6/30/2012

.45 ACP CRISAT Ballistic Gel

6/29/2012

Kicad symbol generating script

Kicad symbol generating script shows promise

posted Feb 17th 2012 7:01am by Mike Szczys
filed under: tool hacks

Kicad is a fantastic PCB layout tool. We think creating a part for use with Kicad is in many ways easier than in Eagle, but it never hurts to have a few shortcuts. Here’s a new way to quickly get your parts into the schematic editor. It’s a Python script that generates symbols from an XML input file. You create the XML file with a list of all the pins on your part and the function they will serve. The Python script will then format that as a library file which can be imported by Kicad.

It’s a little bit clunky due to the number of steps in the process. But it is possible to use a CSV file generated in a spreadsheet program to create the XML needed by the script. We’ve used the online component builder ourselves, and appreciate the possibility of mass pin assignments instead of the drop-box for every pin as used by the web interface. One time we were 20 pins into the naming process and accidentally refreshed the page… ugh!

The code is available in their git repository, with a description of the XML format, and a wiki tutorial outlining the component building process. After you give it a try we’d love to hear what you think in the comments.

6/28/2012

Solder Paste, Toaster Oven, Homemade Vacuum Pickup Reflow Demo

Arduino-based logic displays

VIA: http://www.barrettandcarly.com/blog/elec/DroidLightsV2.html

Arduino-based logic displays

NOTE! The files below are the version 2 board design which has been superseded by the version 3 design. The version 3 information is on this page.

FreePCB (fpc) files. Download these if you want to edit or just view the board designs in the FreePCB application.
V2 front logic PCB file
V2 Rear logic PCB file
Gerber files. You can use these files to order a set of boards from pcb.laen.org, or your favorite fabricator. You can also view or print the gerber files with GC-Prevue.
V2 Front logic gerber
V2 Rear logic gerber
Here's a sketch with scrolling text and random display.
I drew these using FreePCB. If you don't already have it, you'll need to install all of the updates on the downloads page, including the latest "unstable" executable and the 2 files listed under "New header footprints with larger hole and pad sizes".
Also, please add the following text to the top of the th_capacitor.fpl file. This adds a part called CKJV which is defined as a capacitor, but I'm using it as a connection point for a screw terminal. If anyone knows the "correct" way to add a screw terminal in FreePCB, please let me know.

--- cut here (start) ---

name: "CKJV"
author: "JMV"
source: "made up"
 units: MIL
 sel_rect: -46 -58 246 58
 ref_text: 50 100 80 0 7
 outline_polyline: 7 -80 70
   next_corner: 280 70 0
   next_corner: 280 -70 0
   next_corner: -80 -70 0
   close_polyline: 0
 n_pins: 2
   pin: 1 52 0 0 0
     top_pad: 1 94 47 47
     bottom_pad: 1 94 47 47
     inner_pad: 1 94 47 47
   pin: 2 52 200 0 0
     top_pad: 1 94 47 47
     bottom_pad: 1 94 47 47
     inner_pad: 1 94 47 47

--- cut here (end) ---

Now that we've got that out of the way, I'll describe the theory of the circuit.
The design is based on the MAX7219 LED driver IC from Maxim. This driver has several properties that make it attractive for use with Arduino:

it can control 64 LEDs (8x8 matrix) using only 3 output pins
they can daisy chain together to control even more LEDs, still requiring only the 3 pins
there is already an Arduino library developed specifically for this IC.

