Resistor colour bands

Just starting to put together my Gen 2 electronics and I was having problems figuring out which resistor was what so I searched and found a cool little webpage: [www.micro-ohm.com] which allows you to put in the resistor rating and get the colours or vice versa. Note that you need to choose the carbon film option rather than metal film.

Maybe this should be linked to from the instructions.

Also, for me at least, black and violet are easy to get mixed up in the winter sunlight.

reece.arnott Wrote:
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>
> Also, for me at least, black and violet are easy
> to get mixed up in the winter sunlight.
>

Which is why I just measure the resistance of all the components with my digital meter before I solder anything in.

I have terrible color vision. I fail the Ishihara tests [www.toledo-bend.com] every time.

Fortunately, there are only a handful of common resistor values. The first two color bands are almost always:
brown black = 10
brown red = 12
brown green = 15
brown gray = 18
red red = 22
red violet = 27
orange orange = 33
orange white = 39
yellow violet = 47
green blue = 56
blue gray = 68
gray red = 82

That covers the 20% and 10% tolerance resistors. There are other values (for 5%, 2% and 1% tolerance) but you hardly ever come across them. I've got those 12 combinations memorized, so I can pretty much figure it out by process of elimination. For example, if I see something that looks like gray blue yellow (860k), I know it's really green blue yellow (560k).

Another handy thing is that the third band is almost never blue, violet, gray or white, which narrows down the possibilities quite a bit.

The hardest for me to tell apart are brown green and brown gray. I usually have to pull out the meter for that.

Edited 1 time(s). Last edit at 08/16/2008 08:00AM by Steve DeGroof.