resistr app - A beautiful, easy to use, resistor color code calculator - Page 1
Forum section: electronics / projects

author: nadavt
author_rank: Newbie
timestamp: July 12, 2014, 08:02:30 am
content: Hi There!As an avid maker and EE student, I often find myself trying to decipher some color code on some obscure resistor or maybe needing to know the colors of a certain resistor value.Trying to use those resistor tables or awful online calculators just isn't fun or efficient. Also, as a person that admire product and graphic design, I was often thinking that there must be another way - not the 'engineering' way, of laying out ALL the information for you to take, but a more subtle approach that would help beginners and won't overwhelm them unlike other apps on the market.Thats why i've came up with the idea of 'resistr'. It took me almost two months (and all of my free time) to design, build and test the app - trying to keep it simple but not underpowered.The result is a gorgeous app with a simple and fun user interface, that hopefully every EE student or amateur will be hooked instantly.I'm currently in the final stages of testing the app and uploading to the iPhone AppStore. I've began developing the Android version as well, which I hope will be available in the next couple of months.resistr is now available! visit our site athttp://resistr.coor search the AppStore to download.

author: cs.dk
author_rank: Unknown
timestamp: July 12, 2014, 09:23:22 am
content: An app i find really helpful is Electro Droid. It does resistor color codes + all sort of other calculations. Really handy.https://play.google.com/store/apps/details?id=it.android.demi.elettronica

author: robimarko
author_rank: Regular Contributor
timestamp: July 12, 2014, 09:28:25 am
content: Yeah I use electrodroid daily,but this app has really beautiful design

author: bwat
author_rank: Frequent Contributor
timestamp: July 12, 2014, 09:29:55 am
content: Sorry but I just had to say the following as it seems you're quite serious about this and not viewing it as a little project. I hope you can accept it in the spirit of constructive criticism in which it is offered.Quote from: nadavt on July 12, 2014, 08:02:30 amTo be honest, I think you're trying to find a problem for your solution.As someone who is not colourblind and has fairly decent vision, it seems like you've taken a problem that can be solved very quickly with a piece of card with a chart printed on it (that was actually part of the packaging of the box of resistors you bought so you cut it out for future reference) and built a slower solution that requires a microprocessor and manual input. You've added new steps to an old process giving the same result.Consider this quote:Quote from: Alan PerlisIf your software isn't pushing the "clerks" into the realms of "higher thought", then maybe you're not using your programming skills to build the most interesting things. You've only got so many keystrokes in you so use them wisely.

author: cellularmitosis
author_rank: Unknown
timestamp: July 12, 2014, 09:30:25 am
content: Looking forward to it!

author: josem
author_rank: Regular Contributor
timestamp: July 12, 2014, 09:33:32 am
content: Looks good thanks.Another good resistor app is ResistorVision which I use to decipher resistor values by simply pointing my iPhone camera at them:http://resistorvision.com

author: tszaboo
author_rank: Super Contributor
timestamp: July 12, 2014, 09:33:55 am
content: And does it have 4 or 5 color resistor calculators? Or EIA SMD calculator? Or tolerance? Where is the windows phone version? Why is this better than a paper hanged on the wall of the hobby corner?

author: nadavt
author_rank: Newbie
timestamp: July 12, 2014, 10:01:48 am
content: Thanks everyone for your comments!I can certainly relate to the comments about the usage of resistor tables and cards and I've used them myself many time through the years.While not trying to say that my solution is the most efficient one of all, I do think that there could be a solution which is more enticing and less intimidating for use with people that are not used to reading or using more technical engineering tools.By making an this app, I think that students and hobbyist would find it useful and more accessible to use than plain resistor tables.Regarding 4 and 5 stripes resistors - After the first version will be approved, I will try to incorporate more features like that and have them available in a future software update. Just need to design and think how to do it easily as to not miss the main purpose of the app.Hope I made my vision clearThanks again all!

author: AndyC_772
author_rank: Super Contributor
timestamp: July 12, 2014, 10:14:24 am
content: Is decoding resistor values really that intimidating compared to whatever piece of design actually requires someone to work out a resistor value?I'm all for keeping things nice and simple, but the hardest part of decoding resistors is seeing what the colours are on a tiny part, and reliably telling the difference between them. And there really is no shame in testing a resistor with a meter, however unfashionable some people (who, in my experience, are *never* actually design engineers themselves) may think it is.If you actually want to use the colour codes, then learn the sequence. Black, brown, red, orange, yellow, green, blue, violet, grey, white. It's really not that hard.I'm afraid I think your two months' worth of free time would have been much better spent learning, say, how to use an FPGA or an ARM based microcontroller if you can't already.

