Electronics experts - what is this?

If it is a resistor, then J indicates that it's 5% tolerance and also acts as the decimal point. So it would be a 5W, 5%, 33 Ohm resistor. But I want to see R?? clearly next to it on the silkscreen print to be sure it's a resistor.
 
I remember electronics in school.

I got caught lying with my head on my desk not paying a bit of attention whatsoever in year 9.

"Have you listened to a word I've been saying!"
"...Yes.", a lie.
"OK then, what's this component", He points to the board, there's a symbol drawn on it.
"That's a Light Emitting Diode sir."
"Oh, it seems you were listening."

I was already past GCSE knowledge by this point, so I was no stranger to the symbol for an LED. The school never ran GCSE electronics, not enough people wanted to do it. This means I also didn't take it at A-Level.

I'm now taking a break from writing my final year project for a B.Eng honours degree in electronics.
 
flux capacitor :D

ok so i spot two damaged parts bit is the white one working or it that just the casing thats damaged ?
 
R is often used to denote the decimal place when noting resistor values, like 4R7 would be 4.7Ohms. Sometimes you use a K instead if we're talking several thousand Ohms, so 4K7 is 4,700Ohms.

R33 to me implies 0.33Ohms, but you'd need to check that (must multimeters have a resistance mode) - as said above, lift one end first or you might get some other resistance value which goes down some other track on the PCB.

J is most likely to be the tolerance - K, J and F are common ones (+/- 10%, 5% and 1% respectively).

The only thing putting me off is the little symbol on top, but it could just be some manufacturer logo I suppose.
 
sara said:
R is often used to denote the decimal place when noting resistor values, like 4R7 would be 4.7Ohms. Sometimes you use a K instead if we're talking several thousand Ohms, so 4K7 is 4,700Ohms.

R33 to me implies 0.33Ohms, but you'd need to check that (must multimeters have a resistance mode) - as said above, lift one end first or you might get some other resistance value which goes down some other track on the PCB.

J is most likely to be the tolerance - K, J and F are common ones (+/- 10%, 5% and 1% respectively).

The only thing putting me off is the little symbol on top, but it could just be some manufacturer logo I suppose.
Click to expand...

This.

The Infinity symbol is the manufacturers mark.
The R is used to denote the decimal point, as a decimal point itself can often be misinterpreted. Its a WireWound resistor. The J does indeed point to the tolerance.
If you intend to measure the resistance, don't forget to measure the resistance of the probes you are using too! Especially when talking about such a low resistance.

The worrying little bit is the resistor also identified as having burned out! That looks like a 1.4W resistor, but you will need some detective work to find out what it was. If its a dual channel amp, then check the other channel for that value (assuming its both an amp and dual channel!)
 
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