And, they're cheap. I bought some on eBay for $1 each (I got 8 of them for about $10 including shipping).
Also they don't require you to place a resistor in the circuit for each LED. A single resistor labeled RSet is used to set the upper limit on the current sent to all the LEDs.
Since the driver IC is capable of controlling more than the 45 LEDs in the front logic matrix, my original version of the front board included an "extra" row of 8 LEDs positioned below the IC. This extra row was intended to give a place to hook up additional LEDs that you would need in addition to the logic displays, such as HP or PSI. I wound up removing this extra row for 2 reasons: There's no way that LEDs driven by the MAX7219 would be bright enough for PSI or HP. Those have to be VERY bright. Also, the extra row made the board too tall, and it wouldn't clear the bearing adapter ring in the bottom of the dome.
Also, you'll notice that the 5x9 matrix has 9 columns, whereas the driver IC only supports 8 columns. To get this 9th column, I simply added an extra row to the matrix, then rotated and moved that row to the 9th column. After all, the notion of "rows" and "columns" is purely conceptual and the LEDs themselves can be positioned anywhere, as long as the circuit can be made.
Finally, the circuit is designed with "IN" and "OUT" signal headers. You could hook these up as follows:
output from 3 Arduino pins to the bottom FLD "IN";
connect bottom FLD "OUT" to the top FLD "IN";
connect top FLD "OUT" to the RLD "IN"

That's it. In your Arduino sketch, you would create an LEDControl object:

LedControl lc=LedControl(12,11,10,5);

so we would use pins 12,11 and 10, and we specify that we have 5 driver ICs. From that point we can turn any LED on or off.

//turn on the 3rd row, 8th column of the first driver
lc.setLed(0,2,7,true);

//turn off the 4th row, 5th column of the second driver
lc.setLed(1,3,4,false);

Here are the bare boards as they arrive from pcb.laen.org

Some pictures of the built-up boards with the LEDs inserted but not soldered yet. The RLD back...

The RLD front...

The RLD with Joymonkey's CNC-cut bezel

The FLD back...

The FLD front with bezel...

Parts List

item	each	qty	total	source	part #	Incl shipping?	notes
rld board 6.51 sq. in.	10.85	1	10.85	pcb.laen.org		y	must order multiples of 3
fld board 2.354 sq. in.	3.92	2	7.84	pcb.laen.org		y	must order multiples of 3
LED	0.025	225	5.625	eBay		y	must order 3 lots; each lot contains 20 of each color (R, G, Y, W, B); cost 2.49 per lot
DIP24 socket	0.27	5	1.35	Digi-Key	3M5466-ND	n
MAX7219	1.00	5	5	eBay		n	order 1 or 2 extra
cap 10uF	0.52	3	1.56	Digi-Key	445-2863-ND or 445-2874-ND	n
cap 0.1uF	0.15	3	0.45	Digi-Key	490-5369-ND	n
resistor 24k for fld	0.06	2	0.12	Digi-Key	24KH-ND	n
resistor 28k for rld	0.11	1	0.11	Digi-Key	28.0KXBK-ND	n
screw terminal	0.46	3	1.38	Digi-Key	ED1609-ND	n
double row header strip	0.03	3	0.09	eBay		y	sellers typically offer strips of 40+ pins; break off groups of 3
14-inch 3-wire F/F Extension Cable	2.50	3	7.50	parallax.com	805-00002	n	you can occasionally find these on eBay for MUCH cheaper, more like $5 for 12 pcs.
total			41.875

The LEDs I used are readily available on eBay. Search for this text: "100 3mm Red Green Blue". Sort by price, lowest first. The first one in the list should be $2.49 shipped, and includes 20 of each color (R, G, Y, W, B); order 3 sets of those, total cost $7.47. It will be more than enough to do all 3 displays. Some of them turn out to be flanged while others are not. For the flanged ones, clip off the flange with a set of nail clippers. Clipping the flange is a breeze once you've done a few. Then cut the leads short before inserting into the board.
Note that this is just one of many sources for LEDs! If you know of other good sources, let me know and I'll add them to this page.
I have made a simple tutorial for building the front display.