author: onlooker
author_rank: Frequent Contributor
timestamp: July 12, 2014, 12:12:48 pm
content: Yes, something likehttp://resistorvision.comis more interesting for the developer and the user.It would be even better if someone can come up with an app that can do full fledged pattern recognition for all resistors on a board from a picture and place a little text box near each of them in a smart way.

author: nadavt
author_rank: Newbie
timestamp: July 12, 2014, 12:29:07 pm
content: Quote from: AndyC_772 on July 12, 2014, 10:14:24 amThe way I see it is that this app might help welcome new students and hobbyist into the electronics field, using a design language that they already understand and feel comfortable with it.Although this app only tries to solve one hassle amidst the vast range of problems that the average student has to deal with, if it does that well enough - I certainly won't consider my time to be wasted on learning new skills such as iOS and Android development.Personally, I think that software development skills are not less important for an engineer these days than learning a new ARM micro...Thanks.

author: c4757p
author_rank: Super Contributor
timestamp: July 12, 2014, 12:38:40 pm
content: People don't just memorize this?

author: amyk
author_rank: Super Contributor
timestamp: July 12, 2014, 12:40:51 pm
content: Two months to make a GUI with some pretty buttons... I hope that includes the time you spent to learn app development. Not bad if it's one of your first apps but I agree with the others here that its usefulness is limited. There are tons of these calculators out there already.Besides the fact that the resistor colours are one of the first things one should memorise when beginning electronics, the increasing popularity of SMD also makes this less relevant...

author: aroby
author_rank: Regular Contributor
timestamp: July 12, 2014, 12:45:48 pm
content: Quote from: josem on July 12, 2014, 09:33:32 amA shame that's not on Android.

author: Stonent
author_rank: Super Contributor
timestamp: July 12, 2014, 01:21:29 pm
content: Quote from: c4757p on July 12, 2014, 12:38:40 pmWell some of us have other professions.

author: tautech
author_rank: Super Contributor
timestamp: July 12, 2014, 02:12:01 pm
content: Black, Brown, Red, Orange, Yellow, Green, Blue, Purple, Grey, White.Didn't even look at a chart, and for me it's a hobby.Really how hard is it?

author: SeanB
author_rank: Super Contributor
timestamp: July 12, 2014, 02:22:46 pm
content: Try remembering that along with the telephone cable colouring system. It works well, even if the colour orders are different, and they call the grey coloured wires slate. But you do find a lot of white and red wires there though.https://en.wikipedia.org/wiki/25-pair_color_code

author: rob77
author_rank: Super Contributor
timestamp: July 12, 2014, 02:29:40 pm
content: actually it's pretty easy to learn "reading" the resistor values directly from color code. i don't even think about the colors i see - i "read" the value directly. it's like learning an extremely simple language

author: VK5RC
author_rank: Unknown
timestamp: July 12, 2014, 02:34:19 pm
content: Black Bull Ran Over Your Garden Blue Pansies Gone West, works for me, esp past yellow, I never seem to forget 0—4., to me the biggest problem is who came out with the idea of a blue background, cream was a lot easier.

author: tautech
author_rank: Super Contributor
timestamp: July 12, 2014, 03:04:51 pm
content: QuoteWhat about the backgrounds of: bright green, red, dark brown, purple and fawn, not to mention the 3 shades of green, 3 of cream, and at least 3 of blue.And that assortment is in my resistor trays.Whats more I've seen yellow instead of gold and gold instead of yellow.Now how will one write the software for imagery to sort that mess out and identify the values correctly?Learn and remember the colors and you have them for life.

author: eneuro
author_rank: Super Contributor
timestamp: July 12, 2014, 03:24:03 pm
content: There are good tricks for memory improvements

author: bwat
author_rank: Frequent Contributor
timestamp: July 12, 2014, 03:51:33 pm
content: Quote from: nadavt on July 12, 2014, 12:29:07 pm1) "design language" - garbage! Read Mitchell's "The Logic of Architecture"http://www.amazon.com/The-Logic-Architecture-Computation-Cognition/dp/0262631164for a way to express design in a formal language - not some airy fairy nonsense but first order predicate logic. That book is the best intro to logic I've ever read.2) You're making things difficult for beginners. Apps like yours help beginners become good at being beginners. It doesn't help them make to move on towards competence and expertise.Quote from: nadavt on July 12, 2014, 12:29:07 pmI qualified my comments with the observation that this was not a little project because I think little projects are very important. I've written many many lines of code which were written as a proof of concept or just because I thought it would be nice to be using my own programming language compiler/cryptographic algorithm/operating system/etc. Mind you I would never lower myself to the level of writing an app - I'm a serious programmer don't you know!

author: Stonent
author_rank: Super Contributor
timestamp: July 12, 2014, 05:48:32 pm
content: Green-white, green, orange-white, blue, blue-white, orange, brown-white, brown.That's currently holding the place in my memory where resistor codes would have been.

