Colour also can display the time Build a LED colour clock

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1 Colour also can display the time Build a LED colour clock Not all clocks use digits to display the time. This neat little clock tells you the time by using different colours for each digit. The colours are based on the resistor colour code (sort of), so for most electronics DIYers it should be quite easy to read. The colour clock is a relatively easy project, although it does include some surface mount components, so you will need a fine tipped, temperature controlled soldering iron and good eyes (or a good magnifier lamp). Please read these instructions carefully before you start assembly! Note that the LED package square pad corresponds to the longest lead on the RGB LEDs. Components list R1-R3, R12: 120 ohm (121) R4-R5: 1M (105) R7: 1k R8-R11, R13-R14: 10k C1: 220uf C2: 104 chip capacitor C3: 10uf C4: 104 chip capacitor L1, L2: SMD LED L3-L8: 10mm RGB LEDs LR1: photoresistor Q1: 9012 U1 DS3231 real time clock U2: ASM1117 IC1: 15W413AS

2 Starting from the USB socket, solder the components in place, paying attention to orientation of the polarised components (the resistors and ceramic capacitors can go in either way around). Make sure there are no solder bridges between the pins of either IC and ensure the ICs are the right way around before soldering! As shown above, the two mercury switches tilt outward at an angle of 45. Be sure the two mercury switches are tilted outward or the tilt direction sensing function of the clock will not work. Next solder in the rest of the components on the bottom side of the PCB. After this is done, plug in power via the USB cable and press the two touch buttons to test whether the device is functioning. If you hear the beeper beep when you press the button, the clock is working normally.

3 Now fit the four PCB stand-offs using the short screws, as per the photo above. This lets you work on the clock without squashing the mercury switches down towards the PCB. Fit the SMD LEDs - the end with a green dot is negative and goes to the right-hand end of the PCB (with the writing on the PCB the correct way up for reading). Now fit the first RGB LED, dropping it in until the longest lead just touches the desktop, and, making sure it is in the right way around (longest lead goes in the hole with the square pad), solder the positive pin in place from the top. Then solder the rest of the pins, making sure it is vertical and at right angles with the PCB in both directions. The rest of the LEDs can be fitted in the same way. They should all come out the same height if you use the desktop to align them. Once done you should be able to test the clock. Check the buzzer, LEDs and touch buttons. If all is well you can proceed to the next step.

4 In order to protect the RGB LEDs from damage and to give the clock a more interesting look, six small vials or bottles are included in the kit. One vial is fitted over each LED and glued in place, but make sure everything is working correctly before you do this. You can use hot melt glue or another strong glue such as epoxy or 2-part acrylic, but don t use superglue as it will cloud the vials.

5 Make sure all vials are aligned nicely, you don t want a wonky clock! To finish the clock, turn it over and insert the backup battery (the + side of the battery faces outwards), then fit the bottom acrylic cover and fix in place with the four long screws. Thread a nut onto each screw about half way along the screw, then screw each screw into place several turns and then gently tighten the nut down onto the acrylic. This holds the cover in place and provides four adjustable feet for the clock. Make sure all four screws are protruding the same amount and that the clock sits flat on its feet. Make sure to remove the protective film from the acrylic.

6 Now power up the clock via the USB cable and you should see the colours start to change.

7 Setting and using the clock Tilt the clock forward as shown to set the time using the touch buttons. The Set button moves between digits, and the Add button adds one to the count with each press. You need to scroll through all six LEDs with the set button. Once the clock is set to the correct time, just press the set button one more time and the time will be set. When setting the alarm, the two SMD LEDs will light up to show the alarm is on. You can t set the alarm time unless the LEDs are lit. To turn the alarm off, tilt the clock back (the opposite direction to when setting the time) and just press the Add button without first pressing the set button. The two LEDs should go out to tell you the alarm is off. Setting the alarm is a little quirky. Rotate the clock 180 degrees so that the USB connector is pointing towards you and then tilt the clock towards you. You are effectively tilting it back, but it makes it easier to set this way, and the clock is designed to transpose the LED positions during alarm setting, so that the seconds LEDs actually display the alarm hours setting and the minutes LEDs display the alarm minutes setting (but transposed). This seems odd, but works well in practice. You set the alarm in the same way as the time the set key switches between setting the hours and minutes while the add key increments by one. Note that you don t set the tens and units individually when setting the alarm time, you just scroll through 0-23 for the hours and 0-59 for the minutes. Once the alarm time is set, just press set again to finalise the alarm setting procedure. The two SMD LEDs should be lit to indicate that the alarm is on. When the alarm sounds, just touch either touch switch to turn it off. The clock also flashes the LEDs and beeps every half hour by default. If the beeping annoys you it can be turned off by tilting the clock forward as if you are going to set it. When the clock is in beeping mode, the left-hand SMD LED will light when you tilt the clock forward. Just press the Add button (without first pressing the set button) and the LED will go out and the clock will stop beeping. Note that this setting isn t saved, and so if you power the clock down, it will start beeping on the half-hour again when you power it back up. For a permanent solution just don t install the piezo sounder, although this will disable the alarm of course. The clock will also display temperature with it sitting upright just touch the Set or Add buttons and only the two middle RGB LEDs will light. We have found this to be not overly accurate, however.

8 Night effect. Colour table 0: White 1: Red 2: Orange 3: Yellow (greenish yellow) 4: Green 5: Greenish cyan 6: Blueish cyan 7: Dark blue 8: Purple 9: Pink/Magenta 2015 LEDsales ( Kit design by Kevin Wu.