Search for thin film in Topics


Thin Film Battery?

Hi, I was wondering what kind of battery chemistry I could use with thin film battteries. Something like a sheet of Material: A then a shet of paper Towel soaked in electrolyte, then Material: B. What should I use for Materials A and B? Aluminum foil/carbon paper, Aluminum foil, Copper Foil, Zinc Foil, Carbon Paper?

Question by LiquidLightning    |  last reply


hi, can anyone help with a laminating steel or brass with a thin film of silicon? Answered

Im buildng a mould for casing pcl (polymorf) there are issuse with using petroleum jelly as a release agent due to it clogging the pores, im building a highly porus biological scaffold for tissue engineering

Question by randomhand    |  last reply


Quantum Levitation

Wow, just in time for The Mad Science Fair- an awesome magnetic levitation set-up. The Superconductivity Group at Tel Aviv University have been working on thin-films of superconductive materials and have found some...cool effects.  The thin films will apparently have a few defects, resulting in very specific areas where the magnetic field permeates.  This rigidly constrains the composite, allowing even "up-side down" levitation! (locked in space, beneath a magnet.)  Would be so awesome to play around with but apparently the deposition of the superconductive film is a real challenge, not to mention the sapphire substrate. A forum post at HI Capacity had these links, probably after a member saw Gizmodo's article "What the Hell Magnets? Why Are You So Amazing?" Via youtube: ASTCvideos Quantum Levitation QuantumLevitation

Topic by CrLz    |  last reply


Building a hair thin Mini hot tip (like soldering)

Building a hair thin Mini hot tip (like soldering) Building a hair thin Mini hot tip (like soldering) Well as you read it I am trying to build a very very small heat controllable mini hot tip (max 40 degrees C) And definitely I am sure you are such an expert in the area that the hair hot tipwill sound like a joke to you. What for? well, long story short I want to put bacteria samples on it & gradually increase the temperature and see how the populations die or survive, and most likely how long they last, to demonstarte if actual dishwashers do a good job. (maximum temp boiling point) I actually want to record the video given to the fact that the microscope I have access at school is wayyyy more powerful than the rest. I know I should use an LED or just heat but what prevents me from doing so is just blowing away the samples from the tip or changing the exposure too much with extra lights. I believe the principle is almost the same as with the coil inside electric bulbs or the same as in ironing clothes but not as hot (in orders of magnitude) I believe the trick is driving voltage and just making variations to it with a dial please help I really want to see those bacteria and film them . All help will be appreciated Thanx Micro Freak apprentice

Topic by dejabox    |  last reply


how to design and build a solar power monitoring system?

Budget less than USD100, require a small solar panel(<100W will do), thin film type solar panel, need some voltage and current sensors, data acquistion card (which type of card shd i choose?) i will need to monitor its output voltage, current and power, how should i start?

Question by project_stress    |  last reply


photovoltaic CIGS solar cells DIY ..

Hello, I have been reading this document lately: CIS(CIGS) thin films prepared for solar cells by one-step electrodeposition in alcohol solution www.iop.org/EJ/abstract/1742-6596/152/1/012074/ and I have been wondering ever since if such procedure might be handled by a DIYer ,without any lab machine (as Graetzel cells are made) . Non toxic materials handled and high efficiency levels would be plus.

Topic by gabdab    |  last reply


Help! Simple but difficult way to semi stick reflective mylar to sheet metal

Wow, the whole question fit in the Topic line!  Amazing! Well, anyway, we're in the process of finalizing a design for a solar hot water heater and are still trying to figure out a good/better way to stick our mylar to our sheet metal.  The sheet is about 10 ft. (sorry about that old fashioned non-metic system usage, but we're on the U.S.-Mexican border and most of the things here in Mexico are still measured in the old system - sigh) by about 4 ft. We have used axle grease - it's o.k. but hard to spread and to make into a VERY thin film.  If the film is not thin bulges appear in the mylar since itself is only about 2 mil thick.  It was good, on the other hand, because it allowed us to position the film correctly on the metal sheet... So, this time we tried silicone - out of a spray can.  It also seems to be good, perhaps a little better since we can spread it with a small paint roller but after several days it's not holding the mylar down well enought (which is probably to be expected since we're using silicone and it's not really sticky). So, we need something which will allow us to position the film (slippery) while being a very, tiny, wee, itsy bitsy sticky in the long run.  It cannot of course be anything biodegradable - like honey - yuck - for obvious reasons (it's going to be in the sun and eventually it will, biodegrade, into who knows what). Maybe silicone and ... Elmer's glue???  We're stuck.  And, after googleing till our eyes have dropped out, we can't find any reflective mylar with a sticky backing.  What the heck do they stick on those window tinting sheets??? Anyway, any help would be greatly appreciated and of course, Have a wonderful afternoon!  :)

Topic by frazelle09    |  last reply


64 w solar panel without a charge controller or battries but using a buck converter for direct regulated power?possible?

Greetings and thanks in advance for all the help. i shall start with explaining the situation.  i am going to be in the remote himalayas for about 2 months with a expedition team and for all our charging needs  we are going to carry a few solar panels, most of them are small 5-15 watt ones . the problem comes in when i introduced the 64 w thin film roll able panel. the specifications for the panel are as follows Model PVL-64 Rated Power 64 (Watts) Rated Voltage 16.5 (Vmp) Rated Current 3.9 (Imp) Open Circuit Voltage 23.8 (Voc) Short Circuit Current 4.8 (Isc) i intend  to use 3 LM2596 ebay buck converters to get 12 volts and 2 5V USB Output Converter DC 7V-24V To 5V 3A Step-Down Buck KIS3R33S Module KIS-3R33S for usb power. All of these will have a common source of power (the solar panel) and have separate outputs as i need to charge multiple things at once.  will this setup work or i need to think of something else.?

