According to the chart (unless im reading it wrong) the below resistor should be 4.7K?

But when i test with my multi meter its more like 47 Ohms......

Am i missing something?

Thanks

 

yellow -purple-red-silver should definitely be a 4.7kΩ 10% resistor.

yellow-purple-black would be 47Ω

Maybe it is a 4.7mH 10% inductor?

 

I'm with MrChips on this- it's either mismarked, or an axial inductor (based on body color).... I tried to mentally _see_ that 3rd band as black and couldn't do it. I could see it as red, as brown... but not black, so...

 

I think it's an Inductor... 4700uH 10%


https://www.vishay.com/inductors/color-code-calculator/

 

I'm with MrChips on this- it's either mismarked, or an axial inductor (based on body color).... I tried to mentally _see_ that 3rd band as black and couldn't do it. I could see it as red, as brown... but not black, so...

Its definitely red....

Whats an axial inductor???

 

I think it's an Inductor... 4700uH


https://www.vishay.com/inductors/color-code-calculator/

sorry posted before i saw your post....

Thanks

 

Just had another look at the board and its marked as L2 - so definitely an inductor.

 

axial inductor- what you have -- axial usually has 2 leads as an axis. It isn't a can or a toroid.

 

Is it old or in a harsh environment? The top lead looks quite pitted. Unless that was your tool marks from pulling it off of the board.

 

Is it old or in a harsh environment? The top lead looks quite pitted. Unless that was your tool marks from pulling it off of the board.

Its fairly old but i think its a trick of the camera as it doesn't look so bad in the flesh!

 

Don't know about anyone else, but I see Yellow, Purple, Black (470) That makes a 47 ohm resistor in my mind. 10% means it could be anywhere from 42.3 ohms to 51.7 ohms.

Inductor? My guess is - no. Not an inductor. I have seen wire wound resistors, and when they're wrapped in one direction only then they act like inductors, where as when they're wrapped in both directions the inductance cancel's out each other.

Wire wound resistors are typically longer, and if I'm not mistaken, they're lower resistance than 47 ohms. But I suppose you could have a 47 ohm wire wound. Or maybe it's an inductor. Without being able to put my hands on it - can't tell.

As for the third color band, I see back. But I have a hard time with red and green. Red/Green deficient. And here, I've made a living in electronics inspection. That's why I LOVE numbered resistors. But I see black. Not red.

[edit] OK, now I'm looking at this on a different computer monitor. Now it looks burgundy red. But I'm still going with black.

 

Don't know about anyone else, but I see Yellow, Purple, Black (470) That makes a 47 ohm resistor in my mind. 10% means it could be anywhere from 42.3 ohms to 51.7 ohms.

Inductor? My guess is - no. Not an inductor. I have seen wire wound resistors, and when they're wrapped in one direction only then they act like inductors, where as when they're wrapped in both directions the inductance cancel's out each other.

Wire wound resistors are typically longer, and if I'm not mistaken, they're lower resistance than 47 ohms. But I suppose you could have a 47 ohm wire wound. Or maybe it's an inductor. Without being able to put my hands on it - can't tell.

As for the third color band, I see back. But I have a hard time with red and green. Red/Green deficient. And here, I've made a living in electronics inspection. That's why I LOVE numbered resistors. But I see black. Not red.

It’s 100% red

 

Looks like Yellow, purple/violet, red, silver to me.

 

Can you rig up a simple LR and look at the time constant to see if it's an inductor?

 

Can you rig up a simple LR and look at the time constant to see if it's an inductor?

What’s an LR?

 

I think it has already been confirmed as 4.7mH inductor. The designation on the board is L2.

 

Look at my edit. Different screen, I see dark dark red.

Someone said it's designated as L2. Well, I don't see any boards in any of the pictures so - - - .

 

What’s an LR?

It's just a simple circuit with an inductor (L) in series with a resistor (R). When a step voltage is applied (a voltage source turned on), the current rises from zero to its final value exponentially with what is known as a "time constant". For and LR circuit the time constant is L/R. Since you have measured the DC resistance to be about 50 Ω, if that's the R then if it is a 4.7 mH inductor the time constant would be about 0.1 ms. So if you could hook that up to a signal generator producing a square wave at something like 1 kHz (which can be done with a 555 timer pretty easily), then if you could look at the current in the circuit (using a small current-sensing) resistor on an oscilloscope you could determine the time constant and see if it is consistent with it being a 4.7 mH inductor.

Now, I suspect you don't have the one key piece of equipment you would need -- the scope. There are other ways to get an estimate of the answer without it, but they are probably more hassle than they are worth for you.

 

I think it has already been confirmed as 4.7mH inductor. The designation on the board is L2.

View attachment 143832

Agreed.

 

Hello,

Have a look here for an inductor color code:
http://www.instructables.com/id/Inductor-Color-Code-Guide/

Bertus