author: rob77
author_rank: Super Contributor
timestamp: July 12, 2014, 06:14:36 pm
content: Quote from: Stonent on July 12, 2014, 05:48:32 pmactually it's better to remember the pairs 1,2 - 3,6 - 4,5 - 7,8 and then associate the colors orange, green, blue, brown - and you know the wiring for both standards - just remember orange and green pairs swaps for the other oneand this way you remember the cross cable wiring as well - just swap the pairs on one endfurthermore if you know which pairs are used for what technology - you know the wiring for all of thosefast etherne 1st + 2nd pairgig ethernet - all of themISDN 2nd & 3rd pairPOTS - 3rd pair

author: Stonent
author_rank: Super Contributor
timestamp: July 12, 2014, 06:21:20 pm
content: Quote from: rob77 on July 12, 2014, 06:14:36 pmYeah and some previous guy where I worked decided since 100BaseTX only needed 4 wires, he split pairs and in some places have 2 ports on one cable. All of that's going to have to go since we're getting a new VOIP phone system that wants Gig and POE.

author: tszaboo
author_rank: Super Contributor
timestamp: July 12, 2014, 09:19:58 pm
content: Quote from: c4757p on July 12, 2014, 12:38:40 pmWell it is not like we use TH resistors anymore. But to be fair, last week I worked with some melf resistors, those have stripe also.

author: rob77
author_rank: Super Contributor
timestamp: July 12, 2014, 09:32:08 pm
content: Quote from: NANDBlog on July 12, 2014, 09:19:58 pmactually i'm using THT components quite often during proof of concept on a breadboard and prototyping on a protoboard, and i think there are more of us hobbyists doing it that wayi don't like simulations - i rather "eye-ball" the values and adjust during proof-of-concept phase on a breadboard. for many ICs i have to make adapter boards (nonexistent or unavailable in DIP), but luckilly resistors and capacitors are still available and will be available in THT for a long time yet. therefore the ability of reading the color stripes directly is still a desirable skill among us hobbyists

author: MisterDiodes
author_rank: Frequent Contributor
timestamp: July 13, 2014, 03:13:21 am
content: You probably don't need an app for resistor color codes (even if you still use TH parts)...Just resort to some mnemonic poetry to help you remember the color order.One of the cleaner versions I learned is: Bad Booze Rots Our Young Guts But Vodka Goes Well.It goes downhill from there into various versions that can't be used in a public forum.

author: MisterDiodes
author_rank: Frequent Contributor
timestamp: July 13, 2014, 03:24:08 am
content: Sheesh - I should have just looked here:http://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics

author: rs20
author_rank: Super Contributor
timestamp: July 13, 2014, 03:33:43 am
content: My concern would be that anyone using this app is actually insulated from the (relative) elegance and memorability of the system. Making little helper devices that hide away little difficulties encourages fear and apprehension about what's really going on. Does this attract people to electronic engineering, or does it attract people to Resistr while making themfearfulof electronic engineering?"OK, I'm going to try to memorise this. So if the third band is orange, you put the decimal point after the second band... and the answer is in kiloohms... but only if this is a 3-band resistor. If it's 4-bands, you put the decimal point after the third..."No. Orange means 3. Always. In this case, 3 zeros. Done.

author: Dagon
author_rank: Regular Contributor
timestamp: July 13, 2014, 07:40:44 am
content: You guys have some complicated systems. Personally I have to use my limited brain power for other things. If I have an unknown resistor I just stick a multmeter across it.QuoteMatrix style "I don't even see the code", I like it

author: rob77
author_rank: Super Contributor
timestamp: July 13, 2014, 08:29:53 am
content: Quote from: Dagon on July 13, 2014, 07:40:44 amactually it's pretty natural to the human brainit's very similar to learning Morse code - you don't listen to dots and dashes , you listen to letters and numbers - your brain does the translation

author: David_AVD
author_rank: Super Contributor
timestamp: July 13, 2014, 08:58:34 am
content: Reading resistor colour codes is an easily learnt skill for people with normal colour vision. I learnt when I was about 10 years old. It's just not that hard to do.Relying on a meter can land you in trouble when repairing equipment. Being able to scan a PCB for low value resistors (that are more likely to be damaged) can really speed up the diagnostic process.Reading the values becomes second nature and you don't really have to think about it. You just see the values almost instantly.

author: Neganur
author_rank: Unknown
timestamp: July 13, 2014, 04:01:04 pm
content: How about you make your app help learn the colour code, what will those poor students do when their phones are out of battery.I would think that this is probably one of the most beneficial things to learn in a proper way instead of just learning some rhyme by heart (i.e. Big boys race our young girls ...)I forgot the exact words I used when I learned the numbers many years ago but it was something like this:a black hole holds zeroone brown chairtwo red lipsthree orange orangesfour yellow lemonsfive green leavessix blue wallsseven purple violetseight grey octopus armsnine white micetranslated from Danish, so that's why it's orange oranges (orange appelsiner) but maybe you get the idea and can find better native English mnemonic.

