Unidentified Resistor Value - Potentially Missing Band

Thread Starter

Ri5ux

Joined Sep 5, 2017
42
Hey guys! I'm new here, but I'm repairing a power supply that short-circuits to ground during a power-up attempt, and I came across this resistor. The circuit board around the resistor looked like it got pretty hot. I removed the resistor, and powered up the power supply, and it started right up with no problems. I'm now looking for a replacement resistor, but I can't identify this resistor. It looks like one of the bands may be missing. It measured around 70-75 ohms, though I originally thought it should be 20 ohms, due to the color coding. I feel as though I may be missing something, and any help is greatly appreciated! (Image of resistor is attached)
 

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AlbertHall

Joined Jun 4, 2014
10,258
What colour are the bands you can see?
The photo may distort the colours a bit. The left hand band on the photo could be either red or violet. The right hand side two look like black or grey and silver or gold.
 

Thread Starter

Ri5ux

Joined Sep 5, 2017
42
It's pretty hard to tell what the left band is due to the green coating on the resistor. It looks to be either brown or violet like you said, but if it's violet, it hardly has any saturation to it.

My best guess is brown, black, gold. (Though violet, black, gold would make sense since the result is 79 Ohms and the multi-meter measures close to that.)
 

AlbertHall

Joined Jun 4, 2014
10,258
Ok. It doesn't look like that resistor got hot though. There is no discolouration of that green coating.
Brown: 10, 12, 15 or 18 ohms.
Red: 20, 22, or 27 ohms.
Violet: 75 ohms.

If it measures near 75 ohms that's probably what it is (and is undamaged!).
 

Thread Starter

Ri5ux

Joined Sep 5, 2017
42
Ok. It doesn't look like that resistor got hot though. There is no discolouration of that green coating.
Brown: 10, 12, 15 or 18 ohms.
Red: 20, 22, or 27 ohms.
Violet: 75 ohms.

If it measures near 75 ohms that's probably what it is (and is undamaged!).
Good point, I'll check the rest of the power supplies' circuit. Thanks for the help!
 

Thread Starter

Ri5ux

Joined Sep 5, 2017
42
Odd, I soldered the resistor back in, and the power supply worked. Must have just been a poor solder joint... o_O
 
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