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    pre emphasis circuit

    what is Pre-emphasis and DE-emphasis circuits in FM voice radio?

    what is do?

    Please send information.

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    •   Alt25th September 2007, 19:15

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    pre-emphasis

    Pre-emphasis shapes a signal before it is sent and post-emphasis shapes it after it is received. The idea is to compensate for distortions that the transmission channel may/will introduce.

    Radars also sometimes use this to spread a pulse and thus transmit more power. Then on reception compress the pulse to improve range resolution.



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    site:edaboard.com pre-emphasis

    please give me some OPAMP circuit for pre-emphasis and de-emphasis.



    •   Alt26th September 2007, 18:42

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    pre emphasis and de emphasis

    Deemphasis circuit is trivial. Use current generator which supply parallel RC whose time constant is 50us or 75us regarding what you need.



    •   Alt26th September 2007, 19:47

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    Re: Pre-emphasis and DE-emphasis circuits?

    any idea on matlab source code of this pre-emphasis FIR filter?

    I have 1 coding in my hand but the number of order is too high!!! i doesnt want the number of order higher than 32.

    Any idea?



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    Re: pre emphasis and de emphasis

    [I need pre emphasis and de emphasis circuits using opamp



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    Re: pre emphasis and de emphasis

    Quote Originally Posted by zingade_se View Post
    [I need pre emphasis and de emphasis circuits using opamp
    dear you all

    in PCIe gen 3, why do we need preshoot technique ?

    thank you in advance



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    Re: Pre-emphasis and DE-emphasis circuits?

    Since noise is constant per unit bandwidth , noise is thus greater with higher center frequency
    i.e. bass 50 ~500Hz is lower bandwidth than 500~15kHz so the treble is amplified on transmitter and reduced in receiver so response net is flat.

    I recall there is 15dB of pre-emphasis but I forget the breakpoint frequency.
    The best question deserves a better answer.
    Be kind to others helpedme & [solved]
    Ohm's Law of life... Tony Stewart EE since 1975



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    Re: Pre-emphasis and DE-emphasis circuits?

    dear sunny ?
    could you explain more about preshoot in detail ?
    thanks



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    Re: Pre-emphasis and DE-emphasis circuits?

    visualize treble control set to 15dB gain for Transmitter (Tx) and Receiver treble set to -15 dB before the equalizer.

    This is pre-emphasis..(Tx) and de-emphasis (Rx)

    not preshoot.
    The best question deserves a better answer.
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    Re: Pre-emphasis and DE-emphasis circuits?

    i think there is a different view of PRESHOOT.
    this is its definition :
    " Preshoot is a new feature designed to improve the signal in the following bit time by boosting the voltage in the current bit time"

    why it can improve signal ?

    pls



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