IM-ME Spectrum Analyzer

March 17, 2010 by Mike Szczys 27 Comments

[Michael Ossmann] rolled out some firmware that makes his IM-ME into a Spectrum Analyzer. He met up with [Travis Goodspeed], who authored the IM-ME flashing guide, at SchmooCon and spent some time hacking wireless doo-dads in the hotel bar. Once he arrived home the new firmware was just a few coding sessions away from completion. It scans one frequency at a time, displaying the results in a 132 column graph on the screen. He also added a ribbon cable and header to the debug contacts so that future hacking would be as simple as plugging in the GoodFET.

[Thanks Jared and Travis]

Soil Moisture Sensing

March 15, 2010 by Mike Szczys 31 Comments

These plugs are cheap, easy to make, and work well for measuring the moisture content of soil. The Cheap Vegetable Gardener came up with this method in order to add automatic watering to an automated grow system. Plastic tubing is used as a mold for Plaster of Paris. Once the plaster has been poured, two galvanized nails are inserted. These are won’t rust and work as probes, measuring the resistance of the dried plaster (gypsum). When inserted into the soil, the moisture content within the gypsum will fluctuate along with the soil. As moisture rises, the resistance between the probes falls, which can be monitored by a microcontroller and used to trigger or stop a watering system.

[Thanks Juan]

Easy IM-ME Flashing

March 12, 2010 by Mike Szczys 19 Comments

[Travis Goodspeed] wrote a guide to firmware flashing for the IM-ME. He’s using a GoodFET open-source JTAG adapter that he designed to do the programming. This is really taking [Dave’s] work on the device and running with it. The end goal being to develop an operating system for the device. If you haven’t read the past articles, once hacked this becomes a development board for the Chipcon CC1110 processor with keyboard, LCD screen, and wireless communications included.

50MHz To 100Mhz Scope Conversion

March 10, 2010 by Mike Szczys 96 Comments

[Ross] is the proud owner of a 50 MHz Rigol DS1052E oscilloscope. He’d like to have the 100 MHz version but the $400 difference in price puts it out of his reach. After some extensive poking around on the PCB and pouring over datasheets, he managed to reverse engineer the design and upgrade to a 100 MHz version. This is as easy as desoldering one capacitor to deactivate a high-pass filter present in the lesser model of scope, unlocking the faster potential of its bigger brother.

Jeri Makes Integrated Circuits

March 10, 2010 by Mike Szczys 38 Comments

[Jeri Ellsworth] made this silicon inverter at home, by hand. It took her two years to get the process figured out and achieve something we didn’t think was possible. The complexity of manufacture, and the wide range of tools and materials needed seem insurmountable but she did it anyway. Her home chip fab Flickr set is well commented and details her work area and part of the processing. If you’re hurting for more check out her 40 minute Metalab talk which we’ve embedded after the break.

If her name sounds familiar but you just can’t place it you may know her from The Fatman and Circuit Girl. We’ve also featured some of her hacks, such as her Pinball challenge against [Ben Heckendorn], and her giant Etch-a-Sketch.

Continue reading “Jeri Makes Integrated Circuits” →

Time Delay Door Alarm

March 6, 2010 by Caleb Kraft 21 Comments

Ever accidentally left your front door ajar and had a pet escape? [BlackCow] came up with a simple solution to this problem. The circuit is fairly rudimentary but a great example of using the basics to get the job done. Now, instead of having an alarm that sounds as soon as the door is open, he has a 30 second delay. This helps avoid the “boy who cried wolf” effect also known as the “vista security warning” effect of being bothered too many times for a non issue. We also have to say that we like his taste in blog layouts.

[via Hacked Gadgets]

DIY Diodes

March 5, 2010 by Devlin Thyne 47 Comments

[H. P. Friedrichs], the creator of the Static Bleeder has created his own diodes. Using household chemicals, a film of cuprous oxide was made on a copper pipe cap. Cuprous oxide has been one of the first known semiconductor substances, has a low forward drop but is an otherwise asymmetrical conductor, odd V-I curves, and some neat photovoltaic action. The apparatus seen above is used to bring a piece of lead (in this case, solder) into contact with the salmon-colored cuprous oxide while electrical connections can be made to the binding posts at the front. What are your thoughts on this device?