Question by 1st rover    |  last reply


I need some PCB help

I'm trying to help a friend make a PCB for a project of his, but I've never made one myself. Using westfw's design rules in Eagle Free Edition, the board is riddled with jumpers, but there are only three with the default-width traces. I ask you, O wise Instructables community, what should I do?We were going to use the iron-on laser printer resist method, but that won't work if it is too sloppy to make thin traces. How thin can the traces be made with this method for a beginner? We also are considering using this film, in hopes that it will be a little easier to use...does anyone have experience with it?The other option that comes to mind is transferring everything to ExpressPCB instead of Eagle, in an attempt to make a bigger board that could use bigger traces.

Topic by CameronSS    |  last reply


My Epson Stylus Photo 900 printer won't recognize a refilled black ink cartridge. Does anyone know how to fix this? Answered

I put more ink into the black cartridge when it got low with a refill kit. The printer won't work and keeps flashing "black cartridge needs replacing" ! Is there a secret step I must do? The new cartridges have a thin film over the bottom ink hole, so I tried scotch taping it to simulate a new cartridge but that did not work! Help please !

Question by triumphman    |  last reply


Custom PC Keyboard protector

I'd like to make a custom fit computer keyboard protector, the type that's made to stay on while the keyboard is in use. This Ducky cover https://mechanicalkeyboards.com/shop/index.php?l=product_detail&p;=999 is very nice, but rare.  Most keyboards have no properly fitting cover available. Also, it would be awesome to say 'I did that.'   What material would be best, silicone?  What mold material? Maybe I could cover the keyboard with plastic film and spray some silicone on top?   It has to be really thin.  I'm guessing pros would use a bottom mold, then squeeze a top mold own on it. Thanks.

Topic by catsintrubles    |  last reply


expanded graphite heat-sink? Answered

Okay , I've searched and searched and cannot find what I'm looking for. Maybe the other diy'ers can help me. 1.What I'm looking for is a heat-sink made of expanded graphite or (carbon, graphite (∥) as it might be known as well) that is actually in the shape of a traditional aluminum heat-sink with the fins and NOT in the shape of thin film as it is very commonly available. I don't even know if it exists or is manufactured by any company. I've tried contacting some companies about it but they have yet to get back to me. The reason I want this is for the tremendous increase in heat conductivity as in this chart shown on this webpage http://physics.info/conduction/ . The application I am trying to use it for needs a raised, elongated surface area to displace heat semi-uniformly, hence why I need fins like a traditional heat-sink instead of the commonly available film expanded graphite online. 2. If it does exist or is able to be manufactured, would it be a ridiculously priced part or would it be a reasonable priced part? (Just doing small scale tests for now so it would be the size of a FET finned sink). 3. From what I've read it seems possible by maybe layering the films into a stacked lattice, keeping heat transfer perpendicular to the lattice, but what are your thoughts all? (I question bonding the layers myself but I don't know if you could hard press the layers together without a bonding agent since any bonding agent being used I believe would reduce the thermal conductivity quite a bit, but I'm not incredibly familiar with expanded graphite). Any and all help would be appreciated from this wonderful community Best regards, Velesh

Question by velesh    |  last reply


Homemade wax paper wrappings? Answered

Hello everyone! This is the first time I've used this feature on Instructables, so here goes. :) I'm trying to recreate vintage sweet wrappers for a friend who will use them in a film he's making for uni, and I wondered if I could somehow impregnate the wrappers in wax to make them "chocolate proof" so I could let a friend re-live times from long ago. :) I'd be using standard printer paper and inkjet ink, would this survive the waxing? Also how would I coat the paper in a layer of wax thin enough not to crack when the package is assembled? I was also planning on heat sealing the edges wsing a warmed metal tooling to first fold the paper into a tube, then crimp the edges. Thanks for any help :) (Sorry if this is in the wrong section, as its technically a wax and paper mess-afound i think it's closer to Art than anything else. :) )

