Logarithmic Amplifier

Discussion in 'General Electronics Chat' started by ELECTRONERD, Jul 17, 2009.

  1. ELECTRONERD

    Thread Starter Senior Member

    May 26, 2009
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    Hello,

    I have come across Logarithmic amplifiers and wanted to know what they are typically used for and why?

    I'd appreciate it!

    Thanks!
     
  2. millwood

    Guest

    they can be used in analog computers (multipliers, dividers, and log/exponential functions), or level compressors (for speech or music for example), to name a few.
     
  3. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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  4. Wendy

    Moderator

    Mar 24, 2008
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  5. someonesdad

    Senior Member

    Jul 7, 2009
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    In the 70's, HP made a bench instrument that was a logarithmic amplifier. I remember using one briefly in the early 80's. They were handy because they measured a voltage with about 2 significant digits over a wide range and there was no need to change range switches. As I recall, they also had a DC output proportional to the log of the signal amplitude.
     
  6. Wendy

    Moderator

    Mar 24, 2008
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    Electronic slide rule, anyone? <sigh> I doubt anyone under 40 remembers what one is.

    Sometime I feel old, sometimes I'm told I'm old. Being an advisor for a boy's youth group (DeMolay) will do that.

    They try to do it nicely though.
     
  7. ELECTRONERD

    Thread Starter Senior Member

    May 26, 2009
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    Oh ok, thanks for all the help guys! I take it that their fairly similar to op amps and in amps? Thanks!
     
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