author: echen1024
author_rank: Super Contributor
timestamp: July 13, 2014, 06:58:50 pm
content: I use Agilent Elec. handbook which ahs resistor colors, capacitor codes, logic simulation, AD conversion simulator, and a resistive divider solver. I find myself using the cap codes frequently, as I have memorized resistor colors and the resistive divider.

author: Rufus
author_rank: Super Contributor
timestamp: July 13, 2014, 09:39:24 pm
content: Quote from: David_AVD on July 13, 2014, 08:58:34 amMemorizing resistors in the E6 range gives you 9 of 10 colors.

author: Pack34
author_rank: Frequent Contributor
timestamp: July 13, 2014, 09:47:16 pm
content: Why not just use a meter? I rarely use through hole resistors, but when I do I just grab them out of their bin/bag, verify with a meter and install.

author: SirNick
author_rank: Frequent Contributor
timestamp: July 13, 2014, 11:29:45 pm
content: I confess that I haven't memorized a lot of the stuff that I should to be a "serious" hobbyist. I probably would've given in and practiced the color codes if I could reliably tell all the colors apart, but I mostly use those mini, 1%, 1/4W TH resistors. The tiny and sometimes badly printed markings on a blue background can make red, orange, and brown look almost identical. If I haven't just pulled it from organized trays of new parts, I'll almost always meter it anyway, just to be sure. Not to mention the number of times I couldn't tell if the brown stripe was supposed to mean "1xxx ohms" or "1% tolerance".As far as app-based references, I use Resistor Calculator and Circuit Playground. Resistor Calculator is lightweight and loads fast, while CP has a lot of other handy features (calculators and pinout references) so I'll use that instead if I have other things to look up. I would not bother to download this one though.OP -- here are the reasons why I would pass over your app in the App Store. This is only meant to be constructive criticism:1) It doesn't do enough to be useful. If I'm going to take the time (...) to pull out my phone and load an app, it should at least cover all the resistor types I use. Sure, I have some of 3-band resistors, but not many. Most of them are four bands.2) If I'm going to bother with an app, color codes needs to be but one of its handful of useful purposes. Other handy things: Series-parallel calculators, cap codes (104, etc., preferably with the alpha codes as well), temp-co (C0G, X7R) reference, etc. Also, consider having a value-to-color mode as well.3) Convenience is the number one concern. Balance features and looks with load time. If it's a bloated beast of an app, I'll download something faster instead. I care a lot less about it being beautiful, and a lot more about it being fast and easy to navigate. If I'm using the app, I'm probably trying to verify a part -- not in the mood to fawn over UI aesthetic. You're making the mistake of thinking your pride distinguishes your product. Your users will not share your priorities. Keep that in mind. It's a common trap for engineers of any persuasion, from PCB design to code to architecture.

author: andyturk
author_rank: Frequent Contributor
timestamp: July 13, 2014, 11:35:15 pm
content: Quote from: Neganur on July 13, 2014, 04:01:04 pmBad Boys Rape Our Young Girls But Violet Gives Willingly.Learned that in the Boy Scouts(tm).

author: N2IXK
author_rank: Frequent Contributor
timestamp: July 13, 2014, 11:56:47 pm
content: Bad Beer Rots Our Young Guts, But Vodka Goes Well.....

author: David_AVD
author_rank: Super Contributor
timestamp: July 14, 2014, 12:07:43 am
content: I simply learned the colour sequence. No mnemonics required.

author: eneuro
author_rank: Super Contributor
timestamp: July 14, 2014, 07:53:31 pm
content: Quote from: David_AVD on July 13, 2014, 08:58:34 amRelaying on color resitor codes when repairing PCBs can sometimes lead to huge mistakes if it was overheated and its oryginal colors... changed while it was close to explodeImpedance meter with <0.6V test voltage in pulse can be more usefull than any touching those small "smart" phones screens.These devices are useless and I prefere normal old classic phone with call/cancel button.If you know where to find smalest one @ classic hand clock size without any android or worse window$ let me know

author: Rigby
author_rank: Super Contributor
timestamp: July 14, 2014, 07:55:24 pm
content: Quote from: c4757p on July 12, 2014, 12:38:40 pmAgreed. Black, Brown, the rainbow = 0, 1, 2-9. Not sure what's so hard about it.Well done on the app, though. Seriously.edit: this reminds me of the time I was in HS, and our brand new LaserJet III arrived. It had a HPL reference booklet that came with it. I fiddled with that for a while and was printing all kinds of neat stuff, using up all the toner & getting in trouble.I decided that it would be easier to write a .bat file to print a cheat sheet small enough to tape to my thumbnail than it would be to actually memorize the material for one of my classes, but our DOS environment was such that I couldn't save the .bat file while I was working on it. No floppies, no hard drives, and for some reason that I can't remember, I was unable to edit the program after I entered it. I had to reenter the entire thing each iteration.Well I wound up re-typing the cheat sheet so many times that I memorized everything on it before I had debugged the .bat file fully.That's what this app feels like, to me. I learned a hell of a lot about HPL and DOS escape sequences, AND I learned all the stuff I could fit onto that tiny bit of paper (which was a lot.)