Question by Llamarama    |  last reply


Electron Club Open Day Show and Tell, Glasgow 13 June

Electron Club Open Day2pm-8pm Saturday 13th June 2009Centre for Contemporary Arts (CCA), 350 Sauchiehall Street, Glasgow, G2 3JDThe Electron Club is a voluntary run space where people interested in things like free open source software, circuit bending, hardware hacking, computer recycling, streaming, audio and video editing, green technologies, and amateur radio can meet, use equipment, and share anddisseminate their skills and ideas. The space supports both individuals developing their own projects and a number of group projects, all of which are not-for-profit initiatives with a community, educational or environmental aspect to them.Now in our third year, the Electron Club Open Days are an opportunity to see and try out a range of things that people do, as well as having the opportunity to meet others with similar interests, make, chat, discuss and enjoy.TESLA SOUL - Electron Club Makers Fair and homebaking - Bajery in the Makery!Stalls and demos by electronic makers, designers and artists. An opportunity to see and play with some of the projects created by Electron Club members and related groups - a theremin menagerie and mini synthesizer kits, 3D paper engineering, circuit bending, micro FM radio,DIY wind power technology, creative computer trash recycling, 101 things to do with a dead keyboard and much more. Plus some of the excellent home-baking that has been hallmark of all our Open Days. Come and do a bit of soldering or have a cup of tea and chat with the people who make things.TAPE-WIRE-HEAD-SCREEN - music, film and sound artsThe Electron Club includes many people working in music, film and experimental arts. For the Open Day we will be showing a preview of films from Document, the UK's leading human rights film festival, with works ranging from front-line reportage to cinematic explorations of what it is to be human, along with films made at the Electron Club by the Digital Desperados, a film-group for young black and Asian women. We'll have a live performance of Alvin Lucier's legendary "Music on A Long Thin Wire" by members of 'Obscure Desire of the Bourgeoisie' and BuffalobuffalobuffaloBuffalobuffalo'. Outdoors, artist Lucie Potter will invite people on a specially planned sound walk around the Garnethill area.THE LIFE OF SOCIAL THINGS - socially-engaged technology forumA series of discussions about different ways in which society and technology come together.Glasgow FabLabsFabLabs are small scale fabrication and construction workshops that provide computerised production technologies on an artisanal scale making them available to communities and independent makers and designers. From inner-city Boston to remote Indian villages, FabLabshave become a worldwide network of community technology centres. Glasgow FabLabs is a project aiming to bring such a centre to Glasgow. This forum will present the ideas behind the Glasgow FabLabs project and explore the benefits of community-access technology.Community Media and Citizens JournalismThe internet has offered a platform for communities and groups outside of the mainstream media to have a voice and share knowledge. Whilst there are many notable examples of such activity, the tools to create such a democratized media space are still often out of people's reach.This forum will look at some practical examples of community media coming from Glasgow, present some current projects looking to make ordinary people's voices more prominent and explore the relationships between the grass-roots and mainstream media.Technology, Social Justice and the EnvironmentHow can we use technology for the greater common good? Whilst the advance of technology promotes the promise of a better world, that promise has often been compromised or undermined in how we make use of such advances. Certain technological developments have contributed to environmental and social problems on a scale arguably never seen before.Technology, however, has also been used to tackle such issues as climate change and social injustice. This forum will share and explore some practical examples being used in Scotland today, from noise monitoring devices to participatory video and community mapping projects.RAFFLE - broadband fundraiserThis year we are raising funds to improve our network facilities at the Electron Club and we will be doing a raffle with prizes including a group voucher to go paintballing.http://www.electronclub.org Contact: openday@electronclub.org

Topic by greensteam  


Electrically Conductive Plastic: a general discussion.

I find i have an odd set of interests. Specially with regards to this forum.  I'm interested in electrically conducting plastics. I've been hitting the Wikipedia pretty hard looking for information on the topic.  I've found a couple of interesting articles:  http://en.wikipedia.org/wiki/Polythiophene http://en.wikipedia.org/wiki/Polyaniline My main reason for pursuing this as of late is because I think electrically conductive plastics offer a way to create high efficiency photovoltaic cells on the cheap (least relative to growing pure Silicon crystal without oxygen contamination).  Azodyes, which are popular doping agents for current thin film photovoltaic cells  can be linked directly to the organic back bones of the polymers, and i think this will make the conversion of photons into electrons more efficient. There's other organic compounds (specifically i'm thinking of metallocenes which can be used to generate positive valences, also known as "holes" within the molecular structure of the plastics) which can be used to dope an organic solar cell, but azodyes are the most obvious. Anyway... gonna hit up google. if any y'all have ideas post em up.

Topic by Qcks    |  last reply


LED panel lights with water damage - other uses?

We had a slight roofing problem at work and as a resul a lot of our recently installed LED panel lights got flooded.Now, I though: How hard can it be to fix them....Surprisingly these flat replacements for flouroscent tubes are actually manufactured in a way that you can take them fully apart if you dare.Like some old computer or flat TV screens they use a row of LED's and then some sheets to direct and distribute the emitted evenly throughout the entire panel - like a backlight with no screen.What was a surprise however is the size of the LED's and how they are "soldered".Obviously a mass production in a reflow system.First problem for me was that the LED's used are right between two commonly used SMD sizes.So a 0204 is far to big while a 0102 won't even touch the solder pads.For once I did the smart thing and decided to try to remove at least the clearly faulty and correded bits first and did not order a bunch of LED's...A drop of glue is used to hold the LED's in place until they are soldered.But unlike any glue I encountered for this purpose the stuff won't come off.You can use proper double sided soldering tweezers or a heat gun to soften the solder but the LED itself won't come off.Last resort was to increase the temp of the soldering equippment to soften the glue or to even fully melt it.Lets just say the plastic film making the acutal connections like a circuit board does not tolerate the heat required...I have now a bunch of useless lights, some still working LED power supplies...Was wondering if anyone ever tried to make a backlight screen or one of these panel lights work in reverse?Meaning using natural light on the panel to "collect" it at the thin bit where the LED's were located.Might be useful with some fibre optics or solar cells.Are there other good uses for these films, foils and sheets in a backlight system?Don't want to toss them out only to realise a few weeks later these things are actually good for more things...

