Learn to Solder Kit - Flashing LED

This is the printed circuit board for the flashing LED kit. Please take note of the labels as shown. These will be where the components will be soldered onto. Note that there are labels for "+" which indicates that the component has polarity. For example where it notes "D1", "D2", etc. These stand for diodes, which acts as a one-way switch for current. Such as light-emitting diodes, or LEDs for short. Proper LED connection polarity is crucial for their correct operation. LEDs are electrically polarized components, meaning they require specific alignment to function properly. It is very important to connect the positive terminal (the longer leg of the LED), also known as the anode, to the positive supply. Likewise, the negative terminal, also known as the cathode, to the negative supply. Before we begin, take a look at NE555 and CD4017. These are DIP (Dual In-line Package) chips, also known as DIP integrated circuits or DIP ICs. They are electronic components that come in a rectangular package with two parallel rows of pins. These chips are widely used in various electronic devices and systems. Please take note of the little 'notch' markings; it's helpful to look for a notch (sometimes they can be a dot or sometimes both) on the IC package. These indicators serve as guides to find the first pin of the chip. This matters in our circuit here. Make sure you insert the chip in the right orientation.

First, go ahead and insert the LEDs as shown. They should fit where the holes are for labels D1 to D10. Make sure the longer leg is inserted into the holes where "+" is labelled next. Go ahead and solder the LEDs to the board. Here are some soldering tips to get you started:

• Prepare your workspace: Set up a clean and well-lit area for soldering. Make sure you have all the necessary tools and materials within reach.
• Safety first: Wear safety glasses to protect your eyes from soldering debris and heat. Additionally, work in a well-ventilated area or use a fume extractor to avoid inhaling soldering fumes.
• Heat control: Allow your soldering iron to reach the appropriate temperature before starting. Adjust the temperature based on the size of the components you're soldering to prevent overheating or damage.
• Cleanliness is key: Keep your soldering iron tip clean and tinned. Use a damp sponge or brass tip cleaner to remove any oxidation or debris. Apply a small amount of solder to the tip (tinning) before and after each use to maintain its effectiveness.
• Component positioning: Ensure that the components are correctly aligned and inserted into the PCB before soldering. Double-check their orientation and alignment against the PCB markings or the assembly guide.
• Heat transfer: Apply the heated soldering iron tip to the component lead and pad simultaneously. This allows efficient heat transfer and ensures a good solder joint.
• Avoid excessive heat: Minimize the time the soldering iron is in contact with the component to prevent overheating. Prolonged heat exposure can damage sensitive components and surrounding PCB traces.
• Soldering technique: Hold the soldering iron like a pen, and use your dominant hand to control the iron while your other hand feeds the solder. Touch the solder to the junction of the component lead and pad, not the iron itself, allowing it to flow and create a reliable connection.
• Quality over quantity: Aim for a neat and concise solder joint. Excessive solder can cause short circuits or poor connections. Remember, a small bead of solder is often sufficient for a strong joint.
• Inspection and testing: Once the solder joints have cooled, visually inspect them for any bridges, cold joints (dull or grainy appearance), or other defects. Use a multimeter or continuity tester to verify the connections.

Insert the NE555 chip into the DIP socket. DIP sockets offer a dependable and user-friendly solution for connecting DIP chips to a PCB. Their design ensures a reliable and convenient method for effortless installation, removal, and replacement of chips whenever necessary. Insert the DIP socket with the NE555 into the PCB, and solder it onto the board.

Likewise, insert the CD4017 IC chip into its DIP socket. Then insert the DIP socket into the PCB and solder it on.

The kit comes with 10 x 1K resistors, these are to be connected on the board where it is labelled R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10. Solder them as such on the PCB. It also includes 2 x 2.2K resistors. Connect these to R11 and R12 on the board and solder them on.

Insert the capacitors into the PCB as shown. Please note that these components have polarity, so insert the longer leg into the hole next to the marking denoting "+".

Next, solder the terminal block to the printed circuit board.

Insert and solder the trimpot resistor onto the PCB. Power up the board by connecting your power source supply such a coin cell pack to the terminal block!