Tiny hardware-based DSLR intervalometer

diy_dslr_intervalometer

Most DSLR cameras have the ability to take pictures at set intervals, but sometimes the menu system can be clunky, and the options are often less than ideal. [Achim] is a big fan of time lapse photography and has been hard at work creating a hardware-based intervalometer to suit his needs. He has just finished the second revision of the controller which is just about small enough to fit inside the housing of a 2.5mm stereo plug. The timer is not 100% universal, but so far he has confirmed it works on Nikon, Canon, and Pentax cameras.

Based on a PIC10F222, the circuit’s operation is quite simple. Once the dongle is connected to your camera, you simply need to take two pictures anywhere from 0.4 seconds to 18 minutes apart. The intervalometer “watches” to see how long you waited between pictures, and proceeds to take shots at that interval until the battery dies or your memory card fills up.

As you can see in the video on his site, the timer works a treat. If you want to make one of your own, swing by his site to grab schematics and code – it’s all available for free.

*Whoops, it looks like we’ve actually covered this before. Our apologies.

You can keep your mints safe; we have the technology

After having his mints disappear for quite some time [Quinn Dunki] came up with an idea to get back a the fresh-breath thieves. A bit of circuit design, parts scavenging, and free-form construction led to the creation of his mint-tin burglar system.

Here’s how it works. Flip the on/off switch in the base of the mint tin before you head off for lunch or a coffee break. When the foul-mouthed pilferer hits up your stash they’ll get what they were looking for at first. But by opening the tin they tripped a timer circuit that will send the mints vibrating across the table soon after having been opened.

The breadboard above holds the prototype timer circuit, built around or friend the 555 timer. The vibration motor from a cellphone is a perfect choice for this hack as it’s very small and is just waiting to run from a low-voltage source. We especially liked the use of the cells from inside a 9V battery as a power source and the compact assembly that manages to fit inside the mint container.

Another Smarter Water Heater Timer

When notes stuck to the water heater failed [Ryan] decided to whip up “the world’s most expensive 240V relay” using a servo, a real time clock and of course an Arduino. All in an attempt to save a buck or two thanks to LA’s “Time-of-Use program”.

Using a protoshield Ryan soldered up a RTC module using the DS1307 chip. On board he added some LED’s and switches including a holiday switch keep the heater off, a next cycle button when you need some hot water and to hell with the expense, and a pulsing blue LED.. for no reason at all. The board flips the mechanical switch using a servo and piano wire, simple but effective. We wonder how many days/weeks it will take for it to offset its expense?

Keep Fun in Check With a Parental Count Down Timer

Gaming industry software engineer [Pedantite] writes in to let us know about his latest endeavor, an AVR based parental assistant timer: Good Times.   Looking for a new project that would be both useful and interesting, his wife suggested a “time out/ time’s up timer”. Like most of us [Pedantite]‘s children are well studied in the arts of procrastination and mischief.  In the kids’ case this leads to time outs and break time running amok. The solution, in this case, is pretty much an advanced DIY egg timer with fun sounds.

The timer sports all of your basic countdown-timer functions including a 4 digit 7-segment LED output display, stop light style LED indicators, and controls to start/pause and stop the count down. The count down time can be input via the +5 minute, +1 minute, and +15 second buttons. There is even a happy/sad button to toggle between “time out” and “break time” modes. Two Atmel micros power the device, an AT Tiny 2313V for the capacitive touch keypad and an AT Mega 644P for the display, audio, and time measurement.  There are a lot of excellent techniques used in the build, some which we have covered here:  Four 595 Shift registers for the display; A 4 bit r2r DAC for audio output.

[Pedantite] is still in the process of writing up the project in multiple posts, and would love to know what you all want to hear about. Check out his blog for details and a quick video of the timer in action! Also, if you are interested in capacitive buttons, check out part 2 of the writeup.

Wireless luge timer levels the playing field

wireless_luge_timer

In Colorado, amateur luge competitions are serious business.

Every winter, [Ryan's] friends dig a long luge track through the many feet of snow that occupies their yard, and have competitive sled races to see who can make it down the giant hill in the least time. They call it the Mario Cup, after one of the participants, not the Nintendo mascot, and they were in desperate need of some timing equipment.

You see, the luge track is several hundred feet long, and they decided that a human armed with a stopwatch is not a good enough means of picking a conclusive winner. A set of three Arduino sensors packed inside plastic food containers were used along with light sensors to track when the luger passed the start, midpoint, and finish lines of the race. XBee radios then transmitted the timing data back to the base station for recording.

The system worked quite well according to the participants, and they look forward to using the system again in the future. Of course, improvements have been planned, including dual timers at each checkpoint to gauge the luger’s speed, as well as a Christmas-tree starting signal like you see at drag races.

Continue reading to see a video below of the luger’s in action, as well as the timer system undergoing some tests.

[via Make]

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Birthday gift is a constant reminder of impending AARP membership

birthday_countdown_timer

Sometimes milestone birthdays can be a bit depressing. 30 is rough, and 40 tougher – but 50…that’s a big one!

[Ryan’s] uncle is going to be turning 50 shortly, and in the interest of good-natured fun, he has constructed a handy birthday countdown timer for his uncle, lest he forget (or tries to avoid) the big day.

The device displays the amount of time left before his uncle’s birthday, playing an audio clip of “Don’t fear the Reaper” when the clock strikes 00:00. This is accomplished by using the MSP430′s internal clock to keep time, while also interfacing with a Nokia 3310 LCD panel to display the countdown timer. The music is provided by the circuit board from a greeting card he gutted for the project, which was wired to the LaunchPad in order to be triggered at the right moment. Everything was crammed inside an Altoids tin, as you can see in the picture above.

Though not overly complicated, it’s a fun little project, and we’re hoping his uncle gets a big kick out of it. Once his birthday has come and gone, [Ryan] plans on converting the piece into a permanent desktop clock for his uncle.

Keypad input scanning by a 555 timer

[R-B] designed a 555 timer circuit to scan a keypad. Keypads are common interfaces for small projects and require row and column scanning by a microcontroller. [R-B's] setup allows you to reduce the number of pins used on the microcontroller to just two. One is an interrupt that is triggered when any of the buttons are pushed, the other reads the frequency from the 555 chip. Each button has its own resistance which alters the frequency of the 555. The microcontroller reads the frequency for 100ms using a timer. The number of timer overflows that occur during that period directly correspond to the button press (five overflows for the numeral 5, zero overflows for the numeral zero).

We usually debounce our button presses for 40 ms, this is more than twice that amount of time but still not a staggering difference. It does make us wonder if you will miss quick button presses? The only really way to know is to try this out yourself. Check out the video after the break and don’t forget to leave a comment with your own experiences in working with the circuit.

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