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Homework Help: RF Amplifier Design!

  1. Jun 4, 2013 #1
    Hey....I was trying to design a practical of mine.....There is this question where I am supposed to design a tuned RF Amplifier with gain 100 for a frequency 720KHz with BJT. I know that I will get frequency with LC tank circuit but the gain is a different story. I have searched 5-6 books and am yet to find a correct design procedure for such an RF amplifier.

    How's is this designing done??....Or atleast can someone point me towards the place where I can find the design??

  2. jcsd
  3. Jun 4, 2013 #2


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    Staff: Mentor

    Are you supposed to get that gain with just one BJT, or can you cascade two stages?

    Wikipedia has some pretty good introductory pages on transistor amplifiers. See the "Radio" section of this page for example:


  4. Jun 7, 2013 #3
    It has to be single staged amplifier.....
  5. Jun 7, 2013 #4


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    Staff: Mentor

    That's not going to be easy, depending on the signal amplitude that you have to work with. Do some reading about common-emitter amplifiers, especially how to get high gain out of them.
  6. Jun 11, 2013 #5

    rude man

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    Homework Helper
    Gold Member

    I think it's barely doable, not a good design but it might work in the lab. Consider L = 1 mHy for the coil. Might be a pretty large-volume coil to get a Q of at least 20. Run the transistor around 9 mA.
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