Question by Downunder35m    |  last reply


Nylon and substitutes on a cold bed

It's been some time and I made progress with Nylon. Aldi had some cheap craft glue with methanol as the solvent - this stuff works great for PLA, ABS AND Nylon. The common problem with nylon is that it has no real adhesion to anything, except cardboard and bakelite. Cardboard makes a clean up nightmare and bakelite is not always easy to find, especially not the right type. So I tried various glues, paints and primers but none was really suited for all printing needs. And the cleanup of the bed is imoprtant too as I did not want to spend hours scrubbing with acetone or similar nasty solvents. After the first great succes with the clear Aldi craft glue I checked the local 2$ shops and carft stores and found similar glueswith methanol as a solvent. Since not everyone is lucky enough to get these specials I will tell you what to look out for if you try clear craft glue: Don't buy anything that can be cleaned up with water - you want methanol or ethanol as the solvent in the glue! Do a test with the glue on something that usually does not bind well to cheap glue, like glass and blister packs. Let the glue dry and peel it off - it should be a clear film that is quite strong and barely streches when you pull it. It almost feels like hard paper. All good so far? Check if the nylon, pla or abs really sticks to it: Spread a very thin layer on a piece of cardboard and let dry. Add another, thicker layer and let dry again. Now hold it under your nozzle and extrude a bit of filament while moving the cardboard around. Let cool and check how good it sticks. In a perfect world the cool plastic should peel the papaer off with the glue. Time to prepare your print bed the same way and to start printing ;) Just use a very thin first layer and for the first layer much lower speeds than usual. I print nylon with 60mm/s and the first layer at just 25mm/s, any faster and the first layer does not look right. ABS and PLA are much more forgiving here.

Topic by Downunder35m  


Solar Filter for Telescopes

Having seen some predictions of increased solar activity over the next two years, I decided to make a filter so I can check it out with my trusty telescope. To start out, I constructed the rig shown in photo A, and practiced with it by cutting disks of plain glass. Make a table like that in photo C so you can make a continuous score on the glass, without stopping. Put oil on the wheel of the grass cutter. Be sure that the surface you work on is flat. You can skip this if you want a square filter. After scoring, your glass should look like that in photo B, with a uniform and even cut. Next, put the scored glass on a soft surface like a mouse pad, with the scored surface wetted with water and face down. Press on the back of the score with a dull nail to start a crack. By continual pressing you can watch the crack propagate all the way around. Then, make 8 radial scores from the circle to the edge of the glass and propagate those cracks in the same manner as the disk. When you do it right, you get a result like photo D, where the pieces were separated for illustration. When you get good at this with regular glass, you can cut the mirror into a disk. With the mirror, you score the glass on the side that has the metal coating. Or, you can just cut the mirror in a square instead of a circle. Photo E shows an uncut and a finished cut mirror. The mirror came out of the back of a discarded projection TV. Some of the mirrors are plastic films, some are second surface, some are first surface glass but the metal coating is too thin. There are many variations, but you need to find a first surface glass mirror that reduces the light level by 12 stops (as measured by a LunaPro SBC light meter). Photographically, this is like reducing the light level from F1.4 to F64. This level of light reduction will be hard to find. WARNING: Use of a mirror with a thin reflective coating can result in eye damage if used to view the sun through a telescope. I have access to a smaller commercial filter to use as a guide. This filter produced a bright blue image of the sun, so I added a red filter at the eyepiece. This combination produced a normal yellow image of the sun. There were no significant sunspots visible, so I didn’t bother taking any pictures. The Filter is mounted to a screw-in lens cap.

Topic by ShutterBugger    |  last reply


DIY Wallet Challenge Winners!

Congratulations to everyone who entered the DIY Wallet Challenge! The variety and creativity of the wallets were impressive- you used everything from batteries to bike tires, and produced wallets in many different shapes and sizes. The entire Instructables community judged this contest- ratings and page views as recorded this morning at 10am Pacific Time determined the winners. We appreciate your help, and realized we should modify the awards to properly represent your votes.Thus, we're giving away another category of second prize- the next three highest rated wallets will also receive Instructables Robot t-shirts! First PrizeHighest ratings. Winner receives a beta Eye-Fi Eye-Film card and an Instructables Robot t-shirt.Knobby All Terrain Rubber Wallet with Optional Smack-lights (Drop Alert Sensor) by ineluctableSecond Prize- Page ViewsGreatest page veiws. Each winner receives an Instructables Robot t-shirt.Bitchin' Innertube Wallet by jmengel(eng) YAW (Yet Another Wallet) Made from recycled stuff!!! -- (esp) Cartera hecha con material reciclado by TonyRomeroSuper Thin Tyvek Card Sleeve Wallet! by marksbrenSecond Prize- RatingNext highest ratings. Each winner receives an Instructables Robot t-shirt.Accordion-Style Card Wallet by themostbobDIY: The Magic Flip Wallet! by LasVegasThe Three Card Monte- An Origami Wallet by oscheneWe also promised stickers and an Instructables patch to five lucky people who voted in the Wallet Challenge! Thanks to everyone for voting, and congratulations to our randomly-selected prize winners: rwinferriteBubbledragonBurpy DurpystumestonAll winners should check their Private Message inbox- I'll send your prize claim information this afternoon.

Topic by canida    |  last reply


Tempered glass screen protectors - understand and beware!

