "+" indicator on each LED footprint designating the anode side of the LED. Also, the bottom of the LED may have an arrow or tee that points toward the cathode. Most multimeters have a diode mode that can also assist in identifying polarity and color of the LED.

Once assembled, the SMT board can be powered with anything between 3V and 12V D.C. This may be provided from various arrangements of batteries or using the USB power supply module.

Step 9: USB Power Supply

The CE009 module is a very simple, but very nice, little power supply. It is useful for powering any number of circuits requiring 5V and/or 3.3V.

The CE009 supplies 5V directly from a USB source. It also includes an AMS1117 (datasheet) low-dropout (LDO) regulator to generate 3.3V from the 5V supply. The AMS1117 LDO regulator should be able to supply a maximum of 1100 mA on the 3.3V rail, but it's wise to keep the current draw below 800 mA for safety and stability.

Step 10: LED Fidget Spinner Soldering Kit

Step 11: LED Fidget Spinner - LEDs and Resistors

Mount the eleven 100 Ohm resistors and the eleven LEDs.

The resistors are not polarized and may be turned either way.

However, be sure to observe the proper orientation of LEDs.

Order the colors of the LEDs to match the patterns generated in the example images, or select your own.

Step 12: LED Fidget Spinner - Integrated Circuit

Carefully note the pin one indicator on the Integrated Circuit and orient it closest to the notch on the PCB silkscreen. Both the small ceramic capacitor and the 10K ohm resistor may be turned either way, but do not interchange them.

Step 13: LED Fidget Spinner - Final Assembly

Note the orientation of the coin cell battery clips. Solder them from the opposite side of the board. Slide the coin cells under the clips from the outside edges of the PCB.

Once the coin cells are in place, verify that the PCB lights up when the power button is pressed.

Position the bearing and then the PCB into the plastic housing.

Close up both sides of the housing and tighten the three tiny screws to fix everything into place.

Step 14: Hack the Planet

We hope you are enjoying this adventure into electronics and computer technology. Reach out and share your success in the comments below or other social media. Also, remember that you can email anytime if you have a question or need some help.

What's Next? Join the revolution. Live the HackLife. Get a cool box of hackable gear delivered right to your mailbox each month. Surf over to and sign up for your monthly HackerBox subscription.