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[Tutorial] How to read Resistors.

So I realized while working on the graphic equalizer just how useful this bit of knowledge could be.

everything else is labeled, be it capacitors, diodes, Integrated circuits, Transistors, etc.
but not resistors, not exactly.

instead they have this nicely implemented color code, one which is handy to have available to reference and once you pick it up makes decoding them at a glance easy... to the point I kinda wish they used something similar for other components.

So capacitors typically have colored bands on them with 10 colors to indicate various things.

the first two or three bands indicate numbers 0 through 9 the 3rd or 4th band depending on if it's a 4, or 5 band capacitor is usually a multiplier, the next color band is the tolerance or how much of a tolerance +/- a resistor can tolerate.
and the last color band is only on 6 band capacitors which is a temperature coefficient though that doesn't come up often

most often you'll encounter 4 or 5 band capacitors in the wild so we'll focus on these.

for the first two or three bands it's.

0 Black
1 Brown
2 Red
3 Orange
4 Yellow
5 Green
6 Blue
7 Purple
8 Grey
9 White

then for the next one it's the multiplier so it's
0.01  Silver
0.10  Gold
1       Black
10     Brown
100   Red
1K     Orange
10K   Yellow
100K Green
1M     Blue
10M   Purple

you won't find one above it but ...
100M grey
1B White

not likely to encounter that though except for some really specialized stuff.

then there's a space followed by the next band making it easy to identify which one is the multiplier band.

finally there's the tolerances, usually that's +/- a percentage of the total ohms the resistor is rated for.

10% Silver
5% Gold
1% Brown
2% Red
.5% Green
.25% Blue
0.1% Purple.

temp coefficients on a 6 band capacitor are
100ppm Brown
50 ppm  Red
15 ppm  Orange
25 ppm  Yellow

Similarly you might come across one with only 3 bands, usually really old ones.

this one follows the same rules as a 4 band but doesn't have the tolerances marked on it.

first two color bands are numbers, third one is a multiplier.

with all that in mind let's practice decoding a couple

[Image: x18Kq3rt.jpg?1]

These are real examples of 4 band resistors

Red Blue Red Gold
26 X 100 +/- 5%
or 2.6k Ohms 5%
that's 26 times 100 = 2.6 thousand ohms or 2.6 Kiliohms

Yellow Blue Yellow Gold
46 X 10K ohms +/- 5%
460k Ohms 5%

Green Blue orange Gold
56 x 1K +/- 5%
56k Ohms 5%

here's a nice graphical chart if you get hung up and to save time you can also use this code translator if you don't want to sit there figuring it all out.

[Image: Vydsx7S.gif]
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