Default units for Capacitors

Discussion in 'The Projects Forum' started by djsfantasi, Mar 5, 2014.

  1. djsfantasi

    Thread Starter AAC Fanatic!

    Apr 11, 2010
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    The attached circuit my son is working on, has several caps without units. I believe they are in mfd, but want to confirm. Note that micro and pico farad values are called out.
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    The unmarked ones will be μf.
    Mfd is much bigger!;)
    Max.
     
  3. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    I think they are in μF.
    The ones that are mentioned with the μF are the electrolitic ones.

    Bertus
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
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    IOW they are are all μF except the 47pf!
    Max.
     
  5. wayneh

    Expert

    Sep 9, 2010
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    It's worth noting that "mfd" occasionally seen on a capacitor label actually means µF. I suppose this is not ambiguous if mF is reserved for millifarads.
     
  6. alfacliff

    Well-Known Member

    Dec 13, 2013
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    but milifarads has never been a standard marking for caps. always microfarads.
     
  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Besides my bench is not big enough! :p
    Max.
     
  8. wayneh

    Expert

    Sep 9, 2010
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    Right, I was just pointing out that "mfd" can be misleading if you don't know the standard.
     
  9. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    A little history from someone who scavanged his first caps from 1940's and 50's TVs:
    mf = mfd = uF
    mmf = mmfd = pF

    ak
     
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