Tips to memorize resistor color codes?

Discussion in 'Homework Help' started by trap_lord, Nov 11, 2015.

  1. trap_lord

    Thread Starter New Member

    Nov 11, 2015
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    Hi, I'm taking an electronics test, and our teacher informed us there will be quite a few questions on resistor color bands. On these questions we will be asked to determine its nominal value, and its upper and lower possible values. My concern is if I'll be able to memorize the large color code. Any tips?

    Edit: Only working with 4-color band resistors
     
  2. absf

    Senior Member

    Dec 29, 2010
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    Can you make an easy sentence with "BBROYGBVGW" and study it by heart? That would represent the color code from zero to nine of the resistor. During our electronics course someone did figure out a bad sentence I dont like to mention it here. :(

    Allen
     
  3. trap_lord

    Thread Starter New Member

    Nov 11, 2015
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    Yeah actually my teacher made one, but for the life of my I can't remember it. I should have wrote it down. ):
     
  4. WBahn

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    There are several mnemonics you can use. Some of them are easier to remember than others, particularly if you don't mind ones that are VERY politically incorrect.

    But the one I always found made the most sense is just to think of it in terms of how it most likely actually came about.

    What are the colors of the rainbow: ROY-G-BIV. Now, remember that Indigo was removed so be sure to skip it. That gives you six colors, in order. To get the rest we add four colors, two on each side, that go from black to white. On the low side, we add black and brown, then our six rainbow colors, then we add gray and white.

    For the tolerance bands, we have none, silver, and gold. These are in order of most valuable, namely 20%, 10%, 5%.
     
  5. #12

    Expert

    Nov 30, 2010
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    That's exactly how I do it, but that sequence was learned across time. First I knew the BOY-G-BIV from grade school, then I memorized Black, brown, gray, white, gold silver. That might be less natural to a person who didn't learn the rainbow thing as a child. Just sayin'...It's my method too, but I never suspected that I invented the best method purely by chance.

    Any other people have a method?
     
  6. trap_lord

    Thread Starter New Member

    Nov 11, 2015
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    Yeah I remember roy-g-biv from grade school too. Adding the extra colors is not a problem. I think what's going to throw me off is the tolerance column since they skip a few rows, go in order, and skip a few more. I guess there's some logical explanation as to why it's arranged this way.
    Oh well, guess I'll have to study and practice more. Thanks for all the help guys.
     
  7. WBahn

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    I first learned the color code using a particularly non-PC mnemonic involving bad boys. Since I was never big on long-term memory of memorized things, I had long since forgotten ROY-G-BIV and, somewhat surprisingly, it was years later that I just coincidentally noticed that the middle of the resistor color code was the colors of the rainbow. IIRC, it was someone saying the colors of the rainbow and me noticing that it went in the same order as the interior of the color code. Until then I thought it was just how someone had decided the colors were ordered in going from black to white, but I could never make since of it since blue seems "blacker" than yellow, for instance. Slap on forehead time, it twas.
     
  8. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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    The two non-PC one's I remember start Bad boys ... and Batman.

    A PC one starting with bad boys, according to the NEETS module 1 is:

    Note this does not cover the tolerance band.

    The batman non-pc version includes the tolerance band.
     
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  9. GopherT

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    Nov 23, 2012
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    I must have gone to an even less PC high school.
     
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  10. JoeJester

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    I heard them in the military ... after high school.....
     
  11. WBahn

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    I was taught the Bad boys one in high school and college.
     
  12. atferrari

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    After maybe 40 years of starting with this hobby I recently learnt about nemonic help for colors.

    Had I to do that I would use one with expressions familiar to me in my own language.

    Tell you a secret: add a rude expletive (those that you never use, of course!) if it fits to the sentence. It works marvels.
     
  13. #12

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    I have to say...good suggestion. Have you ever heard of, "cuss like a sailor"?
    Yeah.
    I met a sailor in 1968.
    I still have one of those stuck in my head.
    I haven't thought of that one for 20 years, but today I check for old memory devices, and there it is, all 17 words of it.:(

    ps, sorry about the typo in post #5.

    Seems to me...if it isn't blank, 10% or 5%, it's the digit of the color. Brown is 1%, red is 2%. Right?
    I often forget the dividers. Divide by 10 like a 1.2 ohm is Silver and divide by 100 like 0.12 ohms is Gold.

    Capacitors are a whole 'nuther thing. If I had invented +80%/-20% capacitors I would have dumped that batch in the dust bin and tried again. The thing to know about that is: when those were invented, we were still building vacuum tubes like a ship in a bottle and making resistors by baking a mud of clay and carbon. I can easily imagine it was a choice between trying to shave mica real thin or inventing some ceramic slurry and baking it into discs like making cookies.:D
     
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  14. atferrari

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    I know the expression. I do not think that they use to curse heavier than in many other "rough" activities but it well may be when maneuvering and something tends to go wrong.

    Anyway, the strongest I ever heard came from a crane driver ashore, more than 10 years ago, consisting of a detailed description of something, involving a parent. There was a reason: the crane left the piece to go in free fall.

    Me? I have no idea how I learnt those colors and if asked to tell equivalences I need to THINK. If for any reason I need to look for any particular value in a tray with a hundred of them, I really do not know how I do it because I do not look for a precise color (or a specific combination).
     
  15. bertus

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  16. WBahn

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    In my experience, the only person that can cuss better than a sailor is a sailor's wife! :D
     
  17. Sparky49

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    Jul 16, 2011
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    I suspect the version we were taught in school was the same as Bad Boys, but started even less PC as Black Boys.... Which helps to remember which way black and brown are.

    To confirm, does it end with Violet Gives Willingly?
     
  18. WBahn

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    Yep. Or rather, the version I learned actually ends beyond that with "Get Some Now" for the tolerance bands.

    I'm not at all surprise that it used to be Black Boys (I think I may have even heard that before).
     
  19. Sparky49

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    Jul 16, 2011
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    I was taught this in 2008 I think. :p It was alright though, our teacher was a black Jamaican - nevertheless the class was stunned when he made us learn it. xD
     
  20. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Ours was even more politically incorrect!
    I see the latest release of Kicad has a drop down resistor colour code chart which is handy.
    Max.
     
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