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Electronics => Beginners => Topic started by: gis on November 13, 2013, 11:59:33 am

Title: Guess who - broken component photo
Post by: gis on November 13, 2013, 11:59:33 am
Can anybody guess what is this and its value from dimensions?

Thanks, cheers
Giovanni
Title: Re: Guess who - broken component photo
Post by: Dataforensics on November 13, 2013, 12:21:42 pm
I assume its open circuit. If so you could try and carefully unwind the wire thats left. Then measure resistance of what you can and calculate for whole length.

Would have thought that even if damage has caused a change in value, you would get magnitude, and you have first two digits.

Title: Re: Guess who - broken component photo
Post by: gis on November 13, 2013, 12:29:18 pm
Thanks a lot!
Title: Re: Guess who - broken component photo
Post by: dr_p on November 13, 2013, 01:40:43 pm

that looks like heat damage on a 2W package, so I spit the table bellow:

Code: [Select]
	5 V	10 V	20 V	30 V	40 V	50 V	100 V	200 V
22      1.1 W	4.5 W	18.2 W	40.9 W	......	......	......	......
220	0.1 W	0.5 W	1.8 W	4.1 W	7.3 W	11.4 W	45.5 W	......
2k2	......	......	0.2 W	0.4 W	0.7 W	1.1 W	4.5 W	18.2 W
22k	......	......	......	......	0.1 W	0.1 W	0.5 W	1.8 W



what voltage was used in the device it came from?
Title: Re: Guess who - broken component photo
Post by: G7PSK on November 13, 2013, 06:36:42 pm
It does not look like it says 2k2 or 2.2 so you can most likely strike that one, I would bet on 22 or 220 ohms as the most probable judging by the wire thickness.
Title: Re: Guess who - broken component photo
Post by: SeanB on November 13, 2013, 07:45:38 pm
If you do not want to unwind just measure from half way to whichever end is still intact. As it is 22R or 220R you simply have to see if the resistance to the end is under 15R or under 70R. With the thick wire my guess is it is a 22R 2W glazed enamel resistor. Replace with a 22R 5W one and you will be fine.

I will guess it came out of a telephone, as this is a common size and type used there.