20 Pounds And A Gut Feeling Yields A Configurable Rubidium Atomic Clock Source

April 22, 2013 by Mike Szczys 62 Comments

So you see an image like this and the description “Aircraft stable oscillator” on an eBay listing for twenty pounds (about thirty bucks), what do you do? If you’re [Alecjw] you buy the thing and crack it open to find an atomic clock source inside. But he really went the distance with this one and figured out how to reconfigure the source from the way it was set up in the factory.

First off, the fact that it’s made for the aerospace industry means that the craftsmanship on it is simply fantastic. The enclosure is machined aluminum and all of the components are glued or otherwise attached to the boards to help them stand up to the high-vibrations often experienced on a plane. After quite a bit of disassembly [Alec] gets down to a black box which is labeled “Rubidium Frequency Standard”… jackpot! He had been hoping for a 10 MHz signal to use with his test equipment but when he hooked it up the source was putting out 800 kHz. With a bit more investigation he figured out how to reconfigure the support electronics to get that 10 Mhz source. We think you’re going to love reading about how he used a test crystal during the reconfiguration step.

Once he knew what he had he returned to the eBay seller and cleared out the rest of his stock.

[Thanks DIY DSP]

Atomic Skull Clock Reminds Us We’re Dying

March 26, 2013 by Ryan Fitzpatrick 25 Comments

Whether you like it or not, every second that passes brings you one step closer to your own demise. It’s not a comforting topic to dwell upon, but it’s reality. This art installation entitled ‘Memento Mori’ is a haunting reminder of just that. Even with all the advanced technology we have today, we still have absolutely no way of knowing just when our time will come.

[Martin] cast a real human skull, then added a 4 digit LED display that’s attached to a rubidium atomic clock (running a FE-5680A frequency standard). The display counts down a single second over and over, measured in millisecond-steps, from 1.000 to 0.001. He built a custom electronic circuit to convert the 10 MHz sine wave into a 1 kHz pulse signal, and used ATmega8 chips running an Arduino sketch to do the rest of the dirty work.

Watching the video after the break, with that smooth mysterious music in the background, one can’t help but ponder our mortality. On a personal note, this totally feels like something you’d find in a video game.

[Thanks Martin]

Continue reading “Atomic Skull Clock Reminds Us We’re Dying” →

Designing And Building A Wooden Mechanical Clock

March 19, 2013 by Jeremy Cook 16 Comments

Electronics are undoubtedly the basis for our modern society. Leaving out transistor-based devices, and a mechanical clock would be one of the most intricate devices man has come up with. As a Mechanical Engineer, I thought it would be a fun challenge to design and build my own gear-driven clock.

Because clocks have obviously been invented, I wouldn’t be starting from scratch, and I don’t think I could have figured out an escapement on my own. I explain my initial clock escapement and gear reduction design thoughts in this post, and originally getting the escapement to work was my biggest fear.

As seen in the first video after the break, the escapement gear is still a big problem, but not really for the reason I expected. The shaft that the gear sits on seems to be bent, so it allows the escapement to “go free” for part of it’s cycle, losing any sense of accurate timekeeping. Be sure to also check out the second video, especially around 1:50 when I show what happens when an escapement gear goes much faster than a normal clock. Continue reading “Designing And Building A Wooden Mechanical Clock” →

A Clock That Uses Sixty RGB Pixels

March 13, 2013 by Mike Szczys 11 Comments

Here’s a project inspired by a highly polished art piece. [Tobias] has been working on his own RGB LED clock which uses one light for each minute in an hour. He was inspired to start the project after seeing the Equinox clock. That one used a little PCB for each LED, and included an acrylic bezel and diffusers for each light. With the advent of LED pixel strings assembling one of these for yourself has become quite a bit easier.

The key part of the project is the laser-cut plywood frame which has a finger between each digit in order to perfectly space the lights. Each pixel is hot glued in place, with the Arduino board which drives them at the center of the frame. These lights are super bright, so [Tobias] also included a light dependent resistor which allows the system to measure ambient light and modulate the pixel brightness accordingly.

There are four parts to his project post so make sure you take some time to click around in order to get all the gritty details.

VFD Tube Clock Built Using Protoboard And Free-formed PSU

March 2, 2013 by Mike Szczys 8 Comments

[James Glanville] wrote in to show of his latest tube project. It’s a clock using six IV-3 VFD tubes. In addition to the tube displays the project prominently features a blue 3D printed case which hides away all the guts of the build including the Stellaris Launchpad which drives the clock.

Speaking of guts, you’ll want to look through a few of [James’] other posts on the project. His first write-up on this clock shows off the protoboard and point-to-point soldering that makes the tubes work. To help simplify things he went with a MAX6921 VFD driver chip. He mounted it dead-bug style on its own piece of protoboard and then soldered all of the necessary connections to the larger hunk hosting the tubes. There’s also an interesting post that details the switch mode power supply which ramps the USB 5V power all the way up to the 50V used to drive the displays.

If you like this you should check out the first VFD clock he built. We featured it a while back in a links post.

LCD-based QR Clock

February 28, 2013 by Mike Szczys 11 Comments

Here’s a new take on the QR clock concept that uses an LCD display. The concept comes from the work [ch00f] put into his two versions of a QR clock (both of which used LED arrays). The time of day is encoded using the Quick Response Code standard. This version generates a new code each second which encapsulates date, hour, minute, and second information. If you look at the image on the left you’ll notice the code is not centered. Take a look at the video after the break and you’ll see that’s because it’s bouncing around the LCD like a screensaver. Watch a little longer and you’ll see the psychedelic effects shown in the image on the right.

A PIC32 is driving the display. It’s connected to a DCF77 radio module which feeds the system atomic clock data. The color plasma effects are used to show when the device has locked onto the radio signal.

Continue reading “LCD-based QR Clock” →

Solar Clock Uses Capacitors For Style And Function

February 19, 2013 by Mike Szczys 16 Comments

This solar clock was built using a lot of salvaged parts. We find it interesting that [Nereus] combined a ring of storage capacitors with a power cell (translated) to create a hybrid energy storage setup.

The machine translation makes it a bit rough to understand how this works, but the schematic helps quite a bit. The pair of solar cells, which were pulled from some cheap solar cellphone chargers, feed the bank of capacitors encircling the clock face. If placed in a room that gets plenty of sunlight the cells will top off the capacitors which then feed an ICL7663 regulator. We’d love to hear comments on this part choice, as it’s our experience that linear regulators are rather inefficient. But anyway, the regulated power feeds both the energy cell as well as the clock motor. When output from the regulator dips the battery picks up the slack. The project also includes a voltometer and thermometer which can be displayed on the tiny LCD screen just about the six o’clock tick mark.

Now if you want something completely battery-free you’ll have to check out [Jack Buffington’s] take on solar clock.

[Thanks Manekinen]