A soldering practice kit is one of the best ways to learn hands-on soldering and electronics assembly. This simple flashlight project is an ideal electronic project for beginners and serves as a practical soldering project for adults as well. The kit includes a PCB and all the necessary components to build a working flashlight that works from a single 1.5V cell — no programming or advanced tools required.
Let’s walk through how to complete this beginner-friendly DIY soldering project, including a component reference table and best practices for successful soldering.
Table of Contents
- What Is Included in This Soldering Practice Kit?
- Tools For Assembling the Flashlight Soldering Practice Kit
- How to Assemble the Flashlight Kit
- Tips for Soldering Practice Kit Success
- Frequently Asked Questions About Soldering Practice Kit
- Conclusion
What Is Included in This Soldering Practice Kit?
This flashlight soldering practice kit contains a single-sided printed circuit board and basic electronic components. It’s designed for through-hole soldering and operates from a single 1.5V cell or battery.
The electronic flashlight kit used in this tutorial has the markings EQKIT, 18122F-Y76-200214, FLA-1, and 161007 on the circuit board, or printed circuit board (PCB) as shown in the following image.
Kit Parts and Parts List
The following image shows all the parts of the kit. Refer to this image while looking at the table that follows.
Here’s a breakdown of the components and their corresponding PCB labels:
| Qty | Part | Notes | Type |
|---|---|---|---|
| 1 | Plastic Enclosure | Plastic enclosure that is cut out to fit the finished PCB and battery. Cut-outs are on either end of the enclosure for the switch and LED. | Enclosure |
| 1 | Flashlight Circuit Board | Flashlight printed circuit board. | PCB |
| 1 | YX8115 | LED driver IC or integrated circuit in a TO-92 package. | Integrated Circuits |
| 4 | 47Ω | 47 ohm resistor. Value and number of resistors may vary per kit. Only one 47Ω resistor is used to build the flashlight. Others are for soldering practice. | Resistors |
| 1 | Switch and Button | A switch with separate plastic button that clips to the top of the switch. | Switches |
| 2 | Spring Terminals | One positive and one negative spring terminal that form the battery holder when soldered to the PCB. | Battery Spring Terminals |
| 1 | 8mm White LED | White LED (Light Emitting Diode) that produces the light from the flashlight or torch. | LEDs |
| 1 | 47µH | 47µH inductor or coil. | Inductors |
Powering the Flashlight Circuit
The only additional item needed to operate the kit once built is a single 1.5V AAA cell or AAA battery. A 1.2V AAA rechargeable cell or battery also works.
Ordinarily a 1.5V cell can not light up an LED, as the voltage is too low. The components in the flashlight circuit boost the voltage to a higher value. As a result, the circuit is able to switch the LED on.
Once assembled, this circuit powers a single white LED via a simple switch. It’s a straightforward soldering practice layout, making it ideal for both new learners and hobbyists looking to refresh their skills.
Tools For Assembling the Flashlight Soldering Practice Kit
Use a soldering iron, solder wire and a helping hands magnifier to build the kit, as well as a pair of wire cutters, and small needle nose pliers. A helping hands magnifier or similar clamping tool is essential for this project in order to solder the battery spring terminals to the board.
How to Assemble the Flashlight Kit
Before soldering the electronic flashlight kit, beginners can solder some of the spare resistors to the practice part of the circuit board. This is the grid of holes near one edge of the circuit board. There are some additional 47Ω resistors in the kit that can be used for soldering practice. Just make sure that there is one resistor left to solder to the actual flashlight circuit.
How to Solder a Resistor
A general rule when soldering an electronic kit is to solder the lowest profile components to the board first. If taller components are soldered first, then it can be difficult to fit the lower profile components to the board afterwards.
In this electronic flashlight kit, the resistor is the lowest profile component, so it is soldered first. Before soldering the resistor, it must be properly identified. Some kits come with four 47 ohm resistors, while others may come with two 47 ohm resistors and two resistors of a different value. Be sure to have one 47 ohm resistor left over after practicing to use in the actual flashlight circuit.
