C-clamp Current Monitoring

December 21, 2009 by Mike Szczys 24 Comments

[Hydronic] did some tests to make his own current sensor using a c-clamp wrapped with wire. He tried several different cores including an aluminum carabiner, the C-clamp, and what he calls a u-lock (removable chain link). There is some success here that could be improved with cleaner winding and by adjusting readings based on the length of wire used in the wrapping.

This did make us perk up a bit right off the bat. Reader [Mure], who tipped us off about this, suggested that this could be used to make your own Kill-a-Watt without including it in the circuit. We made the jump to house monitoring. We’d love to have a data tracker for our home circuits to curb wasteful energy use. Perhaps we’ll try to make our own sensors and produce a diy Cent-a-Meter.

Hacking ZigBee Chips: CC2430

December 21, 2009 by Mike Szczys 2 Comments

[Travis Goodspeed] took an in-depth look at the debugging protocols for some ZigBee chips and posted his findings. In particular he’s looking at the CC2430 System-on-chip. These chips have a debugging protocol that is not hard to implement if you know what you’re doing. Certainly his tips make it easier for the rest of us. Don’t miss the info about reading from, writing to, and overcoming security of this hardware.

Aural Twitter

December 21, 2009 by Devlin Thyne 4 Comments

[POTUSCamacho] listens to his @public_timeline rss feed. In part one of his project, he describes creating a bash script in which he uses cURL get his private feed, sed to clean it and eSpeak to output a WAV file. In parts two and three, he goes on to discuss how he created an audio stream (currently down, opens in a new window) of @public_timeline and how he plans on tweeting vocally.

Better Resistors From A Pencil

December 20, 2009 by Jakob Griffith 37 Comments

Many of us here in the office (myself included) can’t tell the difference, but the audiophiles out there who want the best sound from their resistors should check out [Troel’s] write-up for making your own non-inductive graphite resistors. Graphite resistors have the traits for being non-inductive, have a negative temperature coefficient, and supposedly sound better. We liked the detail of his tutorial and how he gives many examples for making your own graphite resistor.

[Thanks Maxime]

Better Temperature Readings Using An Aspirated Thermometer

December 17, 2009 by Jakob Griffith 15 Comments

Unlike regular thermometers that can get incorrect readings because of the sun’s heat, shading, and airflow, aspirated thermometers isolate the temperature sensor from precipitation and the sun, while providing constant air circulation. Take ten 1-wire T2SS boards and combine them with DS18B20s and you’ve got yourself the start of an aspirated thermometer. A foot of PVC pipe, fans, and the above mentioned parts and you’ll have accurate temperature readings in no time.

[Dave] made his to control a natural gas boiler, pumps, and 11 gas-fired unit heaters for a combined output of 5.3 million BTUs per hour – keeping his greenhouse nice and toasty.

Update: Thanks Firetech for pointing out our silly typo.

Static Bleeder

December 17, 2009 by Caleb Kraft 31 Comments

When you are in the middle of the desert, pretty much every solution to a mechanical or electrical problem is a hack. [Sgt.M] who was deployed in Iraq sought out the help of radio guru [H.P. Friedrichs] about a static problem he was having. When dust storms would blow in strange things would happen in camp. Humming and crackling could be heard and [Sgt. M] actually had an electrical arc from a lamp to his hand at a distance of about 2 feet.

[Friedrichs] helped him find the problem. Their antennae were acting as static electricity collectors in the dust. All that dust friction in the dry air constantly built up a charge. The solution was simple, discharge the electricity at the antenna when it isn’t in use. Several solutions are outlined on the page, so check them out.

Make Magazine – Open Source Hardware 2009

December 15, 2009 by James Munns 5 Comments

Former HaD’er [Phillip Torrone] has written an extensive collection of Open Source Hardware projects for Make Magazine. This impressive list covers over 125 projects and kits, broken into 19 categories including 3d Printing, Music, Robotics, and Wireless systems. A number of these projects have been either extensively detailed or mentioned on HaD, so there is bound to be something for everyone here.

[Phillip] is not only detailing these projects for people new to the Open Source Hardware movement, but is also calling for new and unheard of projects to be listed in places like this, as well as central locations such as the OSH Wikipedia page. We are sure that a number of HaD readers will be answer this challenge.

Thanks again to [Phillip] for sharing this with us.