i need a bandpass filter of 38khz

Discussion in 'General Electronics Chat' started by leonheard, Jan 22, 2013.

  1. leonheard

    Thread Starter Member

    Jan 8, 2013

    i need a bandpass filter of 38khz, i want to do it with analog components, i mean no chip, only analog. thanks :)
  2. tshuck

    Well-Known Member

    Oct 18, 2012
  3. Papabravo


    Feb 24, 2006
    We're going to need a little bit more. So I gather that 38 kHz is the "center" of the passband. Where are the upper and lower stop bands, and where are the upper and lower transition bands? What requirements do you have for ripple in the passband and the stop bands?

    The basic procedure is to pick a topology, Chebyshev for example, and design a low pass filter with a corner frequency of 1 radian/second. Then transform the low pass topology into a band pass topology, and finally scale up to the desired 38 kHz frequency. There are any number of online calculators that will do this for you.

    Then you have to find the components. Capacitors should be NPO or COG and the inductors you will have to find core material and wind yourself.

    Good Luck
    leonheard likes this.