# HOW TO – How to read a resistor (PDF)

R. Stern writes -

“I work in a computer lab with a physical computing studio, and recently I cleaned out the component closet. It occurred to me that the reason we had a build up of unlabled resistors was because noone knew how to read them without the Resistulator widget or a resistance calculator website, so I made a sign to tack into the cabinet itself for offline calculation. You can download the PDF for your own use. “Link.

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### 11 Responses to HOW TO – How to read a resistor (PDF)

1. I hope I don’t get in trouble for this but as I am a R&D electronic tech and having got my education from Uncle Sugar here is a little ditty that might help,

Bad Boys Raped Our Young Girls But Violet Gave Willingly, Get Some Now

As you can tell with a little thought that is the resister color code including the tolerence bands. If I get enough positive feedback I’ll make a pretty picture of it and post it for ya

2. PLC.Doctor on said:

There is a typo in the example.
It should be:
Resistor value = 20 x 1000 = 20K ohms

3. RobTheEngineer on said:

This is what I did – I labeled each resistor bin/drawer with the color code. I have done this for several places that I’ve consulted.

This is an example: USBmicro resistor labels from USBmicro

The small drawer labels are available from that site as color pdf files.

4. I’m new to this but his little chart on the pdf says brown is 1 and not 0. Wouldn’t that make his example on the pdf, red brown, be 21 and not 20?

5. bekathwia on said:

Hey all, thanks for checking my work. I fixed both typos, and updated the files on my site. D’oh!
-R. Stern

6. RussNelson on said:

“Unlabelled resistors”? You mean somebody scraped the stripes off?

With a little bit of practice, you don’t need to interpret the resistor color code. You just look at it and say “Oh, that’s a 6.8K resistor”. In fact, I couldn’t tell you what the colors for that would be, but I know one when I see one.

7. philliptorrone on said:

RannFox – you won’t get in trouble and i’m not going to delete your comment – but here’s something to think about… all these new people learning electronics could learn something better than this offensive mnemonic – i realize it’s still said and taught all the time, but we don’t need to continue this. if you look at the history of this mnemonic it’s been pretty awful.

8. bhelverson on said:

Rannfox, I learned that one from an old Navy electronics guy. And I stll use it today. I did hear one that did not involve sex, but who can remember something like that?

9. philliptorrone on said:

again – why don’t we use this opportunity to kill a bad mnemonic.

10. Julolidine on said:

In the multiplier column, black’s value should be 1 and not zero. I think it also makes it a bit clearer if you were to label the multipliers via factors of 10.

11. Augustine on said:

I, appreciate the assistance coming from this site. Pls, you people should continue with it and even more.