Ordering boards from pcb.laen.org

I chose to order the boards from pcb.laen.org because he's a great guy to work with and has fast turnaround time. He fabs the boards in sets of three, so your order would be placed as "I would like one set of 3 boards", or "I would like two sets of 3 boards" etc. Since an astromech requires one rear and two front boards, one reasonable approach would be to order one set of (3) rear boards and two sets of (3) front boards. This would give you 3 rear and 6 front boards, which would be enough to do three droids. Then you could order enough parts from the parts list above for 3 sets and split the shipping costs 3 ways, further reducing the per-droid cost. John Vannoy
March 2011

6/27/2012

ATX to Lab Bench Power Supply Conversion

Matthew Beckler's Home Page

Home :: General :: Software :: Hardware :: Microcontrollers :: Artsy Things

ATX to Lab Bench Power Supply Conversion

In my sophomore year of college at the University of Minnesota, I started into my main electronics classes, and needed a good power supply for working on the lab projects at home in my room. My roommate Adam told me about somebody online who had converted a spare ATX computer power supply into a lab bench power supply, so I decided to try and do the same thing. I scrapped the power supply from the PJRC MP3 Player, and started the conversion.

When I opened up the power supply, I found the following wires inside:

+3.3V
+5V
+12V
-12V
+5V Standby (Always On)
Power_On
Power_Ok
Ground

I connected the +5, +12, -12 voltage rails through individual 1 Amp fuses to the front binding posts. I connected the ground connection directly to the front binding post. I connected the switch between the Power_On signal and Ground. When the Power_On signal is connected to Ground, the power supply will turn on. I connected the +5V Standby through a resistor and LED to ground, which is useful as a "plugged in" indicator LED. The Power_Ok signal goes high (+5V) when the power supply has settled down after startup, and all voltages are in their proper ranges. It is connected to the other LED through a resistor. There is also a 10 Ohm, 10 Watt power resistor between +5V and Ground. It is used to provide a small load to keep the power supply in the On mode.

Note: While the diagrams show fuses on all voltage rails and no fuse on the ground line, when I actually built my power supply, I was young and foolish and only put a fuse on the ground wire. It's much safer and a better idea to put fuses on all signal lines and not the ground line. Thanks to many emails and messages on Instructables about this oversight.

I have included a handful of pictures here with descriptions, but all the pictures are available in my Lab Bench Power Supply group on Flickr

This project is also documented on the Instructables website.

	This is the original drawing I made to plan out the conversion.
	This is the circuit diagram to show how to connect everything.
	Here you can see my drawings on the side of the case. I had removed the insides so I could safely drill the holes. In this picture, the hole for the first binding post has been drilled, and I have marked out the locations of the fuse holder and power switch.
	Finished drilling all four binding posts, as well as the pilot hole for the power switch. Yes, I am working in a garbage can, so the metal shavings don't get in the carpeting.
	Test fitting all four binding posts, the fuse holder, and power switch.
	I added two LED indicators to the front. Here you can see the back-side of the LED holders. They will be used to indicate "Standby (Plugged In)" and "Power On (Switch On)".
	Here, I started to connect the binding posts to their proper wires. I have connected the +5V and GND in this picture. You can also see the LED's on the right side of the picture.
	In this picture, you can see two green LED's in the holders. I eventually switched to red LED's because I have many more red ones than green ones. At this time I had already finished connecting all four binding posts.
	Here, I have connected all the binding posts, the indicator LED's, and the power switch.
	You can see the 10 Ohm, 10 Watt, power resistor connected to the back wall of the power supply. It connects 5V and GND, which provides a load to keep the power supply operating when I don't have anything connected to it.
	I used regular breadboard wire to attach the power resistor to the back wall of the case.
	The finished product, with the lid off.
	Another view of the finished power supply.

Discharge Power Supply Capacitors using 22 ohm 20 watt resistor (Blue Shown)

Step 2Safety

There are many ways that you can electricute yourselfs when doing this project, so please take the following precautions building this project, and don't get shocked and get a big blister like I did.

**NEVER EVER WORK ON YOUR POWERSUPPLY WHILE IT IS PLUGED IN**
*The capacitor inside holds enough electricity to cause an extremely painful shock, so discharge these capacitor with a power resistor with resistance over 10k ohm, just bend the resistor leads to the capacitor leads on back of the circuit board and make sure you hold the resistor with a pair of pliers because they tend to get very hot.

