Section 2 - The Deployment Side - Eggtimer Rocketry Eggtimer TRS Assembly Manual

Section 2 – The Deployment Side
Next you will be soldering the SMT components that make up the deployment side of the
board. They are to the right of the GPS module. In general, you will be working from the GPS
module outwards towards the edge of the board.
__ Locate the space for the two MOCD217M2 optoisolators, they are just below the GPS
module. They are a SOIC-8 package, 8 pins with "J" leads.
On the UPPER optoisolator's spot, flow a little solder on the bottom-right pad, just
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enough to cover the pad.
__ Remove ONE of the MOCD217M2 optoisolators from its carrier. With tweezers,
gently place it onto the upper pads. If there is a notch on the optoisolator, it should be facing
up. If not, the writing should be going from top to bottom (i.e. readable from the left side of
the board).
__ With the other hand, gently touch the soldering iron to the lead on the pad that you
tinned earlier, until the solder melts and flows around the lead. Hold the iron for another 5
seconds to allow the solder to wick under the lead. Remove the iron and hold the optoisolator
in place for at least 5 seconds to allow the solder to cool.
With a 10x jeweler's loupe, inspect the leads to make sure that they are all centered on
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the pads. If they are not, get out the tweezers, heat up the solder joint, and gently move it into
place.
__ Once you are satisfied with the alignment, carefully solder the remaining pads, skipping
pads and alternating sides to help prevent solder bridges and to prevent overheating the part.
Wait at least 10 seconds between each solder joint to allow the part to cool.
Inspect all of the solder joints with a 10x jeweler's loupe, and redress them as
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necessary.