Le moteur à courant continu - Tuto Arduino - Le blog d'Eskimon Nul doute que vous connaissez l’existence des moteurs car il en existe toute une panoplie ! Le premier qui vous viendra certainement à l’esprit sera le moteur de voiture, ou peut-être celui présent dans une perceuse électrique. Voilà deux exemples d’objets dans lesquels on peut trouver un moteur. Bien entendu, ces deux moteurs sont de type différent, il serait en effet peu probable de faire avancer votre voiture avec un moteur de perceuse électrique… et puis l’utilisation d’une perceuse intégrant un moteur de voiture de plusieurs centaines de kilos serait fastidieuse . Sommaire Un moteur, ça fait quoi au juste ? Commençons en douceur par l’explication de ce à quoi sert un moteur et son fonctionnement. Ce chapitre n’est pas un des plus simples car il va faire apparaître des notions de mécanique qui sont indispensables pour comprendre le mouvement. Prenons un moteur électrique des plus basiques qui soient : Transformation de l’énergie électrique en énergie mécanique Un moteur ça fait quoi ? .
What Can You Do With A Slide Rule? Peter Alfeld, --- Department of Mathematics, --- College of Science --- University of Utah There was a time when electronic calculators did not yet exist. This did not stop us from doing complicated things, like going to the moon, figuring out the double helix, or designing the Boeing 747. In those days, when we needed to compute things, we used slide rules which are marvelous and beautiful instruments! There are many pages about slide rules on the web, and you can still buy brand new slide rules (40 years old but never used, and still in their factory supplied box) in various places. The purpose of this particular and quite idiosyncratic slide rule page is to describe common scales used on slide rules, and the kind of mathematical expressions that could be evaluated with those scales. The two images on this page show the two sides of a particular slide rule in my collection. German made slide rules of that time (the late 1960s) usually come with an accessory plastic ruler. Why? . .
Decoding the Secret Language of Food Expiration Dates Americans tend to harbor dark suspicions about that forgotten can of beans in the back of the pantry, far past its sell-by date. If you’re like most consumers, you probably just toss expired items on the better-safe-than-sorry principle (unless, perhaps, it’s a Twinkie). But there’s a good chance many aged food remains totally safe to eat, according to a new report (PDF) that blames the flawed food-dating system for tons of perfectly edible food getting wasted each year. While many consumers consider the dates printed on foods a hard deadline, they actually indicate maximum quality or freshness, not safety, explains David Fikes, vice president in charge of consumer affairs at the Food Marketing Institute (FMI), a food trade group. “Producers want people to have the best experience of product,” he says. There’s a window after the “expiration” date when a product is still edible—it just won’t look or taste quite as good. • Pack date: This is the day the product was manufactured.
Slowing 198.27.81.81&c=1&t=42173.03009375 This page details the use of Epson^ InkJet printers with pigment based inks to feed and directly print resist patterns to copper clad printed circuit board stock, ready for etching. Once you can feed the PCB through the printer for etch resist, you can then feed it back through the printer for solder mask (yes! Several people report that it works quite well!) and for a component "silk-screen". Toner transfer is probably easier to set up for and may be as fast, but direct ink is more precise, allows solder mask and component printing in the appropriate color, and most importantly, finer traces and spaces! The secret (discovered by Volkan) is that certain pigment based inks, such as MISPRO Inks^ (#MISPRO42-SET-MK) can be cured with heat to form a very strong resist. Barry Cooper^ reports^ that Epson ultra chrome k3 ink in his Epson R2400 printer also resists etchant if fully cured. Printer Modifications: "I am currently using 1/16" [PCB stock]. CD/DVD printing trays. Process PCB Preparation
Cauliflower Soup I’m going to let you in on a little secret. Come closer now…come closer. Lean in. Okay, so I just made a big deal out of nothing. Keep in mind that while this soup may appear to have a lot of steps, there’s nothing difficult about it. Here’s what you’ll need: The Cast of Characters: Cauliflower, Carrot, Onion, Celery, Chicken Broth or Stock, Milk, Half & Half, Butter, Flour, Salt, Pepper, Sour Cream, and Parsley (fresh or dried). Wash 1 to 2 heads of cauliflower, depending on how chunky you’d like the soup to be. Just whack the head in half and get rid of the hard inner core and green parts. Then just roughly chop the cauliflower. You could be meticulous and cut the cauliflower into neat little florets…but why? Next, finely dice one carrot. I do the same to the celery: just cut it into strips, then dice. Same goes with the onion: first cut lines/strips… Then dice away! Then say the following word: Mirepoix, pronounced “mi-reh-pwah.” Throw in the carrots and celery… Stir it around to combine…
Electronics Tech Tips When working with SMT components, a solder-paste silk screen method plus a good baking in a special oven to make the paste flow works best. But for most of us working on small projects with a limited budget, angel hair solder and a fine tip iron that is ESD safely grounded is the way to go. Those new to SMD components may struggle with "tomb stoning," which happens when one end of the component is soldered and the other end pops up in the air. Here's an easy solution. You will need to use both hands (assuming they do not shake too much) one to hold the Iron and solder and the other to hold down the passive component with a small tool or tooth pick until the iron is removed and the solder has solidified. Bruce Weidner Columbus, Ohio Alternative PCB Etchant I thought I would share my experiences with creating quality circuit boards using household supplies as an etchant. I set out to create an etchant that, by my calculation, would be roughly 8 times cheaper than ferric chloride. Supplies:
