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The LED Torch - Soldering the board

 
 

1 Preparation

Build It

  • Soldering the board together should be a fairly quick process, and so long as you have no issues, it shouldn't take more than an hour.
  • Firstly you'll need to make sure you have all the correct components.
  • You will need:
    1. 1 x 3V Cells
    2. 1 x 3Ω resistor
    3. 1 x Any resistor
    4. 1 x 3mm White LED
    5. 1 x 6mm PTM Switch
    6. 2 x 5cm lengths of single core wire (any colour)

Components.jpg

  • The board is clearly labelled, to show you where everything is placed.
  • This is the side where the components sit.

Build02.jpg

  • This is the side where you apply the solder

Build03.jpg

Build It

  • Place you resistors on the board as shown below.

Build04.jpg

  • Then pull the resistor up to the PCB and bend them slightly - DO NOT BEND THEM FLAT ON THE PCB.

Build05.jpg

  • Clamp your board into the bulldog-clip on your soldering iron stand, and make the legs of your resistors stand up as straight as possible.

Build05b.jpg

  • Then carefully solder each leg in place.
    1. Hold the tip of the iron so that it is touching both the solder pad and the leg of the component.
    2. Hold it there for the count of three.
    3. Feed in the solder so that it melts over the pad and leg.
    4. Withdraw the solder.
    5. Withdraw the iron.
    6. Use side cutters to trim off the legs.
  • Your solder joints should look like this.

Build06.jpg

  • Next we need to solder in the LED. Make sure you put it in your board the correct way around. The long leg goes through the hole marked with a +.

Build07.jpg

  • When you place the LED into the holes, bend it over so that the bottom of the LED touches the edge of the board.

Build08.jpg

  • You may want to use masking tape again, if you feel you need to. Solder the LED in place.

Build09.jpg

  • Next take your lengths of single-core wire and strip off the insulating plastic as shown below.

Build10.jpg

  • Now solder the wire into the board as shown.

Wireforbattery.jpgWiresoldered.jpg

  • Make sure the positive wire comes from the top of the board and the negative comes from the bottom.
  • Next, use a screw driver to coil the bare wire.

Twisting wire.jpg

  • Our last component is the PTM switch. Use masking tape to keep it in place.

Soldercomplete.jpg

  • Then solder it into the board.

Solderjoints.jpg

2 Assessment

Badge It

Silver - Progress ladder Yellow, Identify and solder simple components (e.g. resistors) to PCBs, with assistance.

Gold - Progress ladder Green, Solder more challenging components (e.g. ICs) to a PCB, with assistance.

Platinum - Progress ladder Blue, Confidently and consistently solder components to a high standard.

  • Once you have completed your board, take it to your teacher for testing.
  • If it works, take pictures of both the solder side and the component side.
  • You will be assessed on the quality of your soldering and component placement.