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3. Speaker, transistor, LEDs galore

Following the resistors in the previous part, this one adds more components to the board such as the speaker, transistor, and some LEDs. For this part, you will need the speaker, PN2222A transistor, red and green LEDs, and the power switch.

Insert the power switch into S7. Apply tape to it, and flip the board over.

Ensure the switch is flush with the board after flipping. Using your soldering iron, solder the pads of the switch. Then, flip your board over.

Insert the transistor Q1. The flat side of it should be facing the edge closest to the right hand side of the board. This is a PN2222A transistor, which will be used to boost the volume on the speaker.

Gently bend the leads of the transistor to keep it in place when flipping the board. Then, flip the board.

Ensure the transistor is flush with the board after flipping. Using your soldering iron, apply solder to the pads of the transistor. Then, cut the leads with diagonal cutters. Flip the board when complete.

Insert the speaker into SP1. Gently bend the leads to keep it in place when flipping. Then, flip the board.

Ensure the speaker is flush with the board after flipping. Using your soldering iron, apply solder to the pads of the speaker. Then, cut the leads with diagonal cutters. Flip the board when complete.

Obtain the two 5mm red LEDs. The red LEDs will be inserted into LED9 and LED7. The shorter lead goes in to the hole that is closest to the flat indication on the circuit board. You can also feel on the LED, there is a small flat edge on the side that corresponds to the flat indication on the circuit board. See the photo as an example.

Insert the other red LED into LED7.

Here are the two red LEDs in their proper positions, and in the proper orientation. Gently bend the leads to keep them in place when flipping the board. Then, flip the board.

Ensure the LEDs are flush with the board after flipping. Using your soldering iron, apply solder to the pads of the LEDs. Then, cut the leads with diagonal cutters. Flip the board when complete.

Time for the green LEDs now! Obtain the two 5mm green LEDs. The green LEDs will be inserted into LED8 and LED10. The shorter lead goes in to the hole that is closest to the flat indication on the circuit board. You can also feel on the LED, there is a small flat edge on the side that corresponds to the flat indication on the circuit board. See the photo as an example.

Insert the other green LED into LED8.

Here are the two green LEDs in their proper positions, and in the proper orientation. Gently bend the leads to keep them in place when flipping the board. Then, flip the board.

Ensure the LEDs are flush with the board after flipping. Using your soldering iron, apply solder to the pads of the LEDs. Then, cut the leads with diagonal cutters. Flip the board when complete.
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Page last updated on: Sat Jan 18 20:17:26 2020