author: bwat
author_rank: Frequent Contributor
timestamp: July 14, 2014, 08:07:00 pm
content: Any mnemonic is only of use to us who don't have to read the code every day. The colours are no different to the digits. If you can use digits in scientific notation without mnemonics then your brain could do the same with colours. I have no problem believing there's people reading this who don't even "think" of the colours they just see the numbers.Technically "10e2" and "Brown Black Red" are both representations of the same number. If you think "10e2" or "1000" are numbers then you're so used to using the digits that you've confused the number and its representation. There's no difference between them, they're both learned representations.

author: SirNick
author_rank: Frequent Contributor
timestamp: July 14, 2014, 08:20:29 pm
content: ... if you use them every day. Alternatively, if you've used them for 30 years. There are many of us who build things on the weekends, and may need to identify a few resistors by color code maaaaaybe once a month on average. As SMD gets more accessible, then it's only useful when prototyping on breadboard.Add to that the plethora of things the hobbyist will need (want) to know: C, fuse settings, crystal frequencies, CLI commands, pinouts, part numbers, so on and so forth.That's what's "so hard about it."Not actually hard, just not something that's constantly on the forefront for some folks.

author: grumpydoc
author_rank: Super Contributor
timestamp: July 14, 2014, 09:01:31 pm
content: Youdohave to be careful these days what mnemonics you teach - otherwise you could land inhot waterI confess to having learnt that particular rhyme when I learnt the colour code, albeit with a slightly more pejorative word for the 2nd "B".I'll stick to Black Beetles Running On Your Garden Bring Very Good Weather, for now,.... maybeThe difficulty I have these days is that red, orange and brown seem to have become indistinguishable.

author: free_electron
author_rank: Super Contributor
timestamp: July 14, 2014, 09:21:58 pm
content: here's a thought : why not make a simply app that uses the camera to snap a picture and tells you what value the damn thing is ?i am color blind. i have no clue if i am looking at a 1k1, a1k2 or a 1k5 resistor.camera's are not color blind.anyway the point is moot. i only use surface mounted parts

author: grumpydoc
author_rank: Super Contributor
timestamp: July 14, 2014, 09:51:45 pm
content: QuoteSomebody already did - there was a link earlier in the thread.Being colour blind is a perfectly good excuse for not bothering but it's not exactly hard to learn and use otherwise.

author: ampdoctor
author_rank: Frequent Contributor
timestamp: July 14, 2014, 10:25:55 pm
content: Quote from: andyturk on July 13, 2014, 11:35:15 pmAs coarse as that is, it's still a sanitized version of the original which is politically incorrect and racist beyond words. They changed the first word so I'll let you figure it out on your own.But yeah, once you've heard that mnemonic you won't easily forget it, and within a very short period of time it becomes automatic and you won't need it or a calculator. As previous posters have already pointed out, color codes are becoming less relevant by the day.

author: cellularmitosis
author_rank: Unknown
timestamp: July 14, 2014, 11:11:25 pm
content: Quote from: AndyC_772 on July 12, 2014, 10:14:24 amIt depends upon what his goals are. Having a self-developed cross-platform app which has made it into Apple's App Store is enough of a resume to guarantee a position at an app development shop. With sufficient hard work, he is then just 5 years away from making $100k+. Certainly not a waste of time if that is his goal.

author: cellularmitosis
author_rank: Unknown
timestamp: July 14, 2014, 11:14:42 pm
content: Quote from: NANDBlog on July 12, 2014, 09:19:58 pmI guess I'm not "we"

author: cellularmitosis
author_rank: Unknown
timestamp: July 14, 2014, 11:17:21 pm
content: Quote from: Dagon on July 13, 2014, 07:40:44 amand I just look at my desktop wallpaper

author: Thor-Arne
author_rank: Unknown
timestamp: July 15, 2014, 12:27:21 am
content: Quote from: cellularmitosis on July 14, 2014, 11:17:21 pm

author: Rigby
author_rank: Super Contributor
timestamp: July 15, 2014, 02:12:28 am
content: Quote from: AndyC_772 on July 12, 2014, 10:14:24 amNope, nope, no, no way, disagree disagree disagree.... well, maybe.If you're saying that the time was wasted, I vehemently disagree with that. Clearly the chap has an interest in software, and this was valuable real-world software design experience that (IMHO) was time well spent.If you're saying that he should have spent that time on electronics when his at-the-moment interest was in software development, I disagree with you.If you're saying anything else, I don't really have an opinion yet.The thing about doing things the hard way is that you can learn a heck of a lot doing it. The longer route is the longer route but there's more knowledge you don't already possess littered along the longer route, and you won't ever get that knowledge by taking the shorter, easier route.

