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Cjlennon623
Nov 1, 2008, 01:03 PM
Hey Folks,
Got a quick question for the electronic component experts out there. I have a light blue ceramic resistor (I believe it is a resistor! It looks like one.) I took off a damaged circuit board and I'm trying to figure out some things about it. It has a marking of "102 J" on it and it is about the size of a 1/2 watt carbon resistor but no stripes that indicate ohms. Just the "102 J" marking, much like you may see on a disk capasitor. Here are the questions:

1.) What does the 102 J marking indicate? By the way, it reads exactly 1.0K Ohms using a digital ohm meter. Could it stand for 1.02 ohms? If so, why the "J"?

2.) Why ceramic? What's the purpose of using a ceramic resistor instead the traditional carbon resistor?

As always, thanks so much for the education. I always put it to good use!

Chris

Stratmando
Nov 3, 2008, 06:12 AM
Here's some info:
NRC1206-102J NIC RESISTOR (http://www.searchlighttech.com/searchResults.cfm?part=NRC1206%2D102J)

Resistor - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Resistors)

DanielF
Nov 27, 2008, 04:17 PM
For capacitors and (surface-mount) resistors, the three digits are:
First digit of value
Second digit of value
Number of zeroes following value digits.
Thus '102' is 1000 ohms, exactly as you measured. (For capacitors, the value is in pF.)
The 'J' appears to be a tolerance code (5%).
The resistor element won't be ceramic (more likely carbon or metal film). You're perhaps confusing the outer insulation coating with the same stuff used on ceramic capacitors.

Cjlennon623
Nov 27, 2008, 08:01 PM
DanielF,
Thank you for the reply. I got no response until yours. Hope things are well with you. Best wishes!

Chris

Stratmando
Nov 28, 2008, 06:51 AM
Cjl, I understand you had a problem getting to the link from Wikepedia.
J IS 5 %.
I could have shortened it, If you are very interested, that is where you want to start.