I recently had the joy of needing a new screen protector for my mobile after being dumb enough to drop it on gravel. The hard cover took all the impact but the film protector on the screen was scratched badly. Was old and partially worn anyway so I decided to upgrade to a Tempered Glass screen protector. Being somewhere rural I had no chance to get one in a shop so I ordered online. With no intention of advertising for some sellers, I collected a few links so you can check what I am talking about: Item1 Item2 Item3 Item4 Item5 Item6 So, what is my concern with these? They all can be found on amazon and other online services as well as on local markets... As I said I ordered a glass screen protector. If you check these listings and even some of the packing you will notice they all have a thing in common - being shatter proof and of 9H hardness. I also love this video showing how to remove and fix a glass screen protector! The last time I checked glass had one very distinct feature: It is hard and before it really bends it breaks - unless you use fibre optics of fibre glass cloth... What is my concern and warning here? Pretty simple: Stay away from expensive scams! Some claim their screen protector is only 0.25mm thick, even the 0.2mm one I measured was over 0.5mm with the glue... The hardness of 9H refers to the so called Moh's hardness - look it up on Wikipedia if you like. That means these tempered glass protectors would have a similr hardness than a diamond, or at least close to it. Problem is that they are made from plastic to start with and not glass at all. They claims that the screen protector is flexible because it is so thin - again a fake! Even the thinnest tempered glass will shatter if you bend it enough, not so these plastic ones. If you think I am making all this up try to use a really sharp knife or deburring tool and cut the thin sides of one of these protectors. All the ones I tested could be cut quite easy - and I though glass can't be cut with a kinfe... A nice website showing that the scratch resistance is far from the claims can be found here. And a video showing how a real glass screen protector sounds and breaks can be found here. So is it really all bad and should I avoid getting one? Not really if it is only for the added protection. To be clear here, and without the intention to blame any of the above sellers, some protectors actually do have a top layer made from glass and you can hear it as in the above video - it sound solid and not like plastic if you tap it with something hard. Another factor is the simple fact that plastic absorbs impact much better than glass. So where a real glass screen protector might shatter and crack like in the above video, the fake ones might one get a nasty dint or scratch. But you should be aware and clear about what you get and what to expect from it. These glass imitations are made from a strong polycarbonate plastic, similar to the stuff used for bullet and explosion proof "glas" windows - if you every watched the Mythbusters you have seen the big sheets I mean. The top layer of these things is specially treated to repell water, oil and dirt, it also gives the surface the good scratch resistance. The technique is nothing new, camera lenses, plastic sheets and the clear covers you see over the timetable at your bus stop all use it. The new thing is to intentionally mislable a product to make the consumer think it is glass ;) What is the real difference for the user? Check this video. Here a guy performs a drop test with a real glass screen protector. Thing is once the protector breaks the screen itself is broken too but until then it was not too bad. Here it is demonstrated how a real glass screen protector reacts to certain types of abuse - one of the reason I decided on glass. Compared to the plastic counterfeits just the sound on the glass is worth it, but I think the hacksaw was best. Another video from XDA gives a bit more info on how the glass is made - if you can't seeing a phone being abused then don't watch the drop tests at the end ;) Glass with these hardness levels and types of surface protection will give the user a long and worry free use of the phone. The plastic fakes will perform at a similar level for some time but will show signs of wear long before even the top coat of the glass one fails. Both types have their uses and if the fakes would be labeled correctly the user would actually benefit from that. On bigger screens like a tablet I would actually prefer the plastic ones to prevent damage once it needs replacing. On a mobile used in less than perfect conditions I would also go for plastic as it usually is a bit thinner and will fit better within quality hard covers. But when it comes to real abuse like using with dirty fingers most of the time or mostly outdoors where a lot of dust and fine sand can be involved I always go for glass. If you paid attention to the surface treatment then you already realised that the plastic and the glass are in the same region, making them quite scratch resistant. Still fine sand or metal dust will scratch it.... The difference is in the hardness of the actual material that was covered with the oleophobic film. Glass will not give in any way, where plastic is much softer - so not to be confused with the surface hardness! This mean that sharp and point object will easier penetrate the plastic than the glass, something to be considered if you often ecounter harsh use. In terms of actual protection we need to differenciate between surface quality and actual screen damage. After all when badly scratched we can replace the protector but if the display got damaged we are back to square one. The surface hardness was already covered so let's move on to the screen itself. In some of the above videos you can see the abuse a screen might see in normal conditions, and if we would not drop our phones so often repair shops would not be at every corner LOL I have done quite a few screen repairs, mostly for friends and work mates that did not want to pay the hefty extras in a repair shop. From there I got the stories on how it happened and in almost all cases the screen cracked when the phone landed on the corners. In one case the screen and glass protector failed, including the actual display when the phone was dropped out of a 4WD and landed screen first onto a rock. A glass protector will spread the (direct onto the face) impact force onto a much larger area, where a plastic one will produce a dint onto the actual screen much sooner. So again glass wins in terms of actually protecting your expensive screen. But be aware that all this is useless if the phone lands on the corners!! Let me explain: Both the top glass on your screen and the screen protector have a thin layer of "glue". This acts like a shock absorber, so unless an impact goes deep enough so the pressure on the actual screen is too much only the protector should fail. But the screen itself is a tight fit into the frame of the phone, so all side and corner impacts go directly into the glass. As the rest of the glass has no way to give or go the stresses will crack the screen. How should I treat my phone with the new screen protector? Exactly the same way you would without it of course. But if you don't have a proper cover that offers protection of the corners you should invest in one. Having a quality protector and a good case does not mean your phone can be used as a football, see it as an added insurance in case something does go wrong. For obvious reason it can also pay off to have a spare at hand, if something bad happens that requires replacement of the protector you won't be left with an unprotected screen ;) Last but not least, double it up: For people that already know their screen will see a fair bit of abuse in term of scratches it is a good idea to put an extra film protector onto the glass one. Once it is too scratched you peel it off and replace it, while the glass protector gives you the actual protection for your screen. Corning Willow glass As time of wrinting Corning Willow glass is the only "flexible" glass on the market, unless stated with your flexible screen protector you can assume it will be just plastic. I did not list it above as this high tech material is mainly reserved for displays and at least to my knowledge is not available for screen protectors, although I will stand corrected as I have to assume some big players use it for their protectors. The material is actually a sandwich where an ultra thin sheet of glass stis bewteen two layers of durable coating, read it up on their website it is quite interesting. It won't reach the strength of their famous Gorilla glass so without an outer plastic that has the additional oleophobic coating it won't provide the strenght of real tempered glass protectors. Some phones like the Galaxy Round and the fleixble HTC phones use it for example.

