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Crazy resistor! Help me id it

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bulak

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**broken link removed**

Just got this defective resistor out of my tv set and it's very weird. Look at those colors, it got gold on the 2nd stripe and possibly gray(?) on the 4th stripe. How is that possible, can someone tell me what is the value of this thing?

Thank you.
 
No, I don't think so. The 2nd stripe is gold (what puzzles me).

There is a better pic here, if you see at the bottom right it is there:

**broken link removed**
**broken link removed**

Looking at this picture it seems it is green - gold - red - white or gray - silver which doesn't make sense.
 
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Reverse engineer what it's connected too. That might give a hint.

My guess; GREEN BROWN RED (TEMPERATURE COEFFICIENT) or 512 10%; Haven't done the math for trmpco.

See here: **broken link removed**
 
Supposing the 2nd stripe is brown (that doesn't look any brown in close up view, much more like gold), that still doesn't explain the 4th stripe which is gray or white (the 4th stripe can't be higher than 4) and the article you have linked says that only 6-band resistors have temperature coefficient.

And it's connected to dozens of things, I ain't got the expertise to deduce that :(
 
I notice it's got a warning triangle next to it. Could the strange coding be to do with safety spec's?

Looks like it's on a fairly simple bit of board - shouldn't be too hard to trace the immediate circuit. You just need to be very patient.

First stripe looks green in the original main photo, but blue in the photo of the circuit board. Maybe it's supposed to be black?
 
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What if you're looking at it backwards, and that last stripe is actually white? That would make it white-gray-red-gold-green, which is 98.2 ohms 5% tolerance.

It definitely looks silver to me, but perhaps it's a shiny white....
 
It's definitely a fusible resistor, of a low ohmic value used in series with the main PSU rail.

It appears to me to be grey red (ie 82) and gold third bad would indicate /10 so that would be a fairly typical value of 8.2 ohms. The silver will be tolerance and the green is unusual for sure but since the main property of this resistor (after resistance) is fusability so the green might indicate something to do with that, ie wattage. It looks about the right size compared to the 2W fusibles I stock so I guess it's a 2W fusible.

A green band might indicate a 5W fusible but I just don't see it being big enough to meet that.

Did anybody ask "what resistance value does it measure"? :)
 
This resistor appears to be part of the PFC (power factor controller) circuit. You could do a google search for the datasheet of the ic associated with this resistor which may have an application circuit or search for the service manual of the tv which may have the psu schematic.

Timescope
 
Could either be a fuse or a NTC inrush current limiter. On the board it is labled R6 so my guess is a NTC thermistor. What does it measure? Looks like there is a place for a jumper next to it?
 
Thanks everybody.

It's measuring 0.4ohms and I assume it is in short (?).

@ronv Yes, there is a jumper next to it.
 
Thanks everybody.

It's measuring 0.4ohms and I assume it is in short (?)..

Are you measuring it in circuit or out of circuit?

You should always measure it out of circuit to get an accurate reading, as it prevents the resistance of the rest of the circuit from interfering.
 
Are you measuring it in circuit or out of circuit?

You should always measure it out of circuit to get an accurate reading, as it prevents the resistance of the rest of the circuit from interfering.

Out of circuit, just like the first picture.

The problem is a need to buy a new one but it is reading 0.4ohms (I'm assuming it's in short) and I don't know which should I buy.

@throbscottle It's looking black there but I think it's just the shadow and perspective of the photo.
 
Out of circuit, just like the first picture.

The problem is a need to buy a new one but it is reading 0.4ohms (I'm assuming it's in short) and I don't know which should I buy.

I see the predicament....

I wish you the best of luck! Have you tried finding a schematic diagram for your TV (repair manual, perhaps)?
 
No matter which it is I doubt it is your problem. Take a couple of voltage measurements on both ac and dc on both sides of the diodes right above it. then measure on both sides of it.

PS Did you check the fuse?
 
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I don't think that I have ever seen a resistor fail short.

I think the best way to proceed is to try to find a schematic, or reverse engineer one if necessary. From that we may be able to figure out what it's purpose in the circuit is.
 
@DerStrom8 Thanks. I found the service manual here https://elektrotanya.com/philips_32pfl5605d_78_6605d_78_led-tv.pdf/download.html but I couldn't extract any useful info about this resistor.

@ronv The TV is working but no sound in the speakers and line out. The fuse is fine.

@ChrisP58 I looked at the schematics but didn't find this resistor there. I don't think it is there. All I know there was a zener diode 6v8 in short (the one almost in the middle, between the blue resistors in the 2nd picture, which is connected to this resistor) and the resistor with the weird stripes.
 
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@DerStrom8 Yes, but this resistor isn't mentioned there. I suspect the amplifier system is not getting power somehow.

@ronv You mean to measure them off circuit or with the power on?

@moderator Initially this conversation was supposed to id a resistor! But feel free if you want to move it to the repair section.
 
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