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Additional remarks

Sonic additional remarks on thc procedurę now follow.

•    The stubs and the main linę can be of different characteristic impcdances. We should then use three different charts. and work in normalized admittances on cach.

But to transfer values from one chart to another, e.g. transferring bs2 and bsi to get si and s2, we must flrst un-normalize using the characteristic admittance of the main linę, and then re-normalize using the characteristic admittance of the stub linę.

•    Not all valucs of admittance can be matchcd by thc above tuner. As an example. we cxaminc the forbidden region for load admittances on thc Smith Chart. We find thc rcsult is the interior of the g = 2 circlc.

•    In such cases. we can insert a section of transmission linę bctwccn the load and thc tuner, and in so doing transform the load admittance to a value which is well outsidc the forbidden region.