Resistor suggestions for colorblind person

Question

I'm a developer who has always had a love of the low-level electronis, but I have always been intimidated by it since resistors all seem to be color based and as a color-blind person, this is difficult to work with.

So my question to everyone here is if they know a good, practical way, to work with resistors (mark them, shelve them, etc). This is the one thing that keeps me from doing more electronics hobby stuff since I hate spending an hour trying to find a 10K resistor in my collection of a few hundred.

Answer 1

Try not to be intimidated by the colours, I think it should be easy to get round this. Certainly I wouldn't let it put you off electronics, too much fun to be had :-)

You would ideally have them sorted into separate marked drawers anyway. For example these storage cabinets are what we use. It has 44 separate drawers that can be divided themselves into three parts with dividers, and a slot at the front for a label card. There are many types/sizes around so find something that suits your needs.

That gets you "pretty certain" that the resistor you take out of the drawer will be the right one.
To make sure though, I would maybe buy a cheap multimeter (or repurpose one) and set it up as a value tester. If you make a little frame to set the probes just the right distance apart, you can quickly place the resistor between them and double check it's value.

This is more for loose resistors, but another option is to keep them in their packets in the drawers until needed, then take out as necessary. Though you can get errors in the packaging/component it's very very rare, and if you test one you can be even more sure all the rest will be the same anyway.

This should ensure you have very little chance of making a mistake (probably about as much as anyone else, many don't go by the colour bands anyway)

Most other components nowadays have values/codes marked on them, and if you are working with SMD (most) resistors do too - it's the unmarked capacitors that are the pain (for everyone) there :-)

Answer 2

I use only surface mount resistors. Most 0603 and larger resistors are marked in high-contrast silkscreen with the numerical value of the resistor:

You may need magnification to read 0603 and 0805 markings.

The smaller ones are not marked at all. You get used to dealing with them. Just keep the different values in separate bags or bins. It is no different than leaded resistors when you can't read the color bands.

Answer 3

If you search the net for these words: color recognition blind iphone software you get more then enough to start with. Add resistor to the words list and joy is all yours.

1. Ohm sense is an iPhone app that will take a picture of a resistor and calculate the value based on the color bands.
2. 20 iphone apps for color blind
3. Someone else has the same problem as you do. Another one, too.

You can also search for android instead of iphone if that is your preferred mobile platform.

Answer 4

If you're working with resistors you'll likely have a multimeter on hand. It only takes a moment to check the resistance with the meter. If it's something you need to do often, it might make sense to dedicate a cheap meter and build a jig to hold the probes in some convenient position.

Answer 5

Have you tried looking at resistors through different color filters? I doubt that any one filter would allow you to distinguish all ten colors, but would think it likely that you could find a pair that would work. Alternatively, it might be possible to build a "resistor reader" light which would have two or three colored LEDs that blink in different patterns. This would cause the bands on the resistor to blink in patterns that would vary with their color. Some experimentation would be required to determine the best combination of LED colors and blink patterns.

Answer 6

The 1% resistors we have at work are marked with printed digits instead of stripes. The digits work the same as the colors: ABCD is (A * 100 + B * 10 + C) * (10 ^ D). I'm not sure if this is some military thing, but you should be able to see from data sheets if the 1% resistors you're looking at are marked with colors or digits.

Answer 7

At a company I used to work for we used Dale/Vishay parts that had the value printed numerically on the body.

The data sheet had a table that showed how to read the value and tolerance. (I downloaded the example data sheet from TTI, but you can buy the parts from lots of different vendors.)

The parts we used were pretty pricey because we needed low tolerance, but if you shop around and buy in volume you should be able to find them at an affordable price. The vendors we bought from supplied them in boxes of 100 or reels of 1000.

One additional advantage to the numerically coded values is that they're easier to learn. We used to hire high school students to solder boards over summer breaks, and we found that they learned how to read these resistor values much more quickly than they learned the color code.

Answer 8

I tend to either tape 'strips' of resistors to an index card, and cut them off as needed, or have them in a small bag taped to an index card. When starting in projects, i do the same with all the resistors and other components needed, though i often tape them to a circuit diagram - this makes it a lot easier, even if you're not colour blind.

Answer 9

Friends,

1-27-2017 - As a colorblind person with this problem, I looked for but could not find 'OhmSense'; it seems to have disappeared. I DID, however, find a resistor-valuation app for the color-blind, though it has a couple of limitations.

You might check out an iOS app called 'ResistorVision' by Jera Design; you can find it at the app store. Focusing on a resistor against a pale background will allow it to read the bands and give you the values. It does not, however, work with resistors with a blue body or with resistors below 10 Ohms, though they are working on both these issues. Another limitation is that it has trouble working against dark, complex or visually-confused backgrounds, so reading the value of a resistor 'in situ' may be problematic. Seems to work well on the workbench, though, within the limits described above.

Answer 10

I have linked a cheap USB microscope (20x setting) to my laptop. Gives a good fullscreen picture of resistors with colour codes. I have tried searching for a program that will output the colour of the bands as text, i.e. Red, Black etc. when placing the cursor over the band. I had one some years back but cannot find it now or anything suitable for Windows 10. Plenty that will give information as percentages of R, G and B though. Many of these apps are now for Android or IOS but even with a closeup lens the bands are not large enough to work. A real luxury would be one that actually read the bands from the screen automatically but that is perhaps just being greedy!

Answer 11

I would assume that resistor manufacturers are all color sighted. Most color sighted people do not give a second thought to the fact that color actually does not exist. This fact does not prevent them from using a color based system. The system is flawed. One shift in the hue of light shining on the resistor and even a color sighted person will be wrong about the colors they see. Color blind people understand this. Color sighted engineers need to catch up.