[sdiy] Capacitor Values

[Magnus Danielson]

From: GothGeek Sysadmin <xyzzy at sysabend.org>
Subject: [sdiy] Capacitor Values
Date: Thu, 21 Feb 2002 04:31:13 -0800

> Ok. I feel like a real idiot asking this but I've gotta...
> 
> Circuit I'm ordering parts for calls for some Polyester caps and
> gives the values 1000n  100n and 10n
> 
> Am I right that this is nanofarads?  ie : 1000n = 1uf ?

Indeed.

Just to be explicit about it, when it comes to resistors, caps and
inductors, the unit is commonly assumed to be Ohm, Farad and Hendry
respectively. It is just a industry short-hand.

Another thing is that people does not use the SI prefixes and their
associated rules as they should. Early out there where only the mili
and micro units, so when you wanted to write 10 pF you wrote it 10 uuF.
Then it seems that the pico unit stuck but not the nano, so you can
still see a lot of 4700 pF where it should say a 4.7 nF. For
electrolytic caps we also see these horrible 47000 uF things when it
really should say 47 mF.

BTW. If you want to have the SI document, go to NIST and download the
PDF (for free!) as Special Publication 330. They also have a related
document on the use of SI units, which could be recommended reading if
a reminder is in place.

> I feel so stupid asking this I'm not even gonna bring up my LFO questions
> for the night.  Hrm, or rather its suddenly morning I see and perhaps
> that is my problem.

Don't be afraid to ask... the insight of onces limited understanding
is the first step to increase said understanding.

> Thanks in advance!

Anytime!

Cheers,
Magnus