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enter image description here Here I'm trying to find the overall voltage gain. I did everything correctly, except out of nowhere, the gain in dB was 54dB, not 50dB. I don't know why. Here's the solution: enter image description here

And here's the figure (or problem statement)

enter image description here

Can someone explain why?

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    \$\begingroup\$ Just looks like a typo. The professors who write textbooks and the grad students who proofread the problem sets at 3 AM are not infallible. \$\endgroup\$ – The Photon Sep 20 '16 at 17:33
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could be a typo... quick analysis....

  • Voltage gain, Av remains ~50dB or 49.7 @16Ω assumes Av=no load
    • (negligible load loss -0.3dB @16Ω)
  • Current gain, Ai=Av*Rin/Rout or in log format Av(dB)+Ar(dB)
    • where Rin/Rout= 1M/{1kΩ:16Ω} = {1000:62,500} = {60dB:96dB}
  • Power gain, Ap(dB)=Ai(dB) + Av(dB) = {50+60;49.7+96} for {1kΩ:16Ω}
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