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ceramic capacitors + my mother
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ceramic capacitors + my mother

by sigflup on Sun Apr 04, 2010 3:27 pm

What's the difference between a ceramic capacitor that reads "330" and one that reads "331" ?

Also, I'm assuming a capacitor that reads 222 is 2.2nf- is this correct?

thanks much in advance.
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Re: ceramic capacitors + my mother

by johngineer on Sun Apr 04, 2010 4:43 pm

My mother (i.e. Google) says:

http://www.google.com/#hl=en&source=hp& ... ecf4f91972

hey, it's right at the top.
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Re: ceramic capacitors + my mother

by sigflup on Sun Apr 04, 2010 5:09 pm

Ok- is there a difference between 330 and 331? I've seen both
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Re: ceramic capacitors + my mother

by johngineer on Sun Apr 04, 2010 6:19 pm

sigflup wrote:Ok- is there a difference between 330 and 331? I've seen both


yes. if you read the first link that comes up for that google search it explains the numbers and what they mean.

warning: you may be required to do some math.
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Re: ceramic capacitors + my mother

by zener on Sun Apr 04, 2010 6:27 pm

My advice is learn uF and pF and forget about nF!

330 = 33 pF
331 = 330 pF
332 = 3300 pF = .0033uF
333 = 33000 pF = .033 uF
334 = 330000 pF = .33 uF

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Re: ceramic capacitors + my mother

by sigflup on Sun Apr 04, 2010 7:58 pm

huh, ok- thanks for the advice. The confusion for me come from this board that I'm looking at that has silk-screened in white 330pf next to the capacitor. It had a ceramic one labeled 330 (accidentally chiped in in half) . All I have to replace it is a 331 labeled capacitor. I guess I'll also look for a 33pf capacitor and try both
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Re: ceramic capacitors + my mother

by westfw on Sun Apr 04, 2010 8:19 pm

A capacitor labeled "331" is almost certainly 330pF (33 plus one 0.)
A capacitor labeled "330" you can never be sure about :-(
I would expect that a board labeled "330pF" would want 330 pF, and not necessarily one marked "330"
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Re: ceramic capacitors + my mother

by minerva on Mon Apr 05, 2010 3:46 am

"331" definately means 330 pF (33 x 10^1 pF).

"330" is a bit ambiguous. Ceramic capacitors of 100 pF or less causality just have their value printed straight on them, for example, a 22 pF capacitor will just say "22".

Is your "330" cap 330 pF, or is it (33 x 10^0 pF) ? To be honest, I can't really tell you.

If you've got access to a meter that supports capacitance measurement, I suggest you measure it.
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Re: ceramic capacitors + my mother

by John_NY on Thu Apr 08, 2010 7:18 pm

A meter helps.
Having a capacitance meter has definitely helped me nail down the correct order of magnitude of various capacitors. I picked up a cheap-o yellow meter for $15 (from a Chinese eBay vendor) -- it has a manual dial to help set the "zero" value. For $15 you get what you pay for -- it's not too good at measuring at the 1pF (or even 10pF) range, but it is better than no estimate at all. A low-end capacitance meter was a welcome addition to my very amateur electronics setup.
my 2¢,
-John
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