Topic by Downunder35m    |  last reply


How to make a replica of The Riddler's Box (Work in progress)

All right, I admit it. I liked Batman Forever, and still do. I also liked the "Box," which was the film's signature gadget. (And no, I don't count the Batarangs--they're equipment. The Box is a gadget in the purest sense of the word.) To that end, I decided to build a replica of the Box last summer. It's still not finished--I need to work out lighting, a motor, and the lower coils. (EL wire, maybe?) By the way, I'm posting it on the forum first because it's still a work in progress. I have no Monet to buy Degas to made de Van Gogh, as it were... YOU WILL NEED: One clear 28-oz. tumbler, acrylic (I got mine from Jewel for $1 last year...I don't know if they still carry 'em) One 20-oz. tumbler, acrylic (I got mine from Walgreen's last year...ditto) Two super-size cup lids from McDonald's One large bottle of Gesso One bottle of gold paint (Antique Gold works best) One bottle of green glow-in-the-dark paint A really long paintbrush, preferably made of foam A normal paintbrush The wings are made of a piece of foam I had lying around...I need to get them made specially. It's also got some Christmas-wreath lights stuck inside, just for the picture. ------------------------------------------------------------------------------------------------------------ SO: For the 28-oz. tumbler, first you need to thin your Gesso out with water. This will allow you, later, to add the paint in such a way that light can shine through. Then, you will want to paint the INSIDE of the tumbler with Gesso, and then with the green paint. Simple as that. For the 20-oz. tumbler, you can leave the Gesso thick if you wish. Depends on your preferences, really...Then, you'll want to paint the outside of the 20-ouncer with the gold paint. With me so far? Then, you'll want to glue the two McDonald's lids together for a bit of sturdiness. I recommend Gorilla Glue for this. When that sets, you'll want to paint the outside and the inside with Gesso. The outer lid is gold in color; the inner lid is black. This prevents light from shining through the lid, which could give the game away. WINGS: As for me, I cut a pair of 11 3/4" oblong triangles from foam for the wings. They're not stable at all, but at least you get the basic idea of what it is. I stacked the 28-oz. tumbler on top of the 28-oz. tumbler, put the lids on, and stuck the wings on with tape. It's a crude mockup, but it works for now. I put the Christmas-wreath lights inside just make it look like it's doing something. I'm thinking about adding a "Fusion" light from Windy City Novelties for the finished result. The final version of this will involve some very tricky wiring--I want to wire the light-up gadget and the motor to one switch or button. If any of you have suggestions, the mailbox is open and waiting. I've very little technical experience, and would like as much input as possible from anyone who knows something.

Topic by Sharaz Destler    |  last reply


Electronic repair after a voltage spike or power surge

So far I was lucky and never got a lightning strike or other power failure to induce high voltages into my house and equippment. But over the time I got several requests from friends to take a look at things after literally all connected electronics in their house got fried. In some cases there is only a total write off as due to a lack of surge protectors inside all unwanted juice made it's way into vital components. Like a brand new Samsung TV where the replacement of the power board was the only option - which makes you wonder... But in other cases, like microwaves, induction cooktops, computers and such I had some good success with the repairs. Guess it comes down to purs luck on both sides, power surge was not too bad and simple components on the input side failed quickly enough to prevent damage to microprocessors or other sensitive parts. Right now I have an induction cooktop here again that failed after a mains transformer in street blew up during a thunderstorm. I can tell it was bad as everything in the area of fried parts has a vaporizsed metal film on the surface and not much is left that was a surge protection. I cleaned all up, replaced the varistors and missing parts of the traces on the circuit board but the cooktop is not performing the way it should anymore :( At some stage during cooking it turns off with a meaningless error code stating the input voltage was out of bounds. So my next attempt was to literally remove every single component from the filter and power supply board to measure for any possible connections between the traces. By doing so I noticed several points where I had a quite high but measurable resistance in areas where there should be none. Mostly on the direct input side where the varistors tried to save things. So I used my Dremel in a tin drill press to cut the circuit board aourd the affect areas (where possible with a drill, otherwise with a thin grinding disk).. Sure enough I was greeted by charcoal colored dust in several areas. After removing all material until the dust was "clean"  tried again and this time all seems to work fine. I would like to use this topic to offer some help and guidance in case you have devices that suffered a severe power surge of some sort. Many of us either have no insurance to replace those items or even if you do the device might be expensive enough to try a repair despite getting it replaced. Trust me, even it went up in smoke there is still a chance to fix it in some cases and if proper protective circuits were in place the repair could as cheap as a few Dollars for replacement parts. To get useful advice the following things should be included in your request: Some clear pictures showing a close up of the affected parts - if there is visibale damage to be seen. A brief description of what happened, e.g.: lightning strike directly into the house or outside power lines, generator or inverter failure or simply that the power company stuffed up and your entire street was affected. Of course you will need the means to take the device apart for investigation and also some basic soldering skills or somehow how has and can assist you. But if you are up to the challange I am willing to help if possible.

