Pure TTL Based Clock

March 16, 2010 by Jakob Griffith 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” →

Binary Clock Uses DS3232 RTC

February 17, 2010 by Mike Szczys 24 Comments

[Kenneth Finnegan] quenches our clock-a-day compulsion with his Arduino based binary timepiece. The clock uses a 5×7 LED matrix as a display and shows month, day, and time. He sourced a DS3232 real-time clock which automatically compensates for temperature to achieve very accurate time keeping. We like the super-cap circuit he added to keep the RTC running if the power is cut.

Is an Arduino overkill here? Well, the code is certainly not filling the 16k available on the ATmega168. At $4.32, the $1-2 you could save by using a lower-grade chip is not worth having to rewrite the code developed during prototyping. [Kenneth] also mentions that these projects usually only hang around for a few weeks before they’re re-purposed for the next endeavor.

Take a look at [Kenneth’s] superb hardware walk through in the video after the break. If you’re a fan of clean breadboarding, he’s also made a time-lapse of the circuit building process.

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120v Switching

January 31, 2010 by Mike Szczys 52 Comments

[Kenneth] built a 5v controlled power outlet inside of a junction box. We’ve seen plenty of projects that can switch 120v outlets using 5v logic for refrigerator controllers, lighting controllers, or grow systems, but they almost always use solid state relays to facilitate the switching. This iteration uses mechanical relays along with the necessary protection circuitry. The project is housed in an extra deep single-gang box and allows for individual switching of the two outlets. You can see this connected to an Arduino switching two lamps after the break.

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Hackaday Links: Sunday January 24

January 24, 2010 by Jakob Griffith 16 Comments

Everyone Remembers Free day right? [The Ideanator’s] Bus Pirate came in such a nice red box – he decided to make it his permanent case.

[Chico] is in the middle of making a CNC, but decided to make some music with the steppers in the mean time.

What looks like an old wooden box is actually [Ludvig’s] super sweet retro arcade cabinet. Complete with a giant emergency stop red button.

Who says Legos are dead? [Carl] used them to create a simple and cheap diffraction grating projector. Including video!

[Torchris] used an Ethernet shield exactly as it was designed, sending data over Ethernet. Still a nice hack for those needing help working with Ethernet shields and Arduino.

Finally [Robert] let us know about a friends Arduino Binary Clock. But we think his elegant use of tape and a sand blaster to engrave glass is cooler.