Resistor Colour Code??

I'm totally new at this so please be gentle :shock:

I've just started on my first project (SSL clone) and I have started buying parts - I have two questions(after trying to search for info):

a) I have a Resistor Colour Code Calculator so I can convert the colour codes on the resistors to values - Is there anyway to see on the resistor what side/end of the resistor I should start decoding the colour code?? (or will I end up with the same value no matter which end on the resistor I start decoding at??)

b) After testing the resistor does it matter how I place the resistor on the PCB - I know, of course :green: , that the resistor has to be placed in the holes on the PCB specific for that particular resistor - but does it matter how I turn the resistor or is it important that it is placed in the right direction??

Hope you understand what I'm talking about :roll:

Hi Hulk,

I never trust the color code. I always test every resistor with a meter before I put it in. I hope to avoid the nightmare of finding a wrong value resistor later. It doesn't matter which direction you put in the resistor - either way is fine.

:thumb: :thumb:

most often the colour code is the ring closest to one end. But you'd better still check with ohmmeter every time..!

Jakob E.

If it has gold or silver ring it is placed to the right. The rightmost ring is tolerance marking

tolerance markings +/-

silver 10%
gold 5%
brown 1%
red 2%
green 0,5%
blue 0,25%
purple 0,1%

there are good online calculators that show color codes...

Text is finnish but there is a pic if yscroll down...
http://wwwk.heltech.edu.hel.fi/ideaport/laskurit/vastuslaskin.htm

http://www.electronics2000.co.uk/

Ok Thanx

I'll check the resistors with a meter before soldering :thumb: :thumb:

Yeah, it's easy with 5% or 10% resistors because of the gold or silver tolerance bands, but it can be confusing with tighter-tolerance resistors. I still get thrown off sometimes when using 1% metal films.

If you read it one way and the value makes no sense, then it's likely the other way. That sometimes helps. For example,

Yellow-White-White-Red-Brown could be one of

49.9k, 1%
129G, 1%

The 129G 1% is wrong, after you've been doing electronics for a while that becomes pretty obvious.

Brown-Black-Black-Brown-Brown is more difficult. It could be 1.00k 1% or 110 ohms, 1%. Either is valid. Use an ohmmeter if there's any doubt.

Hope I did the conversions ok, I usually triple check them but I didn't today.

This is a nice chart to have also. I has every resistor value known to man. If you read a %1 backwards, chances are it will not be on this chart.

You have to multiply by factors of ten on the chart to get your value.
Print this out if you don't have it already.

Nice chart.... and it comes with CJ's shadow at no extra charge! :razz:

Sorry about the shadow. I am at work so I had to take the pic hidden in the corner.
And it actually does not have every resisitor, early Telefunken stuff had some weird values.
I will retake the pic after hours.

While were at it, here are those cap color codes again: