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enter image description here

I have a difficulty in identifying a five band resistor. Color sequence is red, orange, black, gold, and black. It doesn't fit in to normal rules.

Depending on the location of its use I expect that to be around 20 ohms. But I want to know if it is any how special as in low tolerance, or temperature etc.

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    \$\begingroup\$ How about a photo? \$\endgroup\$
    – Andy aka
    Jun 10, 2019 at 13:52
  • \$\begingroup\$ Well it comes out at 23 ohms for the first 4 bands on a 5 color band chart; check the last colour. digikey.co.uk/en/resources/conversion-calculators/… \$\endgroup\$
    – Peter Smith
    Jun 10, 2019 at 14:25
  • \$\begingroup\$ Added @Andyaka. \$\endgroup\$
    – AK11
    Jun 10, 2019 at 15:15
  • \$\begingroup\$ Image added @PeterSmith \$\endgroup\$
    – AK11
    Jun 10, 2019 at 15:19
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    \$\begingroup\$ The photo is not great. You should try to post a better image. Anyway, it looks damaged. Have you tried to measure it in circuit (with power off) using an ohmmeter? \$\endgroup\$
    – Lorenzo Donati support Ukraine
    Jun 11, 2019 at 12:35

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That is likely a wire-wound power resistor with half the windings in the opposite direction so it is non-inductive. That is what that final black band means.

enter image description here

Making it a 23Ω Non-inductive resistor.

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    \$\begingroup\$ Thanks for teaching me something new today! But, could you please provide a link or citation for the graphic that you used. \$\endgroup\$
    – Elliot Alderson
    Jun 10, 2019 at 18:34
  • \$\begingroup\$ @ElliotAlderson I am pretty sure I got that image from Yageo, but I am having a hard time finding a link to it now. I see these a lot in low-value 2 W - 5 W power resistors. You can often see the windings just under the ceramic coating going both ways. I will keep looking for a reference and post what I find. \$\endgroup\$
    – evildemonic
    Jun 10, 2019 at 19:32
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    \$\begingroup\$ Nice find, but for a 5% resistor a 23 ohm value is weird. I'd bet that it is a 22 ohm resistor and the 2nd band color has been altered by heat and was originally red (the photo is not great and it seems the resistor is somewhat damaged). \$\endgroup\$
    – Lorenzo Donati support Ukraine
    Jun 11, 2019 at 12:34
  • \$\begingroup\$ @LorenzoDonati Good point...I don't think I've ever seen a 23Ω resistor! \$\endgroup\$
    – evildemonic
    Jun 11, 2019 at 14:31
  • \$\begingroup\$ Careful: last BLK band may also mean TemperatureCoefficient=250PPM \$\endgroup\$
    – quetzalcoatl
    Mar 9, 2021 at 12:46

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