27 Medicinal Plants Worth Your Garden Space Please be sure to Join our email list and receive all our latest and best tutorials daily – free! We’ve discovered a fantastic article listing 27 of the top medicinal plants – together with details of their potential uses. These plants can be really handy to have around if you know their value. One thing I would suggest is to print out the full article (you might need to do a little copy-pasting and tidying up) and then keep the printout together with your first aid kit. We’ve summarized the list here with links to our own full length articles on the herbs. To this list I would certainly add Lavender, Rosemary, Garlic and Oregano! Note – articles on herbs-info.com are not medical advice and are not meant to be a substitute for a consultation with a medical professional, nor a recommendation to self-medicate. I Can't Help Showing This Off: If you haven't heard of Claude Davis yet do yourself a huge favor and watch this video. >>> Watch His Short Video <<< Watch the video to see what happens:
Schematic Publisher Beta 1.0 RJWSoft Schematic Publisher is a complete schematic capture and publishing system. Schematic Publisher is perfect for students, hobbyists, and professionals. by Ray Wilson RJWSoft Schematic Publisher is a complete schematic capture and publishing system. Schematic Publisher is perfect for students, hobbyists, and professionals. Courtesy/Thanks to: Ray Wilson Description: By Ray Wilson: RJWSoft Schematic Publisher is a complete schematic capture and publishing system. What do I ask in return you say...? Easy to use functionality featuring: Schematic Capture, Edit & Print Schematic Publisher lets you create and edit schematic components and use them to create electronic schematic diagrams. Easily compose, edit and print schematic components, multi-page schematics, and panel diagrams. Zoom in for easy editing and component placement. Preview you schematics or lists prior to printing. Create, edit and save new schematic components in seconds for use in your diagrams. there is no limit to the type of components you can create from ICs to tubes. Wire List Generation Once your schematic is complete a wiring net list is just a mouse click away. Part List Generation
Immune Boosting Herbs Please Share This Page: Top 20 Immune Boosting Herbs - image to repin / shareHerbs background pic © CLIPAREA.com - Fotolia.com Aside from keeping common colds and flu away, the immune system is your body's first and best defense against potentially lethal diseases like H1N1 and even cancer. [1] It is comprised of a network of cells and organs working together to defend the body against infection and sickness by producing secretions and disease-fighting cells. It uses an advanced communications system to respond to immediate threats. [2] The complex efficiency of your immune system and how it works non-stop indeed signify its importance for your health. If the immune system weakens and malfunctions, imagine the host of diseases that can invade your system. Here are ten herbs which may be helpful in supporting your immune system. 10 Immune Boosting Herbs Echinacea Astragalus Panax Ginseng Garlic Ginger Cat’s Claw Oregano Turmeric Bell Pepper Cloves Immune Boosting Herbs - References:
Front End Turns PC Sound Card into High-Speed Sampling Oscilloscope. Part 1 - End, Clock Generator By Doug Mercer, Analog Devices Various software packages enable the stereo sound card found in a personal computer (PC) to provide oscilloscope-like displays, but the low-sample-rate, high-resolution analog-to-digital converters (ADCs) and ac-coupled front end are optimized for 20 kHz or less of usable bandwidth. This limited bandwidth can be extended – for repetitive waveforms – by using a sampling front end ahead of the sound card inputs. Subsampling the input waveform with a high-speed sample-and-hold amplifier (SHA) – followed by a low-pass filter to reconstruct and smooth the waveform – effectively stretches the time axis, allowing the PC to be used as a high-speed sampling oscilloscope. Figure 1 shows a schematic for a plug-in attachment that can be used for sampling with typical PC sound cards. The AD783 SHA provides a usable large-signal bandwidth up to a few megahertz. Another screen shot was taken of a Gaussian sine pulse with a 1-MHz repetition rate (Figure 3). analog.com
Perfect Potato Soup I’m Pioneer Woman and I have a confession to make. Are you ready? Here goes. *Ahem.* *Clearing my throat.* *Singing a couple of scales to warm up I’m picky about potato soup. It’s true. It can’t be too creamy, with no variance in texture. It can’t be too lumpy. It has to be full of flavor or I’ll die a thousand deaths. And most of all…it has to make me close my eyes, sigh, and feel like everything till the end of time is going to be okay. But other than those things, I’m not the least bit picky about potato soup! Here’s how I make it: The Cast of Characters: Small Russet potatoes, carrots, celery, onions, milk, flour (not pictured, because I’m an airhead), heavy cream, salt, pepper (not pictured, for the same aforementioned reason), Cajun spice (ditto), parsley, and thin bacon. Gosh, I’m thorough with these Cast of Characters set-ups, aren’t I? Not. Start by slicing the bacon into small pieces… This is about six slices. Throw the bacon into a soup pot over medium heat… To dice! Cut them into sticks…