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    What is the input capacitance of JFET at 150 Mhz?

    I have some few doubts and I want you to clear those.

    I want to know the input parasitic capacitance of JFET at 150 Mhz ( the jfet I am using is J460).

    Also I want to know the resistances for biasing the jfet in CS configuration.

    One more doubt. I want to calculate the parasitic inductance of a wire at 150 Mhz.

    Thanks in advance.
    Mind is like a room. You have to keep only useful things in that room.

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    Re: What is the input capacitance of JFET at 150 Mhz?

    google it
    ALL Transistors Datasheet
    if u dont know the inductance apply a sine wave to coil thru different resistors and check voltage and current on resistor then u can calulate having z the induction
    there is plenty of info on google
    good luck

    liked your ...human brain.. sheerlock.. so ill let u do some work your self before handing it all to u.



    •   Alt3rd February 2012, 14:09

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    Re: What is the input capacitance of JFET at 150 Mhz?

    I saw the datasheet. It's at some other frequency. I want to know the capacitance at this frequency.
    Mind is like a room. You have to keep only useful things in that room.



    •   Alt3rd February 2012, 14:19

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    Re: What is the input capacitance of JFET at 150 Mhz?

    Dear iVenky
    Hi
    The input capacitance of a transistor , will not change with frequency , it's xc will change by changing the frequency . it's capacitor , with changing at amplitude will change ( one of effects of miller ).
    Respect
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    When you sensed that i can help you , feel free to ask me .
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    •   Alt3rd February 2012, 14:36

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    Re: What is the input capacitance of JFET at 150 Mhz?

    Quote Originally Posted by goldsmith View Post
    Dear iVenky
    Hi
    The input capacitance of a transistor , will not change with frequency , it's xc will change by changing the frequency . it's capacitor , with changing at amplitude will change ( one of effects of miller ).
    Respect
    Goldsmith
    Okay do you have any idea about my other questions?

    ---------- Post added at 19:26 ---------- Previous post was at 19:09 ----------

    Please tell me the biasing resistor values of the JFET in CS mode.

    It's urgent.
    Mind is like a room. You have to keep only useful things in that room.



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    Re: What is the input capacitance of JFET at 150 Mhz?

    Its not so easy u need to know the specs and calculate
    here is a detail link with all the munbers
    Transistor Fundamentals: JFET Amplifiers

    better link
    Junction Field Effect Transistor or JFET Tutorial

    biasing jfets
    Last edited by dselec; 3rd February 2012 at 15:26.



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    Re: What is the input capacitance of JFET at 150 Mhz?

    Dear iVenky
    As dselec said it is not easy at that frequency . and is i know , the frequency response of a CS amplifier is not good . so try CG and CD arrangements . by the way , why you want design a class A amp for your aim ? as i know , at this frequency , the class C or the other class , are more useful .
    Best Wishes
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    Re: What is the input capacitance of JFET at 150 Mhz?

    Okay. It's CG. Now tell me the biasing resistance values.

    Thanks in advance.
    Mind is like a room. You have to keep only useful things in that room.



    •   Alt3rd February 2012, 15:33

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    Re: What is the input capacitance of JFET at 150 Mhz?

    Didnt u see my link ?
    it says r1 and r2 must be on your choice according to what current u need and vgs of your transistor.


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