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  1. #1
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    making a electret mic pre amp using la 3161 ic

    Hello sir,
    i ve an ic LA 3161 , now im trying to make a pre amplifier using this one for a samll electret or condenser mic , is it possible or not please tell , or if possible then have me a proper circuit diagram , im unable to proceed a single step here for now in my practice please help
    thanks

    •   Alt7th July 2012, 00:18

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    Re: making a electret mic pre amp using la 3161 ic

    You could try it out, and let us know. The datasheet has a circuit diagram.
    I highly doubt many (any?) people have attempted with such an ancient chip, so you'll be treading new ground.
    Most people who want a mic preamp would go for something more modern. If you want to use simple components then
    the website referred to you in one of your other posts has many transistor circuits, including mic amps, just search for the word electret.



    •   Alt7th July 2012, 01:56

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  3. #3
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    Re: making a electret mic pre amp using la 3161 ic

    kk sir i ll go with that too ,
    let you know about what i did just half an hour before :)
    have a look here
    simple preamplifier with one transistor.jpg
    i replaced it with the same value but with a higher voltage limit condencer so now im getting some less distortion now . bur not with totally erased off

    - - - Updated - - -

    is there any danger of adding a telephone mouth piece here in place of this mic :) please tell



    •   Alt7th July 2012, 02:43

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    Re: making a electret mic pre amp using la 3161 ic

    The biasing arrangement permits high voltage gain. However it has a high output impedance.

    As it is, it will not drive a speaker, not even headphones. The waveform will be distorted if you load the output too much.

    It will be handy to have a volume control.

    Try 1uF for C1. It should let through more of the lower frequencies.

    The 100k resistor R2 could be reduced. Try 10k. Or substitute a 100k potentiometer. Dial it around and see if you can find a spot where you hear the least distortion. This is vital, because you are trying to find a proper voltage swing for the transistor.

    The waveform should hover in a middle region between the supply rails.



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    Re: making a electret mic pre amp using la 3161 ic

    Hello sir
    Im facing some problems relating new posts here im unable to post a new thread here , i hardly posted two of them cause for every next page i automatically logged out from the forum
    please help . . thankssssssssssss

    - - - Updated - - -

    Hello sir
    Im facing some problems relating new posts here im unable to post a new thread here , i hardly posted two of them cause for every next page i automatically logged out from the forum
    please help . . thankssssssssssss



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