FIL I.1

In the previous post we went over passive LC filter design.  LC filters do have many advantages: they are simple to understand and design and they don’t require an external power supply.  They also are the only solution for higher frequencies.  That said, they cannot provide gain.  Instead, some power is lost when the signal goes…

The math behind filter design is actually very complex, and the equations that determine component values are complicated.  Fortunately, most of that complexity will be transparent to you!  Good news, you’ll never have to work from scratch when designing filters.  Instead, filter design relies on using tables of normalized values, then extrapolating these values…

For a given cut-off frequency and filter order, there are multiple solutions for component values.  Depending on these values, different responses can be created.  Two filters with the same component arrangement, the same cut-off frequency, and the same order, can have different component values and different Bode plots.  The most common filter families are the…

Filters are an important building block you will find in nearly all fields of electronics.  They are of particular interest to the ham radio experimenter and RF designer.  Out of all the building blocks of radio electronics, filters are perhaps the most simple to understand.  Simple doesn’t mean unimportant however, as filters are a necessary…