Question A8.17: An amplifier has a power gain of 33 dB. What input power wil...

Now power gain expressed in decibels will be given by:

Thus =  33 10 \log _{10}\left(\frac{11 W }{P_{\text {in }}}\right)

Dividing both sides by 10 gives:

Taking the antilog of both sides gives:

from which:

Note that the antilog or ‘inverse log’ function can be found using your calculator. This sometimes appears as a button marked ‘10x ‘ or is obtained by pressing ‘shift’ (to enable the inverse function) and then ‘log’. In any event, you should refer to your calculator’s instruction book for more information on the keystrokes required!