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Weird resistor color code

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ZASto

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Hi,
in one SMPS I found blown resistor with the following color code:
Yellow (4)
Violet (7)
Gold (???)
Gold
Black.

Can not figure out the value :(
Dimensions of the resistor are as standard MF0207 metal film.

I guess that it is fusible resistor, placed in series with primary of the ferrite transformer, on the other side of primary is TinySwitch TNY268.
WTF is resistor in primary?
 

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Thanks Brian, That's what I suspected.
But, to your knowledge, is there any "calculator" for this kind of marking? I have no problems with ordinary 4/5/6 band resistors, (memorised color values 40+ years ago :))
 

(memorised color values 40+ years ago :))
50+ years ago for me :confused:

It seems to follow the standard 'two digits plus multiplier' sequence (4, 7, * 0.1) with the second gold band being 5% tolerance. The final band might mean fusible or hi-stability, there are inconsistencies between manufacturers. 4.7 Ohms would seem the right kind of value to use as an inrush limiter/fuse in your application.

Brian.
 

Hi,



for me the first band looks to be green, but I might be wrong.

I usually use the calculator provided by Digikey [1], but there it is not possible to select gold as 3rd band and black as 5th band.

[1] https://www.digikey.com/en/resource...ors/conversion-calculator-resistor-color-code

BR
I do not need to use calculators for resistors :)

To you first band may look green, photo was taken under LED "natural white" light, but, you know, white LEDs do not have full color spectrum. It is YELLOW :), trust me.

Anyway, thanks for pointing to a calculator, some youngsters might find it useful.
 

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