author: rob77
author_rank: Super Contributor
timestamp: July 15, 2014, 06:06:59 am
content: Quote from: Rigby on July 15, 2014, 02:12:28 am

author: AndyC_772
author_rank: Super Contributor
timestamp: July 15, 2014, 06:59:01 am
content: I guess it depends how you view the time spent on developing this app.Time spent learning a language, OS, development environment and UI design skills, with a view to re-using these in app development == good commercial skills and time well spent.Time spent over-engineering a very basic tool that's already been done many times before and which potential users will very quickly grow out of needing at all == misguided, IMHO.

author: pickle9000
author_rank: Super Contributor
timestamp: July 15, 2014, 07:21:45 am
content: Quote from: free_electron on July 14, 2014, 09:21:58 pmOr better yet take a picture of a chip / device and have it come up with a datasheet.

author: tautech
author_rank: Super Contributor
timestamp: July 15, 2014, 07:50:07 am
content: Quote from: pickle9000 on July 15, 2014, 07:21:45 am+1

author: TerraHertz
author_rank: Super Contributor
timestamp: July 15, 2014, 02:28:02 pm
content: Two months to write a smartphone App, to avoid spending one day (maximum) learning a simple color-to-number code.Having memorized that it will always be with you. No flat batteries, getting lost or stolen, maybe incompatible future versions, etc.How far we have advanced! /sarcasm.Next, write yourself an App to recall the E12 values. Because who has time to memorize that shit, right?10 12 15 18 22 27 33 39 47 56 68 92Have to confess I never bothered learning the E24 and higher sequences:http://www.logwell.com/tech/components/resistor_values.html

author: Marc M.
author_rank: Regular Contributor
timestamp: July 15, 2014, 04:53:56 pm
content: I'll toss my hat in the "- just learn it - it's only 10 colors for pete's sake" circle. If it only applied to TH resistors, I could understand why folks may not really have a need. But if you pay attention, it is used for far more than resistors. A very common example is ribbon cable which normally follows the resistor color code for sequence. This makes it very easy to ID the terminals of a connector if let's say you need to check a voltage on pin 17. In one of Fran Blanche's videos about the Apollo board that Dave just did a video on, an earlier Gemini board she showed had what appeared to be it's connector pins color coded using the resistor sequence also. I've run into it in a lot of other places over the years. At my day job I repair CNC machining centers and I often have to replace components that were hand wired using wire markers to ID wires. Over time the wires get coated in coolant mist that degrades most types of markings. I bought paint markers to cover the resistor code and use them to mark each wire in sequence. It's a very fast way of identifying things when you have a bunch of them.

author: SirNick
author_rank: Frequent Contributor
timestamp: July 15, 2014, 07:00:56 pm
content: Quote from: free_electron on July 14, 2014, 09:21:58 pmI suspect that technique would be extremely error-prone. Color-blindness notwithstanding, ifyoucan't tell the color code, your phone's crappy camera will probably fail utterly. We're not talking about high-contrast barcodes here.Quote from: Rigby on July 15, 2014, 02:12:28 amI regularly reinvent wheels for this reason. One current project: Write an embedded TCP/IP stack. Yep, there are plenty of proven options already, and it's not a casual weekend task. Still, as a network engineer by trade, getting my own code to trade packets with another host is an opportunity to understand the realities of network protocols that is (IMHO) way more beneficial than cramming PDFs to take yet another vendor cert test. I've also written an open framework media player for much the same reason (to help discover audio file formats and digital audio processing.)

author: eneuro
author_rank: Super Contributor
timestamp: July 15, 2014, 07:45:21 pm
content: Quote from: SirNick on July 15, 2014, 07:00:56 pmIt might work, but of course I've no time to play with crappy phones's apps, but I have one project where OpenCV''s computer vision tools will be used, so as warm up I'll try autodecode resistors in real time just by pointing cheap USB camera with customized LED light which could help autodetect those colored things on PCB and mark them with its resistance using artificial neural network instead of human brainI was involved in a few research computer vision projects in university sometime ago and played with artifical neural networks & genetic alghorithms, so it will be interesting challenge to detect those crapy resistors via image processing, because of course enetring its colors to phone app is nonsense and losing of ones timeQuote from: cellularmitosis on July 14, 2014, 11:17:21 pmNice, so let me autodecode them and show & log to file this way. One can verify if colors were well processed by image recognition software

author: bwat
author_rank: Frequent Contributor
timestamp: July 15, 2014, 07:50:14 pm
content: Quote from: SirNick on July 15, 2014, 07:00:56 pmYep! Between declarative knowledge (know-that) and procedural knowledge (know-how), I'll take procedural.Edit: unfunny joke removed.

