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How to added up a Resistor Value using misc values

CocaCola

Apr 7, 2012
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Use this one, try to get to 100Ω...
Start with a 98Ω for R1...

http://www.1728.org/resistrs.htm

Let me know what value you need to use for R2 to get to 100 :cool:

Hint start at 99999999999Ω :p for R2 and go up from there...
 
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danny davis

May 9, 2012
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well the tech at work did this one

47.5K in parallel with 69.8K = 1.87K

15.8K in parallel with 1.96K = 1.74K

He didn't choose one step higher like a 2K resistor for RT

How do u explain this?
 

KJ6EAD

Aug 13, 2011
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He's choosing values from the E96 series to make an E48 value in one case and an E96 value in the other. Since this is clearly an academic exercise, his choice for the first value may be random or he may be working from a selected subset of values that's not known to us.

As previously stated, his solution as you've presented it for 1.87k is wrong. 47.5k in parallel with 69.8k yields 28.265k, not 1.87k.

The correct approach is to double 1.87k (3.74k) and use 2 3.74k resistors in parallel for an exact match. The same method works for 1.74k made from 2 3.48k's.

Back in post #33 I presented the nearest parallel match for 1.87k using E24 values. In the E24 series, 3.6k and 3.9k are the nearest to 3.74k, one higher and one lower.
 
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danny davis

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1.78K, 1.87K, 1.91K, 1.74K are from an E48 series?

47.5K, 69.8K, 15.8K are from a E96 series?

15.8K in parallel with 1.96K = 1.74K

See how its mixed E96 series with an E48 series to make an E48 RT

The Tech was mixing E series right?
 

KJ6EAD

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You can look at the chart to see which series a value is from. What seemed less practical and more academic to me was the use of two E96 values to create an E48 value. If you already had a complete set of E96 values, there'd be no need and in practice it's more common to combine values from a lower series to create a value that may exist in a higher series, not the other way around.
 

danny davis

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the use of two E96 values to create an E48 value

When you do it this way , how do u know which is the starting point? do u choose a higher value or lower value than RT?

When you use 2 E48 values to make a E96 value, do u choose a higher or lower value than RT?
'
 

CocaCola

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When you do it this way , how do u know which is the starting point?

FOR THE LAST TIME, JUST PICK A STARTING POINT, THERE IS NO RIGHT OR WRONG WAY OR VALUE, JUST PICK ONE AND WORK THE MATH TO GET THE OTHER VALUE, OK? IF it doesn't work pick another value and try again...
 

danny davis

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Here is the list of resistors that i'm confused on the package numbers

20ohms is 20RO
29.9 ohms is 29R9
11 ohms is 11R0
150 ohms is 151
54.9 ohms is 54R9
301 ohms is 3010
63.4 ohms is 63R4
100 ohms is 101
30.1 ohms is 30R1
200 ohms is 201
14.7 ohms is 14R7
3.32K is 3321
23.2K is 2321
3.01K is 3011
69.8K is 69R8
15.8K is 1582
22.1K is 2212
210 ohm is 2100
820 0hm is 821
1.5K is 152
2K is 2001
698K is 6983
16.2K is 1622
523 ohm is 5230
110 ohm is 1100
4.02K is 4021
47.5K is 4752
24.9ohm is 24R9
1.87K is 1871
1.96K is 1961
21.0K is 2102
6.81M is 6184
8.25M is 8254
4.02M is 4024
6.19M
3 m
2.21M 2214
5.1M 5104
355.5K is 3573

R52 2322 23.2k

R54 1783 178k

R53 3321 3.32k

R38 2150 215 OHM

R29 8250 825 OHMS

R35 2214 2.21M

R20 3480 348 ohm

R17 272 2.70K
 
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davenn

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where specifically is the confusion ?
thats all pretty standard

Dave
 

danny davis

May 9, 2012
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23.2K is 2321

How do u know its 23.3K and not 2.33K?

3.01K is 3011

How do u know it's 3.01K and not or 30.1K?

15.8K is 1582

How do u know it's 15.8K and not 1.58K?

22.1K is 2212

How do u know its 22.1K and not 2.21K?

23.2k is 2322

How do u know its 23.2K and not 2.32K?

4.02K is 4021

How do u know its 4.02K and not 40.2K?

47.5K is 4752

How do u know its 47.5K and not 4.75K?

16.2K is 1622

how do u know it's 16.2K and not 1.62K?
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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For these, last digit is the number of zeros.

23.2K is 2321

How do u know its 23.3K and not 2.33K?

Check again. that should be 2322

232 00

3.01K is 3011

How do u know it's 3.01K and not or 30.1K?

301 0

15.8K is 1582

How do u know it's 15.8K and not 1.58K?

158 00

22.1K is 2212

How do u know its 22.1K and not 2.21K?

221 00

23.2k is 2322

How do u know its 23.2K and not 2.32K?

232 00

etc..
 

CocaCola

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23.2K is 2321

How do u know its 23.3K and not 2.33K?

Neither 2321 is 2.32K

232 x 10¹ (aka 10) 2321

or

23.2K is 2322 or 232 x 10² (aka 100)

3.01K is 3011

How do u know it's 3.01K and not or 30.1K?

301 x 10¹ (aka 10) is 3010 or 3.01K

15.8K is 1582

How do u know it's 15.8K and not 1.58K?

158 x 10² (aka 100) is 15800 or 15.8K

See the obvious pattern? First three digits are the significant digits and the 4th is the multiplier aka power of 10...
 

danny davis

May 9, 2012
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no, The numbers on the resistors package are these values
Thats why it doesn't make sense to me cause i get confused

23.2K is 2321
3.01K is 3011
69.8K is 69R8
15.8K is 1582
22.1K is 2212
23.2k is 2322
4.02K is 4021
47.5K is 4752
16.2K is 1622
 

danny davis

May 9, 2012
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I think the techs at my work mixed them all up with the bags and numbers thats why i'm confused maybe
 

CocaCola

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no, The numbers on the resistors package are these values
Thats why it doesn't make sense to me cause i get confused

23.2K is 2321
3.01K is 3011
69.8K is 69R8
15.8K is 1582
22.1K is 2212
23.2k is 2322
4.02K is 4021
47.5K is 4752
16.2K is 1622

What do you mean "no"? You just had 2 people explain it to you and you still argue and come back with "no"?

YES!
 

danny davis

May 9, 2012
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These package numbers are all wrong i think that what was confusing me someone labeled them wrong and put the resistors in the wrong bags and even on the schematics

23.2K is 2321
3.01K is 3011
69.8K is 69R8
15.8K is 1582
22.1K is 2212
23.2k is 2322
4.02K is 4021
47.5K is 4752
16.2K is 1622
 

CocaCola

Apr 7, 2012
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These package numbers are all wrong i think that what was confusing me someone labeled them wrong and put the resistors in the wrong bags and even on the schematics

NOPE! Only the first one is wrong...

"23.2K is 2321" = incorrect it should be 23.2K is 2322

The rest are perfectly CORRECT!
 
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