Reading Capacitor Codes

[Kevin_L]

Hi, im new to this forum as well as pedal building.

I am currently about to start the Tweak-O tutorial, but i have chosen to buy my own parts.

I have the Mica Capacitor Value Package and well, im a little confused as to how you differentiate between the 34 capacitors they give you.

For example, one of them would say 2E104K and another might say 250V with 684K underneath.

Could someone please help me interpret these codes into pf values???

PS: more specifically im looking for 0.1, 0.01, and 0.001

[nelson]

we get this question roughly 30 times a month.

use the search function.

try "reading capacitor values"

plus google isalso your friend.  The sites explaining how to do it are ten apenny.

[Kevin_L]

O, well i probably should've mentioned that i have read a number of googled sites and i just dont get it...

None of em seem to have mentioned how to obtain pf values > 1.

For example, if the first 2 digits are the sig figs, and the 3rd is the multiplier. How is it possible to have 0.1 pF...

Please correct me if im wrong, but right now im thinking that if it says 104, than its 1 to 10^-4?

so thats 0.0001 pf? 

But thats not even on the package...

EDIT: What the hell am i saying... that doesnt even make any sense... Now i am truly confused...

[Noplasticrobots]

104 should be 0.1uf, well, at least on ceramics. I'm still a little confused about this myself but it's coming along slowly. After a while you'll start to just recognize the numbers. Same with the resistor color code.

Here's the site I was referred to on cap values:
http://diz.faithweb.com/builders/caps.htm

[Kevin_L]

Ok, i realize this is really noobish, but what is mfd?

[littlegreiger]

I think you're a little confused on the measurement type. On most schematics capacitors are measured in uF values. These are different from pF values whichhave less capacitance than uF. In other words a 1uF capacitor has more capacitance than a 1pF capacitor. When reading capacitor codes it's measured in pF. So 104 would be 100,000 pF or 0.1uF. FYI MFD is the same as uF. Hope this clears things up and if any of this information is wrong please correct me.

[Xlrator]

Print yourself a cheat sheet. After a while it will start to make sense.

I have a chart like this printed out & I keep it with my mica caps when I need to hunt for one.

Here's an html table: http://www.bobknarley.com/synth/capcodes.html

Here's a .pdf printout of the one I have: http://www.em.avnet.com/ctf_shared/pgw/df2df2usa/Ceramic%20Cap%20Codes.pdf

[no one ever]

noobs: http://www.electronics2000.co.uk/calc/calccap.htm

i was confused too, until i found this site.

[D Wagner]

http://www.garrettelec.com/catalog/TECHcatpgs.pdf

About half way down the page is a chart with pF, nF and uF conversions, in an easy to read format.

I keep a copy of this on my cap storage boxes for quick reference.  I have found it to be indispensable.

Derek

[Wild Zebra]

  I got this one http://www.em.avnet.com/ctf_shared/pgw/df2df2usa/Ceramic%20Cap%20Codes.pdf right on the front of my 3 ring binder.
Comes in really handy.  Hope thats a good enough selection to choose from.  Just look up the number on the right and GO. 

[krister]

I use this site to figure out the codes:

http://xtronics.com/kits/ccode.htm

This calculator for resistors:

http://www.breakup.de/resources/resistor.html

Kris

[Nasse]

If anybody wants I can upload my spiffy Jostykit Tropical Fish Capacitor colour code table