MAKE | HOW TO – How to read a resistor (PDF)

Hot Topics:

By Phillip Torrone
Posted 2007/01/26 @ 7:01 am
Category Electronics

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.

Related:

HOW TO – Read color coded resistors – Link.
Read resistors with Resistulator – Link.

In the Maker Shed

Calculator Kit from Spikenzie Labs

Tux Case for Raspberry Pi

BrushBots

Raspberry Pi Starter Kit - Includes 512MB Raspberry Pi

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

RannFox on January 26th, 2007 at 5:47 am said:

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

Reply ↓
PLC.Doctor on January 26th, 2007 at 6:25 am said:

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

Reply ↓
RobTheEngineer on January 26th, 2007 at 6:26 am 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.

Reply ↓
wiljefv on January 26th, 2007 at 6:41 am said:

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?

Reply ↓
bekathwia on January 26th, 2007 at 6:51 am said:

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

Reply ↓
RussNelson on January 26th, 2007 at 2:30 pm 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.

Reply ↓
philliptorrone on January 27th, 2007 at 9:36 pm 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.

Reply ↓
bhelverson on January 28th, 2007 at 6:51 pm 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?

Reply ↓
philliptorrone on January 28th, 2007 at 6:54 pm said:

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

Reply ↓
Julolidine on February 3rd, 2007 at 1:38 pm 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.

Reply ↓
Augustine on September 14th, 2012 at 7:03 am said:

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

Reply ↓