Big News: Introducing Nexus 7

6/26/2012

Chrome OS

How to Install Chrome OS in Windows 7

By Taimur Asad | November 21st, 2009

6/24/2012

Magnetic refrigerator successfully tested

Ames Laboratory develoments help push boundaries of new refrigeration technology

(left to right) Vitalij Pecharsky, David Jiles, and Karl Gschneidner are helping push the advancement of magnetic refrigeration. Earlier this fall, the first room-temperature, permanent-magnet magnetic refrigerator was successfully tested by Astronautics Corporation of America, a research partner in the project with Ames Laboratory.

Using materials developed at the U.S. Department of Energy's Ames Laboratory, researchers have successfully demonstrated the world's first room-temperature, permanent-magnet, magnetic refrigerator. The refrigerator was developed by Milwaukee-based Astronautics Corporation of America as part of a cooperative research and development agreement with Ames Laboratory.

Instead of ozone-depleting refrigerants and energy-consuming compressors found in conventional vapor-cycle refrigerators, this new style of refrigerator uses gadolinium metal that heats up when exposed to a magnetic field, then cools down when the magnetic field is removed.

"We're witnessing history in the making," Ames Laboratory senior metallurgist Karl Gschneidner Jr. says of the revolutionary device. "Previous successful demonstration refrigerators used large superconducting magnets, but this is the first to use a permanent magnet and operate at room temperature."

Initially tested in September at the Astronautics Corporation of America's Technology Center in Madison, Wis., the new refrigerator is undergoing further testing. The goal is to achieve larger temperature swings that will allow the technology to provide the cooling power required for specific markets, such as home refrigerators, air conditioning, electronics cooling, and fluid chilling.

According to Gschneidner, who is also an Anson Marston Distinguished Professor of materials science and engineering at Iowa State University, the magnetic refrigerator employs a rotary design. It consists of a wheel that contains segments of gadolinium powder — supplied by Ames Laboratory — and a high-powered, rare earth permanent magnet.

The wheel is arranged to pass through a gap in the magnet where the magnetic field is concentrated. As it passes through this field, the gadolinium in the wheel exhibits a large magnetocaloric effect — it heats up. After entering the field, water is circulated to draw the heat out of the metal. As the gadolinium leaves the magnetic field, the material cools further as a result of the magnetocaloric effect. A second stream of water is cooled by the gadolinium. This water is then circulated through the refrigerator's cooling coils. The overall result is a compact unit that runs virtually silent and nearly vibration free, without the use of ozone-depleting gases, a dramatic change from the vapor-compression-style refrigeration technology in use today.

"The permanent magnets and the gadolinium don't require any energy inputs to make them work," Gschneidner says, "so the only energy it takes is the electricity for the motors to spin the wheel and drive the water pumps."

Though the test further proves the technology works, two recent developments at Ames Laboratory could lead to even greater advances on the magnetic refrigeration frontier. Gschneidner and fellow Ames Lab researchers Sasha Pecharsky and Vitalij Pecharsky have developed a process for producing kilogram quantities of gadolinium-silicon-germanium alloy using commercial-grade gadolinium. The Gd5(Si2Ge2) exhibits a giant magnetocaloric effect that offers the promise to outperform the gadolinium powders used in the current rotary refrigerator.

When the alloy was first discovered in 1996, the process used high-purity gadolinium and resulted in small quantities (less than 50 grams). However, when lower-quality commercial-grade gadolinium was used, the magnetocaloric effect was only a fraction of that found in the original alloy, due mainly to interstitial impurities, especially carbon. The new process overcomes the deleterious effect of these impurities, making it viable to use less-expensive commercial-grade gadolinium to achieve roughly the same magnetocaloric effect as the original discovery.

At the same time, Ames Lab researchers David Jiles and Seong-Jae Lee, along with Vitalij Pecharsky and Gschneidner, have designed a permanent magnet configuration capable of producing a stronger magnetic field. The new magnet can produce a magnetic field nearly twice as high as that produced by the magnet used in the initial refrigerator; this is an important advance since the output and efficiency of the refrigerator is generally proportional to the strength of the magnetic field. The group has filed patent applications on both the gadolinium alloy process and the permanent magnet.

