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Build Instructions, Page 3 / 6

Step 4: Crystal and Crystal Capacitors

Put the crystal into the area marked X1. It can go either way. Bend the legs a little, and flip the board over.

Bend pins to hold it in placeLocation of X1 crystal

Solder the two connections and use the diagonal cutters to trim the legs. Don’t leave too much wire behind, but don’t cut into the solder blob.

Solder connectionsTrim the legs

Next, add the crystal capacitors, C8 and C9. These can go in either way as well. Flip the board over, solder their connections, and trim the leads.

Measure resistance at test pointsAdd crystal capacitors

Before proceeding onto the next step, check the resistance between the power and ground again using a multimeter set to measure resistance. The value should be in the megaohm range, or an error because the resistance is too large. If there is a low value, there is a short in your solder joints–double check them!

Step 5: Reset Button

Next, insert the reset button SW1 into the printed circuit board. It can be tricky to fit in, so feel free to use a pliers to flatten the leads like the bottom buttons in the picture below.

Bend pins to hold it in placeLocation of X1 crystal

We want the plastic base to be pressed right up against the printed circuit board. Solder the four connection points.

Step 6: The first resistor

Take the 10k resistor, labeled with brown-black-orange, and bend one of the legs all the way back towards the other end. Insert it into the board where it is marked R5. The white circle indicates the body of the resistor should be on that side, and the top lead should go into the other hole. Solder the two connections, and trim the legs.

Insert resistor R5 where markedBend the resistor