These step-by-step instructions will guide you through making the Binary Thermometer available at applemountain.etsy.com.
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Step 1: Resistance Is Not Futile!
First find the four resistors taped together. These go in the rectangles marked on the board as R1, R2, R3 and R4. Bend the leads as shown in the above pictures and slide them in. You might want to spread the leads on the back so they stay in place while you solder. Solder the leads and trim them. It is should like the last picture when you are finished.
Step 2: The Lone Resistor
There is one lonely resistor that should be placed in the rectangle labeled R5. Solder it just like the other four resistors in the last step. It has a different value so don't mix it with the other four. It is a loner.
Step 3: Lights!
Next we will put the eight LED's onto the board. As you can see in the pictures, each LED has a flat side. The flat side on the LED should match the flat side on the white outlines printed on the board. Once the LED's are in place, check again to make sure they are oriented correctly before you solder them.
Step 4: Power!
Next you'll need to solder on the USB connector. The leads are small, but you only have to solder the two outer ones. Be sure to not bridge any of the leads with stray solder. You should also solder the USB connector tabs on the top and bottom of the board for a good mechanical connection.
If you want, you can power the board with an external 5v battery supply. To do this, leave off the USB connector and solder the battery leads into the GND and +5V holes on the board.
Step 5: The Brain!
Now you can place the microcontroller on the printed circuit board. The microcontroller will go on the rectangle outline in the middle of the board. As you can see in the first picture, one end on the rectangle has a notch. Also, notice in the second picture that the microcontroller has a dot on one end. Make sure the dot on the microcontroller and notch on printer circuit board are on the same side, just like the pictures shown. Now you can solder the microcontroller in.
The thermometer defaults to Fahrenheit. If you want to use Celsius, solder in the angled pin connector shown above the microcontroller in the above picture. It will read Fahrenheit until you slip the supplied pin jumper on the pins. If you want to go back to Fahrenheit, simply remove the jumper.
Step 6: The Temperature Sensor
This is the last component and be sure to solder it last. Make sure the flat side matches the flat of the outline on the board. Leave the leads long enough to provide room to bend it back towards to board if you need to later. Do not heat the leads anymore that you have to for soldering. It is sensitive to excess heat.
Step 7: Done!
Congratulations on a successful assembly! Plug into a usb power source and have fun!
Reading is as easy as simple addition. The left column of lights represents the tens and the right column the ones. The value for each lead, starting at the bottom is 1, 2, 4 and 8. So the temperature in the picture above is 1+2+4=7 for the tens and 1+2+4=7 for the ones making the reading 77 degrees.
Thanks for reading!
See more kits at applemountain.etsy.com