Author Topic: Non-standard resistor value?  (Read 1732 times)

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Offline overlordMannyTopic starter

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Non-standard resistor value?
« on: February 14, 2019, 03:53:00 am »
Hi everyone. I'm a bit of a noob. Even though I've been formally trained in electronics by the USAF it's been many, many years since I've done much electronics repair work.

I have an old Nintendo 64 power supply that's giving me no output at all. I'm not terribly familiar with switch mode power supplies, but from what I can understand it looks like I may have an open somewhere on the primary side( no fuses blown). I found a resistor that seems to be reading high at 68.2M ohms. When I look up the color code, (blue, grey, green, gold, green), it looks like it should be 68.5 ohms at .5% tolerance, which is apparently non-standard. Looking at the numerical values, they seem too close to be a coincidence. What am I missing/not understanding. Here's a picture...
« Last Edit: February 14, 2019, 03:24:02 pm by overlordManny »
 

Offline tooki

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Re: Non-standard resistor value?
« Reply #1 on: February 14, 2019, 04:09:56 am »
Could it be a fusible resistor that uses a nonstandard color code, at least for some of the bands? (I think there was a discussion of those on here a few months ago.)
 
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Offline golden_labels

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Re: Non-standard resistor value?
« Reply #2 on: February 14, 2019, 04:14:12 am »
digit1 | digit2 | multiplier | tolerance | temperature coefficient?
That would be: 6.8MΩ, 5%, 20mmp/K.
People imagine AI as T1000. What we got so far is glorified T9.
 
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Offline overlordMannyTopic starter

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Re: Non-standard resistor value?
« Reply #3 on: February 14, 2019, 04:27:53 am »
digit1 | digit2 | multiplier | tolerance | temperature coefficient?
That would be: 6.8MΩ, 5%, 20mmp/K.
That correct! I just found this on allaboutcircuits, amazing how you find answers after you post questions.

"Color Code Exceptions
5 Band Resistor with a 4th Band of Gold or Silver

Five band resistors with a fourth band of silver or gold form an exception, and are utilized on specific or older resistors. The first two bands represent the significant digits, the third band is a multiplication factor, the fourth band is for tolerance and the fifth band is for the temperature coefficient (ppm/K)."

Guess that's not my power supply problem. haha The search continues.
 


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