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Resistor Designations 4M7?


 
5/30/2000 3:57 PM
jimi
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Resistor Designations 4M7?
I recently ran across resistor designations like these; 4M7 4k7 6k8 1k5 does anyone know the values of these resistors? Thanks
 
5/30/2000 4:12 PM
zachary vex
sure, it's a shortcut for 4.7M, 4.7k, 6.8k, and 1.5k.  
 
there are more confusing methods for referring to values on resistors, pots, and caps. one is to use a hybrid colorcode reference that looks like three digits...  
 
104 is 100k for a resistor or 100,000 pF (.1 uF) for a cap. that's broken down like this... the one and zero are digits in the final value, the 4 is the number of zeros following those digits.  
 
likewise, 333 would be 33k for a resistor/pot, or 33,000 pF (.033 uF) for a cap. that's three-three-and three zeros after.  
 
confusing ones? 100, which is 10 ohms or 10 pF, because it's one-zero-and no zeros after. or 101, which converts to 100 ohms or 100 pF, because it's one-zero-and one zero after. the worst part is that on the very tiniest components like monolythic caps and surface-mount parts, you find these weird numbers printed in tan-on-tan and silver-on-black. it's a real squinter.  
 
zachary
 
5/30/2000 4:13 PM
Eric H
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quote:
"I recently ran across resistor designations like these; 4M7 4k7 6k8 1k5 does anyone know the values of these resistors? Thanks  
"
 
 
I believe these are European designators. Anyway, if you move the letter to the end, and replace it with a decimal point, you're in. Easier to show, than explain: 4M7 is 4.7M(meg-ohm), 6k8 is 6.8k (k-ohm).  
 
-Eric
 
5/30/2000 5:28 PM
EFX
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Here's a couple more of the International designations that you may see. 22R is 22 ohms and R22 is 0.22 ohms.  
 
EFX
 
5/30/2000 11:43 PM
Pete
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As everyone else said, it's just in place of a decimal point (i.e 4M7 = 4.7M)  
 
The reason that it's written this way is because when circuits are photocopied a lot, decimal points can disappear or start to appear  
Eg if you had say a 168 ohm resistor (if there was one), the 6 might start looking like a decimal point. So if it were to meant to be a decimal it would look like 1K8 instead.  
 
Pete
 
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