Topic by Downunder35m    |  last reply


Cloning the famous ARA-2000 antenna for SDR use

Several years ago the company behind the original ARA-2000 antenna, Dressler Hochfrequenztechnik, closed.The ARA series of antennas, like many other products by this company never got a patent, instead it was trusted that no one would bother to replicate it.A bit like the Swiss Army knife, many tried to copy it, none really managed to match the original quality.There is quite a bit of hacking still going on for this antenna, most projects though seem to be abandoned at the time of writing this.I am currently trying to figure out how to create an entire clone that everyone who knows how to properly use a soldering iron can build.There is a lot to consider here...The active element is of quite unusual shape and needs to be wound around a cylinder of a pretty accurate diameter.My initial tests showed that for example aluminium foil with some unavoidable wrinkles already has a negative effect.And a change in diameter of just 2mm means the entire antenna only performs badly for the entire band.This part is thankfully already solved to my satisfaction using thin copper sheets and some stiff plastic sheet.Quite a pain though is the MMIC part - the amplifier that makes the antenna active.There is a ton of MMIC blobs available, either solo or as a ready to go amplifier.Downside is that without really knowing any characteristics of the original is comes down to guesswork.And as most of the cheap SDR dongles won't provide a BIAS TEE I will opt for an external power supply for the amp.I might provide the option for a inline use a bit later though.Why clone the ARA-2000 antenna?For starters you need to forget the mythical stories you might have heard about this antenna."Picks up even the weakest signals!", "Totally linear over the entire bandwidth" and so on...Without the amplifier the antenna is actually not even average in therms of reception performance.My initial tests with a network analyser showed that the anteanna actually is behaving really weird (without the amp!).Although this first bit needs further testing, it seems that most, if not all of the work in the 1.5-2GHz range is done by just the straight connecting strup going from the amp, or in my test case the coax, to the wrapped antenna part.For anything in the more interesting frequency bands it seems that the antenna is not using anything like a discone, whip or ground plane antenna.Instead the 3rd harmonics of a given frequency provide the max power output from the antenna but it arrives at the cable at the right frequency.Especially in the lower frequencies, below 200MHz there is also quite some phase shifting happening.As a passive antenna it seems to be almost impossible to find a frequency to transmit on without using some matching trickery first.But when it comes to size or looks, the ARA outperforms everything you can think of unless you want to constantly adjust the length of your whip antenna.And if you check what is available in real (user) data in terms of noise and signal quality than most other antenna types are far worse.The design provides a wide frequency range with very little noise, almost like a build in filter.Considering that mostly harmonic frequencies are used not that surprising.Getting hooked on SDR means you start little and then you want more and more.Unless you really need the low frequency HAM bands below 50MHz the ARA is a good choice that just makes sense.What is quite surprising in the original is the total lack of protection for strong signals.Sure, we might never need a lightning arrestor because all is enclosed in plastic and has little attraction lightning, but someone hittiing the transmit button close by....I will have to do some more checks to determine whether or not more protection is required.What is the problem with amplifier?For starters, no one really knows what was used in the original - they all just guess based on how well the real design matches some datasheet.Means whatever was used might as well be a custom made solution.I checked a few datasheets for MMIC amps but could not find any useful reference to the handling of things like negative gain, phase shift or a constantly changing impedance.Some however state that a 50 or 75Ohm signal is provided at the output.If I interpret that correctly than those MMIC's not only amplify but also do some matching.In most cases you won't need an amp that works outside what the antenna can provide.Problem is that I don't like regretting things later on ;)So IMHO it would be best to use a wideband MMIC covering all from about 1MHz to a few GHz.Additional filters can then cut off what is not required or where the antenna starts to fail.What is clear by the original design is that the cable shield acts as a ground and most likely also has a balancing function.It would make sense to add a ferrite trap close the the receiver to filter out what the cable might otherwise mess up.Can the frequency range be lowered to get even the low HAM bands?The answer is YES and NO.It is not a big problem to extend the cone shape and then hope to come much lower.Issue with this is the helical, long periodic design.As basically only the 3rd harmonics are used for all interesting frequencies any ARA type antenna going much lower would end to be really long.You can't just make it longer!One thing is to have a full and even number of turns.The original only had two, three turns is bad, four means the entire antenna is slightly longer than your average downpipe for your roof gutters....Other, seemingly logical alternative would be to stick to two turns and to increase the diameter.Apart from the size problem here we would also change the shape of the foil quite a bit and I have not done enough tests with that to provide a conclusion.Are there alternative design options?As it turns out copper pipe is available in 80mm diameters for the use in chimneys as well as downpipes.With a proper machine it would be pretty straight forward to remove what is not used as the active element.Milling a pipe or rod is these days a common thing in many good workshops.But on a hobby level and low budget....One of the best options for cheap test antennas of this design is to use tinting foil - the cheapest you can find ;)Just read the lable and make sure it does not use a metalised film.If it has no UV protection and no tinit at all it is best but hard to find.A little less stiff is the stuff to cover school books or cupboards.Vinyl is bad though!If you look for copper foil in the cheap online places you mostly find the suff used for shielding in rolls of 200x1000mm.Unless you have a really sharp knife or really suitable sissors this stuff is a pain to cut as the glue tends to stick very good to whatever you use to cut through.Don't ever try one of these blade type cutters for paper and pictures unless you put a slight oil film on all cutting surfaces first....In some hobby shops you can get copper foil without any glue in different thicknesses - this stuff is the prefered option.Not only cheaper than the China rolls with glue but you invest a bit more and get a thickness that does not wrinkle right away when working with it ;)Cheap, steel downpipe and cutters or nibblers?I though about and I tried - and I failed LOLUnless you use a pin type nibbler and custom made rig the result is quite bad - at least mine was.What works though is to use thin aluminium sheets, cut them and then bend them around a suitable template.But I ran out of old laminated sings to salvage and the duble sided ones I have left are too much work.What comes next?Well, I have a few rolls of copper sheets coming next month, the cheap glue covered type.This time however I will leave the plastic cover on and use tape to secure the foil to the pipe.A two-stage amp with external power supply is coming too so I can do some more tests in this area.For the time being I will opt for some 3D printed end caps but with a bit of luck can find something easier next time I have time to waste in the hardware store.Excluding cable and a cheap USB or 12V power supply, the current costs of building the anteanna are around $40US.About half of that if you don't cennectors and attach the coax directly.Another experiement I am working on is to use copper tape, 12mm wide, to create the antenna in a semi-fractal style.I am hoping this will provide a high enough gain so the antenna is usable without an amplifier.Right now the biggest issue is to find a really SDR suitable way to deal with strong signal close by.I will keep you update here when I start with the new antenna and upload some pics along the was of building it.

