The treatise, while scholarly, is, I think, too verbose. The timber is obscured by the arborescence. (Look it up.)
Be that as it may, there is a serious omission.
It concerns expressing amplifier gain in dB.
This should be done when, and only when, the input and output impedances are equal.
Consider an amplifier about which we are told only that its voltage gain is 10.
Not only neophytes, but many experienced practitioners of the electronic art, will jump in with both feet and declare that the gain is also 10dB.
Now let's reveal the amplifier's input and output impedances to be 1000 and 600 ohms respectively.
Power in the input impedance is 1mW. That in its output impedance is 166.7mW. That's a gain of 22dB.
Change the output impedance to 50 ohms. Output power 2W. Gain 33dB.
Now you see the fallacy of ignoring or overlooking the impedances.
An example in the text seems to indicate confusion on its author's part.
Example: The voltage into a 600 Ω audio line amplifier is 10 mV, the voltage across a 600 Ω load is 1 V. Find the power gain in dB.
The word "power" is irrelevant. Given that both input and output impedances are equal, as they must be in order not to invalidate the use of dB notation, it matters not whether voltages or powers are being considered. The result is the same.
Be that as it may, there is a serious omission.
It concerns expressing amplifier gain in dB.
This should be done when, and only when, the input and output impedances are equal.
Consider an amplifier about which we are told only that its voltage gain is 10.
Not only neophytes, but many experienced practitioners of the electronic art, will jump in with both feet and declare that the gain is also 10dB.
Now let's reveal the amplifier's input and output impedances to be 1000 and 600 ohms respectively.
Power in the input impedance is 1mW. That in its output impedance is 166.7mW. That's a gain of 22dB.
Change the output impedance to 50 ohms. Output power 2W. Gain 33dB.
Now you see the fallacy of ignoring or overlooking the impedances.
An example in the text seems to indicate confusion on its author's part.
Example: The voltage into a 600 Ω audio line amplifier is 10 mV, the voltage across a 600 Ω load is 1 V. Find the power gain in dB.
The word "power" is irrelevant. Given that both input and output impedances are equal, as they must be in order not to invalidate the use of dB notation, it matters not whether voltages or powers are being considered. The result is the same.