"These are important advances, but it will require additional testing to see how much they will enhance refrigeration capabilities," Gschneidner says. "Progress (in this field) is measured in small steps, and this is just another of those steps. However, we've come a long way since first announcing the giant magnetocaloric alloy five years ago."

Epson PCB Printer by Kinslayer

Makino's ADVANTiGE Technologies Improve Titanium Milling

6/22/2012

ITEC 2012 VBS2 2.0 Full Length

A u t o n o m o u s M i l i t a r y R o b o t i c s : R i s k , E t h i c s , a n d D e s i g n

"These robots would be ‘smart’ enough to make decisions that only humans now can; and as conflicts

increase in tempo and require much quicker information processing and responses, robots have a

distinct advantage over the limited and fallible cognitive capabilities that we Homo sapiens have.

Not only would robots expand the battlespace over difficult, larger areas of terrain, but they also

represent a significant force-multiplier—each effectively doing the work of many human soldiers,

while immune to sleep deprivation, fatigue, low morale, perceptual and communication challenges

in the ‘fog of war’, and other performance-hindering conditions. But the presumptive case for deploying robots on the battlefield is more than about saving human

lives or superior efficiency and effectiveness, though saving lives and clearheaded action during

frenetic conflicts are significant issues.

Robots, further, would be unaffected by the emotions,

adrenaline, and stress that cause soldiers to overreact or deliberately overstep the Rules of

Engagement and commit atrocities, that is to say, war crimes. We would no longer read (as many)

news reports about our own soldiers brutalizing enemy combatants or foreign civilians to avenge the

deaths of their brothers in arms—unlawful actions that carry a significant political cost. Indeed,

robots may act as objective, unblinking observers on the battlefield, reporting any unethical behavior

back to command; their mere presence as such would discourage all-too-human atrocities in the first

place."

Make Ready with Jessie Abbate: a Woman's Guide to USPSA

HOT. Wouldn't you know it but she only gets a 480p res. video. :( Still awesome demo though.

6/19/2012

HHO 354 Plate Monster Hydrogen Generator Build Part 2

Police have no duty to protect

Federal judge kicks out part of Chicago's gun law

Ban on permits for those convicted of unlawful use of weapon is called unconstitutional

The city must now decide whether to appeal the ruling or rewrite the part of its gun ordinance that bars individuals convicted of even misdemeanor offenses from possessing a firearm in their home for self-defense. (Zbigniew Bzdak, Chicago Tribune / February 28, 2012)

By Dahleen Glanton and Liam Ford, Chicago Tribune reporters

June 20, 2012

Chicago's firearm ordinance took another blow Tuesday when a federal judge ruled that the section banning permits for people convicted of unlawful use of a weapon is vague and unconstitutional.

The ruling came in a lawsuit filed by Shawn Gowder, who claimed his constitutional right to bear arms was violated when he was denied a firearm permit two years ago because of a misdemeanor conviction for possessing a gun on a public street.

The lawsuit, backed by the National Rifle Association, is one of at least five cases pending against the city's gun ordinance, which was passed in 2010 just days after theU.S. Supreme Court struck down the city's 28-year ban on handguns. The Illinois State Rifle Association also filed a brief in support of Gowder.

The decision by U.S. District Judge Samuel Der-Yeghiayan addresses only a part of the ordinance that relates to applicants who have been convicted of unlawful use of a firearm. Federal lawsuits are still seeking to overturn the city's ban on retail gun stores and to remove restrictions forbidding guns from yards and on front porches.

City officials said they are reviewing the ruling and will advise police on how to proceed with enforcing the law. Since it applies only to one provision of the ordinance, a City Hallofficial said, city attorneys do not believe the ruling will have a significant impact on the entire ordinance.

The judge ruled that the city's ordinance does not adequately define "unlawful use of a weapon," noting that it can mean different things in different jurisdictions.

