Since banning tablets in the bedroom overnight, Miss10 has needed an alarm clock. So, for the last few months we’ve been looking for something suitably cool, and inexpensive.
As it happens, the Adafruit Ice Tube Clock Kit is exactly the right answer. Exactly the right amount of powder blue glow that is needed, matched with undeniable 80’s Russian retro chic.
We spent the past few nights building it, doing a bit of three handed soldering, and joint assembly.
As usual, things need to be modified to be truly personal, so we added some special touches that set her clock apart.
Using a 5ppm 32kHz crystal, rather than the provided 20ppm crystal, should keep accuracy within half a second per day (worst case) and only adds a few cents to the build.
Also, it is a bit inconvenient to reach around the back of the clock to read the date and activate the snooze function. So, we added an IR sensor to button 2 (the Set button) to enable these functions with just a hand wave.
A Pololu Sharp 10cm IR Distance Sensor is mounted directly on top of the 5V regulator for several reasons.
- To stay inside the short range null (<2cm) and reflections, the IR sensor needed to be at the front of the housing.
- To keep the Vacuum Florescent Display seemingly floating in the case, the IR sensor needed to be low profile.
- To prevent the sensor draining the standby battery, the IR sensor needed to be powered off the main power supply (before the isolation diode).
Using a few carefully bent mounting pins (provided with the IR sensor), it is fairly easy to solder the IR sensor directly onto the legs of the regulator, providing a neat mounting point. The sensor line, generating a low signal when triggered, is run around the end of the PCB and paralleled onto the Switch 2 active pin.
With the IR sensor in place, a hand wave is all it takes to trigger another 10 minutes snooze. Which, on second thought, is probably not such a good idea.
Very excellent! Once you activate the IR sensor a relay to a small transmitter could activate several receivers; one to start the coffee, one to open the window shade, and one to play music real loud in the next room – unless you get there to turn it off first.
Can you provide a source for the 5ppm 32kHz crystal?
See this link for Digikey Part 300-8763-ND
http://www.digikey.com.au/product-detail/en/CFS206-32.768KHZFB/300-8763-ND/2217074