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I have bought some resistors and I am trying to find their value. The thing is that in class they taught us that you use the gold strip to find which is the right side at first and then you check the other colours strips. The thing is that the resistors I got don't have a gold strip and they have more "other-colour" strips. I have searched in google extensively and also in this site (having found relevant questions) and I have found that resistors come in different styles but I have not found how to "translate" them in their value. Also most sites are calculators to put the colours and calculate the value but I don't know which is the side with which I must begin. These are some of my resistors:

enter image description here

There is this post but these resistors begin with same colour in both sides.

How do I find their value?

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  • \$\begingroup\$ First count the stripes and subtract one. That gives you the number of digits. Then decide which of the end stripes has that value. That is the precision stripe. The instructions you were given assume the precision stripe is always gold, which isn't the case. \$\endgroup\$ – user207421 Oct 31 '14 at 22:41
  • \$\begingroup\$ Both stripes have the same colour, orange and red as you can see in the picture. :/ \$\endgroup\$ – Adam Oct 31 '14 at 22:46
  • \$\begingroup\$ If you have any resistors with the same spacing on each side, see this question/answer about how to distinguish them: electronics.stackexchange.com/questions/348599/… \$\endgroup\$ – piojo Feb 3 '18 at 6:57
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The trick here is to look at the spacing. It's subtle, but when you know what to look for it's obvious.

The right-hand band of the top resistor has a slightly wider space infront of it. That's the % band.

So you have Brown Black Black Silver, at Brown %, which is

100×10-2Ω at 1%. (1Ω±1%)

The bottom one, the left hand band has a slightly wider space. That's the % band. As I say, subtle differences. The top one is more obvious than the bottom one.

So you have Brown Black Black Brown at Brown %, which is

100×101Ω at 1%. (1kΩ±1%)

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  • \$\begingroup\$ Thank you very much. All the other answers suggested that the second one may be one of two values and must be tested, why you suggest for sure that it is 1 kOhm? \$\endgroup\$ – Adam Nov 1 '14 at 0:40
  • \$\begingroup\$ Because the gap between the two brown stripes is very slightly larger than the gap between the other stripes. It's a very tiny difference, only noticeable if you're looking for it. \$\endgroup\$ – Majenko Nov 1 '14 at 10:47
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If you can't figure it out by using a resistor chart, you could easily find their resistance by using a multimeter on the "ohms" setting.

Depending on what multimeter you have, you may or may not get the exact value of your resistor so it would be wise to take it as a ballpark measurement and then compare it against the resistor chart and find out what the resistance should be.

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  • \$\begingroup\$ I am ashamed to admit it but I have started just recently to work with electronics as a hobby so I don't currently own a multimeter. \$\endgroup\$ – Adam Oct 31 '14 at 22:40
  • \$\begingroup\$ Don't be ashamed, everybody starts somewhere and its awesome field. Unfortunately I don't know of any places where you could just go and have them measure it for you. Pretty much every "blue-coller" service will have one, apart from a plumber maybe. Most dads have one in their arsenal \$\endgroup\$ – Funkyguy Oct 31 '14 at 22:43
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    \$\begingroup\$ Don't worry I know places which can do it dor me. There is a hackerspace near my home. But it is a useful knowledge to know to do it even without a multimeter and it is handy sometimes. Like now. :P \$\endgroup\$ – Adam Oct 31 '14 at 22:45
  • \$\begingroup\$ Big-box hardware stores usually sell DMMs these days. Granted they're most likely electrician's multimeters, but they beat not having one at all (I wouldn't trust them above 400V though). \$\endgroup\$ – Ignacio Vazquez-Abrams Nov 1 '14 at 0:32
  • \$\begingroup\$ When you do get a multimeter (and you WILL need one if you continue with electronics) be sure to only hold one end of the resistor with your hand. With high value resistors (over ~50K) your body resistance in parallel with the resistor you are measuring will affect the reading if you hold the resistor leads against the meter probes with both hands. \$\endgroup\$ – Peter Bennett Feb 3 '18 at 7:28
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The top one is fairly easy, because you would never see silver as a value, only as a multiplier. This would mean:

Brown-black-black-silver-brown = 1 0 0 * 0.01 +/- 1%, so it's 1 Ohm +/- 1%.

The second one is a little bit harder, because you have 2 options:

  1. Brown-Brown-black-black-brown = 1 1 0 * 1 +/- 1%, so 110 Ohm +/- 1%
  2. Brown-black-black-brown-brown = 1 0 0 * 10 +/- 1%, so 1kOhm +/- 1%

This is where standards come in handy. In electronics the E-series are commonly used. These are standard values for transistors. Resistors in the E12 series are very common (10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82), so it's most likely that the resistor is a value within the E12 series, which would vote for the second option.

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Those are 5-band resistors, which means they're usually 1% (occasionally some other tolerance, but brown band on the right means 1%). So the brown band for 1% will go on the right, and you read it from the left.

Silver is never a starting band, so the top one is 100 with a multiplier of 0.01, so 1.00\$\Omega\$ 1%.

The bottom one is either 100 with a multiplier of 10, or 1K\$\Omega\$ 1% or 110 with a multiplier of 1 or 110\$\Omega\$ 1% (either one is a standard E96 value, so it's hard to be sure without measuring it. If you put it across a 9V battery and it quickly gets too hot to hold it was 110 ohms (but might be out of tolerance now!).

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Take the resistor, hold it horizontally with your fingers. Notice the color strips. Always keep Gold,Silver or large blank space to your right hand side. Start counting from your left. The value = xy*10^(z) (+-)(5% or 10% or 15%) x, y and z are the values of the colors.

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