clock hacks

977 Articles

Logic Clock Without An On-board Oscillator

April 7, 2010 by 58 Comments

[Lucassiglo21] developed this logic clock without using a crystal oscillator or a resonator. Instead, he’s letting the incoming electricity keep the time for him. The supply is AC at 50 Hz so he’s using some 4017 decade dividers to reduce that down to a 1 Hz signal. From there it keeps track of the ticks just like the last digital logic clock we saw.

If you’ve used AC line frequency as the clock source in your project we’d like to hear about it. Send us a tip and make sure your writeup includes a schematic. We’re especially interested to see if anyone has a good way of using this method with inexpensive microcontrollers.

Clock Sans-microcontroller

April 3, 2010 by 20 Comments

This clock requires no microcontroller. It’s actually a digital logic counter that functions as a timepiece. [BlackCow] used six decade counters to track seconds, minutes, and hours. The output is displayed on four 7-segment digits using BCD-7-segment decoders that you can learn about in our binary encoded decimal post. The actual timekeeping is done by a quartz clock circuit he pulled from a Mickey Mouse clock. This would be a perfect circuit to build in a digital logic simulator, just follow the schematic and learn as you go.

POV Clock Inside Acrylic Block

March 20, 2010 by 25 Comments

This gorgeous persistence of vision clock was built a couple years back by [mb1988]. The housing is made of acrylic with a hard drive motor mounted in the center of the back panel to spin a PCB. The two-sided circuit board is home-made and includes a battery for power, ATmega32 for the brain, 32 LEDs, four display drivers, and a real time clock module. The spinning hard drive motor is nearly silent and already has threaded mounting holes on it. [mb1988] uses an optoelectric sensor to sync the display with the rate of rotation. The forum post includes download for the code and hardware details. Don’t miss the demonstration after the break.

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Pure TTL Based Clock

March 16, 2010 by 28 Comments

We’ll just say, [Kenneth] really likes clocks. His most recent is a pure 7400 series TTL based one, ie no microcontroller as seen in the past, here, here, and here. The signal starts out as a typical 32,768 crystal divided down to the necessary 1Hz, which is then divided again appropriately to provide hours and minutes.

As far as TTL clocks go, this is nothing too original; until it comes to his creative button interface. By using a not as sexy as it sounds multivibrator, he can produce a clean square wave instead of the figity signals produced from buttons to advance and set the time. Like always, he also provides us with a thorough breakdown of his clock, after the jump. Continue reading “Pure TTL Based Clock” →

Tube Clock Database

March 9, 2010 by 16 Comments

[youtube=http://www.youtube.com/watch?v=75Yl9hyPFRE]

[Brian] wrote in to show us a site he’s been working on for a while. He’s been building a tube clock database. We didn’t realize there was actually a big enough draw for such a site, but we have to admit that we spent more than a few minutes browsing through the different clocks. There isn’t a ton of data for each clock, but there are links to individual project pages wherever available. There is also a growing amount of information on the different components themselves, so submit any data you have that he’s missing to help flesh it out.

The video above wasn’t chosen for any reason other than it is quite stylish.

Space Invaders Clock 6 Years Ahead Of Pong Clock

March 5, 2010 by 10 Comments

Space Invaders came out in 1978, six years after Pong. That means this Space Invaders clock uses newer technology, right? Nope, it’s the same hardware as the Adafruit Pong Clock with some updated firmware. Still, as you can see after the break, the effect is pretty nice. Pong was cool, but having a clock that scrolls through several classic games would be cooler.

[Dataman], the guy responsible for this firmware hack shared his code. It should be easy enough to alter it for any clock using a KS0108 graphic LCD screen. So what’s next? Can someone pull off a black and white Ms. Pac-Man that looks decent on the 128×64 display?

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