author: Rigby
author_rank: Super Contributor
timestamp: July 15, 2014, 08:24:37 pm
content: Quote from: SirNick on July 15, 2014, 07:00:56 pmOpenCV can probably do it. Phones usually have an LED of a known color that can shine onto the target, which could make it a lot easier to recognize colors.I believe someone earlier in the thread linked to such a tool. Here's something I found, which may or may not be the same as what was posted earlier, I haven't looked.

author: David_AVD
author_rank: Super Contributor
timestamp: July 15, 2014, 09:09:46 pm
content: Quote from: TerraHertz on July 15, 2014, 02:28:02 pmDeliberate error above to see who's paying attention?Off the top of my head the E24 set is: 10 11 12 13 15 16 18 20 22 24 27 30 33 36 39 43 47 51 56 62 68 75 82 91Beyond that I have no idea...

author: eneuro
author_rank: Super Contributor
timestamp: July 16, 2014, 09:35:05 am
content: Quote from: Rigby on July 15, 2014, 08:24:37 pmThis link only shows resistors detection on white background and one at the time.Red line is drawn on this live cam but resistors value should be overlay'ed there aligned with resistor imageIf someone did it, it means it is easy to do it yourself better

author: TerraHertz
author_rank: Super Contributor
timestamp: July 16, 2014, 12:41:10 pm
content: Quote from: David_AVD on July 15, 2014, 09:09:46 pmOops. Ha ha, actually that's a typo not a memory slip. I didn't even read what I'd typed.82Anyway, good opportunity to add that knowing the E12 series, and the color codes makes it easier to work out what ambivalent colors must be. Brown, red and orange paints, that are sometimes barely differentiable... 22 vs 33 can be a hard one, except even then you can look at other resistors on the same board that used the same paints, and figure it out. Is there a 12 or 39? Then you know the precise colors for 2 and 3.I think I learned the color codes when I was about twelve. Brown-Red years old.

author: Zbig
author_rank: Frequent Contributor
timestamp: July 16, 2014, 07:56:32 pm
content: To me, using computer vision software to decode resistor code instead of using an autoranging multimeter or your memory, is like building an android (as in humanoid robot, not a smartphone OS) and making it play a real piano instead of getting a CD/MP3 player (assuming your intent was just to listen to some music).As for the original poster, judging from his announcement, he's just learned a new useful skill (mobile app development) and it couldn't possibly be a bad thing, no matter how you look at it.And yes, I'm aware I'm contradicting myself a tiny little bit

author: eneuro
author_rank: Super Contributor
timestamp: July 16, 2014, 09:32:55 pm
content: Quote from: Zbig on July 16, 2014, 07:56:32 pm... automated image processing system to detect on manufactured PCBs boards defects and verify SMD soldering quailityResistors autodetection it is only warm up to more complicated tasks using OpenCV realtime image processing capabilities with artifical neural networks.It is much more interesting than writting boring simple phone app... to compute resistor value based on entered color data...There are other ways today to interface computers than entering data manualy to those small useless phones

author: Rigby
author_rank: Super Contributor
timestamp: July 17, 2014, 01:40:15 am
content: Quote from: eneuro on July 16, 2014, 09:32:55 pm"I know you're upset right now, so I'll pretend you didn't say that."

author: AndyC_772
author_rank: Super Contributor
timestamp: July 17, 2014, 08:48:27 am
content: Quote from: Zbig on July 16, 2014, 07:56:32 pmI wonder if Asimo can do that yet?

author: eneuro
author_rank: Super Contributor
timestamp: July 17, 2014, 09:51:07 am
content: Quote from: Rigby on July 17, 2014, 01:40:15 am"Modern" "smart" phones are really useless while you can loose your sight looking into its small screens, forget about touching this thing and try to hit small edgeAlso its WWW like interfaces with "patented" not clear visible buttons is a total miss.But the worst thing is they are very big and I used to carry nothing bigger than waterproof wristwatch 1inch2 (6cm2) optionally with GPS CB radio and automatic heartbeat monitor to be able autocall SOS when in trouble or live danger situations.There were many those useless samrtphones on MH370 board and no one was found so far or called SOS even using Morse coded radio.. while its.... MEMS accelerometers & gyro might detect unusual G forces like in airbags... so theese devices are useless and only marketing toys so far...

