Beefy Battery Backup Still Running After A Decade

October 8, 2010 by Mike Szczys 39 Comments

In 1997 [Michael Butkus Jr.] found an uninterruptible power supply in the dumpster. The batteries were shot, but he needed a backup to keep his pellet stove running for heat, drive the exhaust fan to keep the smoke out of the house, and power his computer and other electronics. After a bit of head scratching he decided to beef up the UPS using deep-cycle batteries.

He actually built two of these. One is smaller, and similar to what we’ve seen before. The other is larger and uses four batteries, two pairs in parallel which are then connected in series. He’s careful to use heavy gauge wiring and 50 amp fuses for each battery, both of which will protect against the risk of fire. One thing we found interesting is that the batteries are stored in the basement, directly below the UPS which is connected via a short run of 12 gauge home electrical wire.

We were happy to see that he’s done updates at the top of his post over the years. He lost a few batteries due to neglectfully letting the water levels drop too much. He did switch over to sealed automotive batteries sometime in 2004 or 2005. Looks like things have been going strong ever since.

[Thanks Spencer]

Wood Burning House Heater

October 4, 2010 by Mike Szczys 59 Comments

Dabbling in alternative heating technology, [Rob Steves] built a wood stove to dispose of his scrap wood while negating his home’s fire insurance at the same time. As the leftover bits from his wood projects started to stack up he wondered how he would dispose of them. Burning the bits for heat means he’s using every last bit of the lumber. The internal tank from an electric water heater was repurposed as a combustion chamber, with exhaust gases escaping through some high-temperature flexible tubing. The glass panes were removed from one of the fireplace doors to give the off-gases a place to go. The result is a rocket stove that burns very hot and does a great job of warming his house.

It’s not the safest way to heat a home, and there may be coding issues with your municipality. But this might go well in a remote location, like that cabin where you have to generate your own electricity.

[Thanks HybridBlue]

Gutting An Air Freshener For The Parts

September 24, 2010 by Mike Szczys 40 Comments

[Doug Paradis] took a good look inside the Air Wick Freshmatic Compact i-Motion and then stole all the parts for other projects. We’ve looked at adding a manual spray button or making air fresheners Internet enabled before. Those models didn’t have parts that were all that interesting, but this one has a passive infrared motion sensor. You’ll also gain three switches, a PNP transistor, and an LED.

Price seems to be all over the map for this model, but [Doug] says you can find it for $8 or less. After showing how to make a tool to bypass the triangular security screws, he explains how to access the PIR sensor. But if you want to be all you can be with the hardware, he details the modifications needed to patch into the analog and digital circuitry on the rest of the board too.

Low-power Wireless Home Automation Sensors

September 16, 2010 by Mike Szczys 41 Comments

The line between serious research and well-executed hacks has been getting pretty blurry lately. The device above could have been designed in your basement but it actually comes from researchers at the University of Washington. They are working on low-power home automation sensors for monitoring things like humidity, temperature, air quality, and light. The key point in their research has been the use of a home’s electrical system for wireless communication. Operating at 27 MHz has proven quite efficient to the point that one of these modules placed within 10-15 feet of an electrical run can communicate with the rest of the home, powered only by a watch battery projected to last ten years.

That’s kind of exciting, it’s a heck of a lot easier to produce and distribute a set of small boards like this than to run communication wiring throughout the house. Now we just need to pair this with the Air Force’s parasitic power work and there’ll be no need for a battery at all.

[Thanks Sidhant]

Automated Entry For A Garden Gate

September 14, 2010 by Mike Szczys 14 Comments

[Dan McGrath] tipped us off about a solution for a problem that most people don’t have. He built a web-based entry system for his garden gate. This isn’t quite as original as that chain and sprocket dorm room system, but it does use a keypad for entry. [Dan’s] already got a web server and home automation box that is always running. He coded a webpage that presents a virtual keypad for code entry. If the right code is input the system unlocks the electronic strike on the other side of this gate. Since the interface is a web page you can load if from any web browser (an iPhone is used for demonstration purposes after the break). But if you don’t have internet access you’re in trouble; there’s no physical keypad. But we guess you could always just jump the fence. Continue reading “Automated Entry For A Garden Gate” →

Keypad Door Lock, Better Than Last Years Keyfob?

September 11, 2010 by Jakob Griffith 13 Comments

It’s that time of the year again. The leaves are changing colors, it’s getting colder outside, and all the littler hackers are off to college. Which means we get to see an influx of dorm room locks and openers.

[Adam] is back at it again with a new keypad dorm room lock. Last year he had an exceptional setup using a car keyfob, so we’re a little curious as to why he would revert to such a low level system as a keypad that isn’t even color coded.

Perhaps its in his “new” way of presenting the hack. Rather than a blog or write up, he documents the entire most of the process in a little less than 20 YouTube videos. Watch him testing out the system after the jump.

Continue reading “Keypad Door Lock, Better Than Last Years Keyfob?” →

Web Controlled Watering Can

September 9, 2010 by Mike Szczys 9 Comments

Here’s a watering can and water vortex that are controlled with a webkit browser interface. The interface displays a drawing of the watering can on your browser. If you grab one of the handles on the circle around the image and move it, the can will rotate as well.

Okay, so this isn’t going to change the world and actually presents a fairly useless watering setup. But [Ben] seems to be a master of fabrication and that’s what we appreciate in this build. The watering can is solidly mounted and moves fluidly with seemingly little effort from the motor. He uses a spring to keep the rope loop taut, sourcing a castor wheel and automotive power-window motor to provide the motion. The hinged base on which the can sits has a potentiometer in it, used to measure the current position of the watering can. Remember these techniques as they’ll come in handy in your future builds.

There’s also a little bonus at the end of the video after the break. We wondered what [Ben] might use that power drill controller hack for. Looks like it makes an appearance in his water vortex work.

Continue reading “Web Controlled Watering Can” →