Current Adapter

Discussion in 'General Electronics Chat' started by Dr.killjoy, Feb 4, 2014.

  1. Dr.killjoy

    Thread Starter Well-Known Member

    Apr 28, 2013
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    I know Dave Jones has built these but I want to know if someone here has played around with one of these or built there own????
    Also have anyone ever built one with through hole components ??









    Thanks
    Jason SR
     
  2. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    I've seen most of Dave's videos about the uCurrent but never seen one in person. The uCurrent Gold he just came out with seems top-notch, though I generally don't have a need to measure microamps.
     
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  3. Dr.killjoy

    Thread Starter Well-Known Member

    Apr 28, 2013
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    Why would you need to measure that small of a current? ?
    I see people building them but how much use will they really have? ?






    Thanks
    Jason SR
     
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  4. nsaspook

    AAC Fanatic!

    Aug 27, 2009
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    ErnieM and Dr.killjoy like this.
  5. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    I have one; don't use it much. Indispensable when you need it.
     
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  6. #12

    Expert

    Nov 30, 2010
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    If you have a Fluke, you already have a microamp meter.
     
  7. ScottWang

    Moderator

    Aug 23, 2012
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    I've tried to do that and already prepared the parts, but the parts are too small, it's not easy to solder them, my friend said that he wanting to prepare the SMD PCB, but there is no message any more, so the parts still sleeping in the case.
     
  8. Dr.killjoy

    Thread Starter Well-Known Member

    Apr 28, 2013
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    I am running A fluke 87 Series I DMM.. Will hurt the meter or screw anything up? ??
    I will be building one myself when I get caught up..

    Thanks and I was thinking about getting one .. I also trying to see if anyone built here anything better or had another way of doing things???
     
  9. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    A fluke 87 can read to 0.01 uA with no tricks - although I like #12's mV trick on a 10M ohm input resistance.
     
  10. inwo

    Well-Known Member

    Nov 7, 2013
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    Can that be concidered a μA meter with 10M resistance?:confused:
     
  11. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    The 87 V on uA setting or NT's trick using mV setting?
     
  12. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    I doubt it'll be accurate at all in that range, that's right down in the noise. Do you mean it has a 0.01uA resolution? That's another matter--still in the noise, but is not the main measurement.
     
  13. inwo

    Well-Known Member

    Nov 7, 2013
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    #12s trick.

    Wouldn't you be measuring current across a 10Mohm shunt.

    The reading would be correct. But the circuit would be affected significantly.

    No?
     
  14. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    You are right, I meant to imply that uAmps are easily measured with many modern handheld meters.
     
  15. #12

    Expert

    Nov 30, 2010
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    I would never trust a flicker in the least significant digit, but I have used that "trick" and found the results to seem perfectly accurate. Look at this old Vbe/Ic graph I did with this method and ask yourself, "How could it match the theoretical results so well if the measuring premise was invalid?"

    (and I think I got the labels written in wrong.)

    as for "significantly" affecting he circuit? I was careful to remind you that the voltage burden of the meter is 10 millivolts at 1 ua.
     
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