author: Zbig
author_rank: Frequent Contributor
timestamp: July 17, 2014, 10:31:16 am
content: Quote from: eneuro on July 17, 2014, 09:51:07 amUhm, so basically they're too small while being too big, yeaaahhh... I'm not sure what your problem is, but chances are, you're living in some weird parallel universe.

author: eneuro
author_rank: Super Contributor
timestamp: July 17, 2014, 07:52:23 pm
content: Quote from: Zbig on July 17, 2014, 10:31:16 amRather in the world where machines do not tell me what to listen to and what to watchWe have to be prepared for new challenges and privacy steel attempts while MIT releases open-source software that reveals invisible motion and detail in video:It is amazing what kind of information can be taken from analysis using software like this for image color frequency changes analysis

author: noah_fakelastnamelike_bob
author_rank: Regular Contributor
timestamp: July 17, 2014, 08:36:57 pm
content: this is an amazing idea and i am lazy so i did not read every thing but i have an idea.this is awesome but you should make this eventually* an add on to a bigger app that does calculations for everything and not just resistors and no i don't mean getting into the thickness of traces but like inductance and other simple* things like that.and im sure since windows phone use a really simple programing language(or at least well known) someone with your permission could make one with the same name and everything.i currently use electrodude, for this and i also use ohms law caluclator to find resistance(ohms) voltage(volts) current(ampere) and power(watts).so my idea is just expanding and keep in mind i was to lazy to read every thing else so don't yell at me for repeating some one.thanks for your time...

author: Rigby
author_rank: Super Contributor
timestamp: July 17, 2014, 08:48:38 pm
content: The Android Wear platform can monitor your heartbeat, and there are at least a couple of apps that can call 911 for you in an accident.Don't discount technology out of hand. The width and breadth of possibility gets larger every single day, and when you dismiss things out of hand you necessarily make an uninformed judgment.Cheers.

author: eneuro
author_rank: Super Contributor
timestamp: July 18, 2014, 01:46:56 pm
content: Quote from: Rigby on July 17, 2014, 08:48:38 pmReally?I do not think so and in real life danger situations it is simply not possible communicate without good radio, eg. when flying "comercial" aircrafts typical above 10km/33000 feet altitude 900kmh/560 mph .The Cellphone and Airfone Calls from Flight UA93QuoteSo, it is true that those devices are useless too many times, just when needed.BTW: No aircrafts around Ukraine Donetsk battle field after last MH17 crash....http://www.flightradar24.com/48.14,37.28/7End of off topic.

author: Rigby
author_rank: Super Contributor
timestamp: July 18, 2014, 02:18:56 pm
content: Quote from: eneuro on July 18, 2014, 01:46:56 pmAutomatic can do it.https://play.google.com/store/apps/details?id=com.automaticthere was another that I found the other day, but I can't find it now. Any app that can connect to a Bluetooth OBD-2 dongle can detect a crash, call 911 for you if there's service and read to the responder your name, location, and severity of crash. So knock it off with the "I have no idea what I'm talking about and you're wrong" crap.I wasn't talking about aircraft, by the way. I don't know where the hell that came from. If you have further scenario restrictions, lay them out.You're saying smart phones are useless. I'm saying you're DEAD WRONG.

author: eneuro
author_rank: Super Contributor
timestamp: July 21, 2014, 01:53:23 pm
content: Quote from: Rigby on July 18, 2014, 02:18:56 pmSo, look into data how many people a year and how many hours spend in aircrafts-if they a not able to use his "smart phone" eg. in the case of emergency while @ 10km/33000 feet altitude this means this thing is useless without its base stations.Can you call even another person of the same flight seating a 10-20 meters away without ground ba$se $tation? I do not think so..Simply you can not communicate, only play stupid games on its a few inches '' screens.It is clear, one needs good radio not those useless phones in many cases.I need one too and It could be nice to have CB radio in wristwatch-no Android needed, but a piece of electronics...

author: Rigby
author_rank: Super Contributor
timestamp: July 21, 2014, 07:28:44 pm
content: Well, if you're flying an aircraft without an FAA approved radio, then what happens to you is your own damn fault.No one ever claimed that an Android phone would serve in an emergency on an aircraft. I don't know why you're so high and mighty about that point, when no one ever contested it.If you want to argue for no reason, that's fine, but leave me out of it.

author: eneuro
author_rank: Super Contributor
timestamp: July 22, 2014, 02:52:09 pm
content: OpenCV resistors scanning so good so farcvrescantrained to recognise resistors colors.It is time add realtime camera support, a few DIY power leds and convert it to Android app to be able run on tablet with its crappy camera and see what happends

author: nadavt
author_rank: Newbie
timestamp: July 26, 2014, 03:16:07 pm
content: resistr is now available! visit our site athttp://resistr.coor search the AppStore to download.Have Fun!