If normalized tables are available these can be easily used without much calculation. A set of these tables is shown in Table 17.2. As can be seen, if the pass-band gain (K) is known it is simply a matter of selecting the appropriate values. Note that several combinations may be possible, as was the case with the previous method.
Remember these are normalized values, and they have to be denormalized as before. This method is a lot easier than the analytical method discussed previously and where tables are available for a certain pass-band gain this method is by far the easiest to apply.
Example 17.5
It is required to design a low-pass Butterworth filter with a pass-band gain of 2 and 3 dB cut-off frequency of 17.2 kHz.
Solution
Consulting the table gives a choice of components in this case, but we will select the following (the choice is purely arbitrary):
These are normalized as usual:
Also, 
. The gain setting resistors are chosen in the usual way.
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