Propeller clocks are nothing new to anyone who has been into electronics for a while. They use an idea called POV, Persistence Of Vision, which means that if something appears in the same spot consistently, at least 50-60 times per second, our brains think that it’s permanently there when it really is not. TV’s and Monitors use this method of display, so it’s not as uncommon as you might think.
After having seen so many propeller clock POV videos on Youtube, but no real description of how they work or how to build your own, I set out to make one and document how it was built. The Pyro Propeller Clock POV design criteria was short and sweet: be as simple as possible in order to encourage others to make their own, DIY style.
Pyro Propeller Clock POV – [Link]
After staring at the Union Square clock about 100 times, I decided to replicate it at home, so that I can watch the digits scroll by on my desktop. I named the clock after one of my favorite quotes from the video game Call of Duty: Black Ops, where the protagonist is politely asked for the meaning of a certain set of numbers which are being displayed on Nixie tubes. I feel it fits the piece, as even some native New Yorkers mistakenly believe that the display is the debt clock or something (that’s over in Midtown).
As a review, the clock is read like so: hh:mm:ss:msm:ss:mm:hh, which means that the time is read normally at first (military time), then it goes into milliseconds, then backwards milliseconds, then seconds, minutes and hours until midnight, in that order. Int he example picture, it is 19:30 with 9 seconds and 9 tenths of a second, the middle is usually a blur (set to hundredth of a second), then its 4 hours, 29 minutes, 50 seconds and 9 tenths of a second until midnight.
Fifteen-Digit Nixie Clock – [Link]
This prototype clock from UK designers James Auger and Jimmy Loizeau is powered by a microbial fuel cell. It features a conveyor belt of flypaper that attracts flies and drops their bodies into the fuel cell. Depending on the available fly supply, the process can generate enough power to sustain itself and power a digital clock, as well. [via]
A Clock That Eats Flies – [Link]
Writing a code for an analoge clock may seem a bit of a daunting task. Especially the calculations for the positions of the hands, but it isn’t really that hard at all.
In this instructable I will talk a little bit about the theory and then we’ll move on to the actual code itself. This was just a project build on the breadboard, while building my wifi radio. It started life as the script for a grafical volume button and ended up as a clock that never made it in the final project but it might come in handy for one of you out there.
Analog clock for graphic LCD – [Link]
I have been busying myself recently with some experiments into programming the Arduino prototyping platform.
I have already created some hardware, a Maxim DS1307 Real Time Clock shield and a Serially Interfaced, 8 digit 7 Segment Display based on a MAX7221 IC. So far I have created test routines to test my hardware but I wanted to really get my teeth into creating some more practical code.
And here it is, A more or less functioning LED clock.
Arduino Cloc: A Maxim DS1307/MAX7221 Based Clock – [Link]
In honor of the new chronodot, we’ve put the brains behind the chip (The maxim DS3231) into our partfinder! This is a high precision ‘big brother’ to the DS1307. It has a built in temperature compensated oscillator so that its very precise. They are a bit chunky but good when you want to really keep track of time and cant integrate a GPS module.
DS3231 – High precision real time clock with built in oscillator – [Link]
I really like nixie and numitron clocks, but I never worked with them before. So I decided to give it a go. I choose numitrons because of 2 reasons: first of all nixies need a higher voltage than numitrons to work. Nixies need around 170V DC and numitrons only 4,5V so they are safer to work with and don’t need a special powersupply.
Numitron clock & thermometer – [Link]
Bob Alexander wrote in with his elegant USB clock/web data display: [via]
When I built my Homemade Digital Clock, I shamelessly overdesigned it. It had an eight character alphanumeric display (plus two discrete LEDs for a colon), four more discrete LEDs for indicators, two printed circuit boards, and two microcontrollers (three, if you count the GPS it uses as its time source), one of which was running at 20MHz. That’s more processing power than the Apollo spacecraft had on board! All for a stupid clock!
LED Display Shows Time and RSS Feeds – [Link]