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>> Now, let's talk about
the two Band-pass Filters.

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See we have two band pass filters right

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here that are coming out
of this power splitter.

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One is at 2.4 gigahertz and
the other is at 2.6 gigahertz,

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and that's because we're using
these for the zero and the

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one of our digital system.

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So at the moment,

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we don't know if our signal is 2.4 or
2.6 gigahertz gets one or the other.

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So we have a filter at the top,

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that's 2.4 and so at
the bottom that passes 2.6.

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If you look really closely,

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you will see that
these lines that are going

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along like this are not actually attached,

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see there's actually a hole between

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these two lines look really closely
and see if I can zoom in on that.

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You are here to see those lines
really are not attached.

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The signal goes through because
it's high frequency and it

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actually couples across
these capacitive gaps,

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each of these gaps are capacitive.

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When we model these filters
or when we design them,

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they are a series of
inductors and capacitors.

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This is actually a picture of
how those circuits are designed.

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They are capacitor, inductor,
capacitor, inductor and so on.

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You'll learn to design
these circuits when you take

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a good signal processing class and to

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build them in this particular form
in microwave engineering.

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But they are just a series of inductors and

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capacitors that make up a band-pass filter.