# 3,9k and 3k9 resistance - are the same?

Discussion in 'Electronic Basics' started by Pfrogs, Jul 23, 2003.

1. ### PfrogsGuest

Hi,

this might seem a stupid question, but I need a 3,9k resistance but I can
only find at the on-line store a 3k9 resistance. Are they the same? I'm
asking this cause I also need a 4,7k resistance and the reference, at the
on-line store, is actually 4,7k.
If they are the same why do they sometimes use decimal notation and other
times use the ?k? notation?
Regards,

Pfrogs

2. ### John LarkinGuest

What you really want is a 3.9k resistor.

John

3. ### John PopelishGuest

I don't have any idea why this place sometimes uses a decimal point
and sometimes not, but a 3k9 resistor is certainly a 3900 ohm
resistor. On schematics (that might get photocopied or scanned)
decimal points can get lost or ignored in the noise, so the k as
decimal point notation was adopted by many as a more reliable way to
graphically record a decimal point.

4. ### WongGuest

Hi,
Easy for lazy peoples to speak ?
4.7K and 4K7 ??
^

5. ### cpemmaGuest

All over Europe. As an aside, I've just used some caps marked 222k.

Now that must be 2 - 2 - 2 zeroes - 3 zeroes. 2200000. Quite a mouthful for
a tiny cap.

It would be far clearer to mark them 2n2.

6. ### Costas VlachosGuest

Are you sure the "k" means 3 zeros in this case? If so, wouldn't that make
it a 2.2uF? My guess is that it's simply a 222 cap (2n2) and the "k" has to
do with something else (type of dielectric perhaps?).

Costas

7. ### John PopelishGuest

The K means 10% tolerance. It is a 2n2 (2200 pf).

See:
http://www.twysted-pair.com/capidcds.htm

8. ### Keith WoottenGuest

Over a longer period, I'd say that 'four kay seven' was rather more
commonly heard than 'four point seven kay'. I'm in the yoo kay.

As well as the often made point about decimal points getting lost on
copies, there's also the issue with many Yerpeens (not in the UK) using
a comma as the decimal separator.

Cheers