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    how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    with the following components, RB1 15K, RB2 =2.2K, RC =10K, RE =830 ohms.
    AC signal is 10Mv, 1KHz, Vcc 12, for BJT Common Emitter amplifier

    the present Av gain is 12
    how can i reduce it to 10 ?

    •   Alt12th January 2018, 16:01

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    Re: how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    Badly worded question:
    hfe is not indicated above, and you mentioned Mega volts where it would probably be mili volt.
    In addition, is there no reactive component in the circuit (eg. capacitor) ?
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    •   Alt12th January 2018, 16:16

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    Re: how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    Quote Originally Posted by nyameephraim View Post
    with the following components, RB1 15K, RB2 =2.2K, RC =10K, RE =830 ohms.
    AC signal is 10Mv, 1KHz, Vcc 12, for BJT Common Emitter amplifier

    the present Av gain is 12
    how can i reduce it to 10 ?
    the transistor hfe is 300



    •   Alt12th January 2018, 16:28

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    Re: how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    Ok, did you even tried by yourself with the information sources available over there ?

    https://en.wikipedia.org/wiki/Common_emitter

    You will have to parameterize some values (since the gain is defined), and in the end it will not be a direct numerical calculation, but the resolution of an algebraic equation, a nice opportunity to learn.
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    Re: how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    Quote Originally Posted by nyameephraim View Post
    RC =10K, RE =830

    the present Av gain is 12
    how can i reduce it to 10 ?
    Av ≈ RC/RE


    1 members found this post helpful.

    •   Alt12th January 2018, 19:37

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  6. #6
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    Re: how can i increase Av gain of BJT from 10 to 12 with AC signal of 10Mv and 1KHz

    On another website forum he posted a schematic larger than my neighbourhood so I fixed it and made it look normal.
    I answered his question by posting a simulation.
    He said he tried it and it did not work.
    EDIT: I notice that on this website the title says he wants to increase the gain but his paragraph says he wants to decrease the gain.



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