Topic by Downunder35m    |  last reply


The Memristor - they've found it!

This came out quite a few days ago, but I haven't seen it until today.HP's Henry Williams and his group have accidentally stumbled upon the fourth fundamental element in electronics - the memory resistor, or memristor. Basically, it's a resistor that changes its resistance with elapsed current flow, or total amount of charge that has passed through it, and retains its resistance even after current ceases to flow through it. From the article:"The classic analogy for a resistor is a pipe through which water (electricity) runs. The width of the pipe is analogous to the resistance of the flow of current—the narrower the pipe, the greater the resistance. Normal resistors have an unchanging pipe size. A memristor, on the other hand, changes with the amount of water that gets pushed through. If you push water through the pipe in one direction, the pipe gets larger (less resistive). If you push the water in the other direction, the pipe gets smaller (more resistive). And the memristor remembers. When the water flow is turned off, the pipe size does not change.Such a mechanism could technically be replicated using transistors and capacitors, but, Williams says, “it takes a lot of transistors and capacitors to do the job of a single memristor.”The memristor's memory has consequences: the reason computers have to be rebooted every time they are turned on is that their logic circuits are incapable of holding their bits after the power is shut off. But because a memristor can remember voltages, a memristor-driven computer would arguably never need a reboot. “You could leave all your Word files and spreadsheets open, turn off your computer, and go get a cup of coffee or go on vacation for two weeks,” says Williams. “When you come back, you turn on your computer and everything is instantly on the screen exactly the way you left it. "Apparently, evidence of memristors has been around for quite a while, but it was only until now, during the age of nano-technological exploration, that we finally have labeled the "strange voltages" we've found in experimental circuits as a result of memristor behavior. The discovery was made while doping Titanium dioxide with some dopant that the article fails to cover. Anyhow, the resistance of TiO2 changes with the amount of dopant covering it. Since the dopant does not adhere perfectly to the TiO2 substrate, the flow of charges (electrons) can move the dopant, and cause it to cover more or less of the substrate, thus changing its resistance. "Williams found an ideal memristor in titanium dioxide—the stuff of white paint and sunscreen. Like silicon, titanium dioxide (TiO2) is a semiconductor, and in its pure state it is highly resistive. However, it can be doped with other elements to make it very conductive. In TiO2, the dopants don't stay stationary in a high electric field; they tend to drift in the direction of the current. Such mobility is poison to a transistor, but it turns out that's exactly what makes a memristor work. Putting a bias voltage across a thin film of TiO2 semiconductor that has dopants only on one side causes them to move into the pure TiO2 on the other side and thus lowers the resistance. Running current in the other direction will then push the dopants back into place, increasing the TiO2's resistance.HP Labs is now working out how to manufacture memristors from TiO2 and other materials and figuring out the physics behind them. They also have a circuit group working out how to integrate memristors and silicon circuits on the same chip. The HP group has a hybrid silicon CMOS memristor chip “sitting on a chip tester in our lab right now,” says Williams."I think this is pretty awesome, considering the current breakthroughs in nanotechnology and downsizing of transistors, memristors would enable a whole new field to be born, and circuit theory may have to be re-designed.Like Leon Chua said, the man who first came up with the idea of a memristor, "now all the EE textbooks need to be changed."These next few years in the field of EE should be very interesting =)Image from Spectrum Online

Topic by T3h_Muffinator    |  last reply