madbeanpedals::forum

Projects => General Questions => Topic started by: jeffaroo on November 11, 2012, 07:24:58 AM

Title: cap conversion
Post by: jeffaroo on November 11, 2012, 07:24:58 AM
i have a shopping list and im not sure how to convert the caps. (newbie and all)
22uF
10uF
47nF
3.3nF
100nF
680nF
1nF
47uF
47nF
2.2nF
220pF
220nF
the pF is a no-brainer, but i dont know how to convert the others
the drawing calls for 16v+, smallbear has a lot of 50v. will this be ok ?
i was told to use silver mica caps, but are rated at 500v, is this ok?
i was told to stay away from the greenies
any help would be greatly appreciated   :o
Title: Re: cap conversion
Post by: Pvt. Parts on November 11, 2012, 07:50:19 AM
I doesn't mater if the caps go up on volts its beater to have a nice confort zone of min + 10 volts max 100v (more volts = bigger size)
just add 0 or pass the "." 3 times on the left to pass nF to uF like so 47nF = 00047uF
If you have a 3.3nF pas the . 3 places 3.3nf = 0033uF

and as far as material I go for polyester  at max 100v (the greenies) void ceramic, electo are electro and if you have money go for the box ones or tantalum
Title: Re: cap conversion
Post by: DutchMF on November 11, 2012, 08:18:02 AM
u = micro = 1 x 10-3
n = nano = 1 x 10-6
p = pico = 1 x 10-9

So:
1uF = 1000nF = 1000000pF
Title: Re: cap conversion
Post by: Pvt. Parts on November 11, 2012, 08:57:32 AM
http://www.madbeanpedals.com/forum/index.php?topic=6955.msg59684#msg59684
Title: Re: cap conversion
Post by: Scruffie on November 11, 2012, 12:59:01 PM
Were you given a reason to spend more money on silver mica caps when greenies perform the same function? As long as the rating on the cap exceeds any voltage it will see, it's fine.
Title: Re: cap conversion
Post by: icecycle66 on November 11, 2012, 06:07:33 PM
I have this page open whenever I'm buying caps.

http://www.csgnetwork.com/capcodeinfo.html
Title: Re: cap conversion
Post by: calciferspit on November 11, 2012, 06:21:22 PM
Quote from: icecycle66 on November 11, 2012, 06:07:33 PM
I have this page open whenever I'm buying caps.

http://www.csgnetwork.com/capcodeinfo.html

THIS page exactly. Me too.
Title: Re: cap conversion
Post by: jeffaroo on November 12, 2012, 06:41:51 AM
oh christ ! im even more confused now ! ! !
can anybody decipher the list to a small bear list?
Title: Re: cap conversion
Post by: icecycle66 on November 12, 2012, 07:21:49 AM
Stop worrying about the voltage so much.
So long as the voltage rating is higher than your power source it will be okay.

If you are running pedals on a 9v supply any capacitor over 9 volts is going to work. If you are running high headroom pedals up to 18v, then any capacitor over 18 volts is okay.

Converting capacitors.
Go the the link from earlier.  Ignore the first table.
Go to the table titled "General Capacitance Codebreaker Information"

You can ignore the column labeled "Capacitance Code" for now.
Just look at the cap values you have and look at what they translate into.

for example have a 100n on your list.
The table shows that 100n is equal to 100,000 pF. 
100n is also equal to .1 uF.


Title: Re: cap conversion
Post by: gtr2 on November 12, 2012, 01:05:44 PM
Quote from: jeffaroo on November 12, 2012, 06:41:51 AM
oh christ ! im even more confused now ! ! !
can anybody decipher the list to a small bear list?


Smallbear uses mF for uF.

To the OP

It's easiest if you just make sure all your pedal building caps are rated at 25V and above.  Even if your powering the pedal at 9V some circuits will be doubling the voltage to 18 with a charge pump.
Title: Re: cap conversion
Post by: studiodunn on November 14, 2012, 11:23:42 PM
I never close this page, and have had a MUCH higher first plug success rate since finding it.
http://muzique.com/schem/caps.htm
Title: Re: cap conversion
Post by: msengele on November 16, 2012, 02:17:16 PM
I have been using this site.

http://www.justradios.com/uFnFpF.html

Title: Re: cap conversion
Post by: BraindeadAudio on November 18, 2012, 09:48:50 PM
Go on 300guitars.com he has a great chart you can print out that is great for paying on your bench.
Title: Re: cap conversion
Post by: fuzzymuff on November 29, 2012, 03:31:45 AM
Excuse my ignorance, but can I use a 1uf electrolytic cap for a 1uf film cap?  I was soldering all the caps on a cave dweller build and C10 calls for a 1uf film cap and I ordered a 1uf electrolytic cap instead.  The "1uf" threw me off, as it usually used to distinguish a film cap instead of a film cap.  1000nf would have been clearer to  distinguish for a film cap.
Title: Re: cap conversion
Post by: jeffaroo on November 29, 2012, 04:41:19 AM
i think it will work. if you feel unsure, run to radio shack. they have them