Identify the Resistor
The value of a resistor is read from the colored bands on the resistor. A 47 ohm or 47Ω 5% tolerance resistor has the color bands Yellow – Violet – Black – Gold as can be seen in the following image.
Yellow has the value 4, violet has the value 7 and black has the value 0. Gold shows that the resistor has a 5% tolerance, which means that the actual value of the resistor is between 47 ohms plus 5% and 47 ohms minus 5% for a 47 ohm resistor.
Step-by-Step Assembly Instructions
Refer to the following image to place the components correctly on the circuit board.
Follow these steps to complete the soldering practice kit:
- Insert Resistor (R1):
Cut a resistor from the tape that holds it using wire cutters for electronics. Bend the resistor leads and insert them into the marked holes. Solder and trim the excess leads using the wire cutters. - Solder the Inductor (L1):
The cylinder shaped inductor must lie flat on the circuit board, but the legs of the inductor protrude from the end of the cylinder shape. This means that the leads of the inductor must be bent down 90 degrees each before soldering. Use a small pair of needle nose pliers to bend the leads. - Solder the YX8115 Integrated Circuit (U1):
The TO-92 package that the YX8115 IC is housed in has a flat surface and curved back. This shape is found marked on the top of the circuit board. In addition, the shape is marked U1. Insert the leads or legs of the YX8115 into the three holes where marked on the board. Make sure that this part is oriented the correct way around. - Install the Switch (S1):
Push the button cap onto the top of the switch. The switch is a component that must lie on its side, but has legs or leads protruding from the bottom. As with the inductor, the switch leads must be bent 90 degrees before soldering. Use small needle nose or similar pliers to bend the leads 90 degrees. Bend only one set of three leads, and leave the others straight. - Add the LED (D1:)
Insert with the long leg (anode) through the hole marked “+”. Make sure the flat side of the LED aligns with the PCB symbol. The LED must lie on its side, so the pins or leads of the LED must be bent 90 degrees before soldering. This is done by bending the leads down against the LED body so that it fits properly in the plastic case. - Solder the Battery Spring Terminals:
A helping hands magnifier, or similar clamping tool, is essential when soldering the battery spring terminals to the electronic flashlight kit board (see the image below). This is because each spring must be held in place flat on the board. Never hold the spring by hand when doing this soldering job, as the spring heats up quickly and will burn fingers. Refer to the above image for the position of the battery spring terminals. - Insert the Battery and Test:
Be sure to insert the battery the correct way around. Observer the (+) and (-) markings on the circuit board. Push the switch to toggle it on. Push it again to toggle it off. - Assemble the Electronic Flashlight Kit:
Place the completed electronic flashlight kit circuit board into the deeper half of the plastic enclosure. Insert the battery if it is not already present. Push the top half of the plastic enclosure onto the bottom half. The kit is now complete.
This is a classic DIY soldering project that emphasizes component orientation and soldering technique without overwhelming the learner.
Tips for Soldering Practice Kit Success
To get the best results from this soldering practice kit, keep the following in mind:
- Use a fine-tipped, temperature-controlled soldering iron (300–350°C is ideal).
- Tin the tip before soldering and clean it regularly with a damp sponge.
- Insert components flat against the PCB and bend leads slightly to hold them before soldering.
- Don’t overheat the pads — apply heat for 1–2 seconds then feed solder into the joint.
- Trim leads only after soldering.
Practicing good technique now will help when you move on to more complex DIY soldering projects.
Frequently Asked Questions About Soldering Practice Kit
Can I damage the kit if I solder incorrectly?
Overheating pads or reversing the LED polarity are common beginner mistakes that could damage the kit.
Will I learn anything useful from this small project?
Absolutely. You’ll gain confidence in soldering, learn to read PCB markings, and understand component polarity — all essential for future electronics work.
Conclusion
A soldering practice kit like this flashlight project is one of the most effective ways to begin learning electronics. It’s compact, affordable, and highly educational. Whether you’re an adult seeking a productive hobby or a student starting out, this simple electronic project for beginners is an excellent first step into the world of DIY soldering projects.