28 replies to this topic

[Dan Morphis]

Hard to tell how much people are color blind. Only males are affected.

Not 100% true, females can be affected by color blindness as well, but the rates are much lower. 8% for men, and 0.5% for women - Color blindness

[Christoc]

I saw this today, haven't been able to figure out if it will take a picture and analyze though http://itunes.apple....und/id492487671

[Mario Vernari]

Not 100% true, females can be affected by color blindness as well, but the rates are much lower. 8% for men, and 0.5% for women - Color blindness

Perhaps that's the way most men are getting married?...

[Stefan]

Perhaps that's the way most men are getting married?...

But seriously, those colours. I've got a good sight. But yesterday I had a couple of -blue!- resistors in my hand and couldn't read the values at all. I took my multimeter, but that's never 100% accurate (I've got cheap tools). I learned that they used coloured rings because they wouldn't ware off. But if they showed text like ICs, transistors, capacitors, and all those other components did, it would make live way easier. Text can be magnified, colours can be tricky.

[Mario Vernari]

Stefan, didn't read the colors correctly? ...isn't related to the last Saturday event?
Okay, just kidding...

I learn the color code since childhood. You know, for children is lot easier to learn, and I never forget it.

Most of the time I've used EIA 5% resistors series, which are -basically- a bunch of "color pattern". Thus, at first glance, you don't actually read the colors, but recognize the "pattern". I guess it's much like reading a number, or multiply by mind (right?)
These patterns are easily recognized, because there are three colors, and a gold ring (silver is for 10%).


...BUT...<br class="Apple-interchange-newline">
When I deal with 1% or 2% resistor, reading it is much harder.
First off, there is a ring more, then the tolerance ring is *NOT* a special color (gold, silver), but...brown (1%) or red (2%). Which is really confusing among the *real* value.

Capacitors.
Stefan is almost right, but isn't everything shining.
While resistors have their own color coding, capacitors never had one. Worse: every company decided its own method for indicating the value.
EVEN WORSE, measuring the capacity is NOT as simple as measuring a resistor.
Thus you may bump to a ceramic capacitor with a printed "472". This is pretty easy: it means 47 and two zeroes, = 4700...what?...well, yes...pico Farads. But what when you read "120"? Is it 120 pF or just 12 pF?
That is for small capacitors, but bigger are using "u22", meaning 0.22 uF.
Finally, when you read "63K" on a disc capacitor, is *NOT* 63.000 pF! Instead, it means 63V "Keramik" (from German).

Transistor.
Past in the '70-'80 there was a...raw "rule"...about transistor manufacturer.
BCxxx, BDxxx, OCxx were European: mostly Philips, SGS, etc;
2Nxxxx were US;
2SAxxx, 2SBxxx, 2SCxxx, etc were Japanese.
What if you read "D123"?...Well, you must "know" that Japanese engineers wanted to save space, instead of "2SD123".

Thanks God that someone brought us the "standards"!
Cheers

[Darrin]

I solve this problem by keeping my resistors in divided containers. When I purchase them, the packaging says 10k, so I put them in the 10k bin. This works great until I bump the container onto the floor and 500 resistors scatter everywhere! Then I'm back to square one!

[Stefan]

I solve this problem by keeping my resistors in divided containers. When I purchase them, the packaging says 10k, so I put them in the 10k bin.

I do the same

But when analysing some electronics, or replacing a broken part, it's good to identify it correctly

[DanA]

I saw this on AdaFruit this morning: http://www.adafruit....app-for-iphone/

Dan

[jwjames83]

I saw this on AdaFruit this morning: http://www.adafruit....app-for-iphone/

Dan

Bingo!