R in an RLC bandstop filter

Discussion in 'General Electronics Chat' started by Zuma, Mar 13, 2011.

  1. Zuma

    Thread Starter New Member

    Mar 12, 2011
    I'm trying to understand the impact of the 500ohm resistor in this simple RLC stopband filter circuit:

    http://www.falstad.com/circuit/#$+1...6+256+96+0 o+8+64+0+34+1.25+1.953125E-4+0+-1

    (1kohm resistor is the load)

    I understand that the LC components resonate at a frequency of:

    F = 1/(2*PI*sqrt(L*C))

    But where does the resistor value fit into that equation, if I want to use it to calculate an L or C to best block a given frequency?

    I'm interested in this from the math side, so ideal components are fine.
  2. wayneh


    Sep 9, 2010
    The resistor just limits current and damps the resonance. I guess you knew that, but anyway the R doesn't affect the frequency of resonance, only the amplitude of it.

    You might consider posting this in the electronics chat area instead of here in the Projects forum.