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Old 12-24-2010, 12:37 PM   #1
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Can I use 100 ohm instead of 270ohm without problem for spark out on ms2 build?
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Old 12-24-2010, 01:19 PM   #2
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Yes, but use a 1/2W resistor because you're pulling 50mA (=1/4W) through it.
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Old 12-24-2010, 01:25 PM   #3
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I wouldn't quite say that 50mW are 1/4W. More like 1/16W, a bit less even. So he's fine with 1/4W.
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Old 12-24-2010, 01:30 PM   #4
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50mA @ ~5V
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Old 12-24-2010, 01:40 PM   #5
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Old 12-24-2010, 01:42 PM   #6
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I used 1\2 watts anyways, cause its what I have on hand.
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Old 12-24-2010, 02:20 PM   #7
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Quote:
Originally Posted by Techsalvager View Post
Can I use 100 ohm instead of 270ohm without problem for spark out on ms2 build?
Yes.

5v through 100 ohms is 50ma, which is 0.25 watts. So a 1/4 watt resistor will do. It'll generate some heat, but it'll be fine. A 1/2 watt part won't even notice.
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Old 12-24-2010, 06:35 PM   #8
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We use 100 ohm pullups in the PNPs. Some of the newer hotter coils prefer lots of pullup. Pretty sure they're all 1/4 watt.
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Old 12-24-2010, 06:55 PM   #9
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what's the advantage of more pullup?
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Old 12-24-2010, 07:18 PM   #10
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If your coils fire, then likely none.
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Old 12-24-2010, 07:20 PM   #11
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They don't when it's really cold out...
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