"There is something incongruent about a nonviolent person, who is not a felon but who is convicted of a misdemeanor offense of simple possession of a firearm, being forever barred from exercising his constitutional right to defend himself in his own home in Chicago against felons or violent criminals," Der-Yeghiayan wrote.

"The same Constitution that protects people's right to bear arms prohibits this type of indiscriminate and arbitrary governmental regulation," he continued. "It is the opinion of this court that any attempt to dilute or restrict a core constitutional right with justifications that do not have a basis in history and tradition is inherently suspect."

Gun rights advocates hailed the ruling as a victory for Second Amendment rights.

"The only thing Mr. Gowder did was to own a firearm. As a result, he was treated like a criminal by the city of Chicago when all he did was exercise his fundamental Second Amendment right," said Stephen Kolodziej, a Chicago attorney representing the plaintiff. "We think the city of Chicago's actions in denying Mr. Gowder a firearm permit were punitive and draconian as well as violative of his constitutional right to keep and bear arms."

Gowder was denied a firearm permit in 2010 because of a 1995 misdemeanor conviction for possession of a firearm on a public street. At the time of his conviction, the offense was classified as a felony, but the Illinois Supreme Court in 1999 struck down the Safe Neighborhood Act, which classified simple possession of a firearm as a felony, and made it a misdemeanor.

Gun advocates have long opposed laws that summarily banned those even with convictions for nonviolent felonies from obtaining a legal weapon. They have argued that several factors should be considered, including the nature of the prior conviction and the length of time that has passed since it occurred.

Brian Koukoutchos, a Manderville, La., attorney who also represents Gowder, said: "Some thought needs to be given to what the nature of the crime is."

"You have to be careful when you allow run-ins with the law to automatically strip someone of their rights," he said.

dglanton@tribune.com

Iford@tribune.com

Twitter @ltaford

4409 -- THE TRUTH WHY RAND PAUL ENDORSED ROMNEY

6/18/2012

Nanomaterials for Batteries & Energy Storage

6/17/2012

Apple 1 computer and Steve Jobs Atari memo sold at auction

http://www.bbc.com/news/technology-18456746

Fascinating Design. Great links to more reference boards. Very interesting insight into the Apple corporation.

Apple 1 computer and Steve Jobs Atari memo sold at auction

The Apple 1 was sold as an exposed motherboard

A rare functioning Apple 1 computer - the company's first product - has been sold at an auction for $374,500 (£240,929).

The price was more than double Sotheby's high estimate and sets a new record for the collector's item.

A memo written by the firm's co-founder Steve Jobs when he worked at Atari sold for $27,500 at the same New York event.

The original estimate for the four-page handwritten note was up to $15,000.

Only about 200 Apple 1s were ever created. The computers were hand-built by Apple's co-founder Steve Wozniak and originally sold for $666.66 (£426) as a fully assembled circuit board.

He later said he picked a sum with a repeating number "because it was just an easier way to type".

Only about 50 Apple 1s are still believed to be in existence. The auctioned model is one of the very few that still works.

Sotheby's said there was a battle between two parties for the item which also included the original manuals. A set of bids was executed by the auctioneer on behalf of an absentee collector, but a telephone bidder proved more persistent and eventually clinched the sale.

The memo outlined ways to improve Atari's World Cup football game

Their identity has not been revealed.

Buddhist mantra

The Atari memo was written in 1974 and consists of four pages detailing the late Steve Jobs' thoughts on how to improve its arcade football game World Cup.

He was 19 years old at the time. The pages include circuit drawings and diagrams showing how the paddle-based game could be made more fun to play.

The notes are stamped with Mr Jobs' Los Altos home address and a Buddhist mantra - "gate gate paragate parasangate bodhi svahdl".

It translates as: "Going, going, going on beyond, always going on beyond, always becoming Buddha."

Sotheby's said there had been "at least three bidders" for the item.

The high sums are the latest confirmation of demand for memorabilia connected to Steve Jobs, who died last October.

Apple's founding papers, featuring Mr Jobs' signature, sold at auction in December for close to $1.6m.