any noise through capacitor

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  • pankaj
    New Member
    • Aug 2010
    • 1

    #1

    any noise through capacitor

    hello frens,

    i designed a small circuit for measuring capacitor but there is some value( ~ 280 pf) its behavior is unpredictable. in circuit only resistance and capacitor is connected so no way to occurrence of any resonance condition....



    variable capacitor connected in series with 470nf capacitor.

    please help to find out the solution...........
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30991
    • Albion

    #2
    Re: any noise through capacitor

    could be parasitic resonance, are the tracks short & straight?
    try putting ferrite rings on the cap legs.

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