Böcker av J Richard Hollos

We write books, so we spend a lot of time indoors. When we go outside the air seems so much fresher than inside. Is there any way to recreate that fresh air feeling indoors? That's a question we've been trying to answer for a few years now. We think we've found an answer. It's called photocatalytic air purification. What exactly this means is described in the first section. The final section of this guide describes in detail how to actually make an air purifier that uses photocatalysis to remove volatile organic chemicals (VOCs) from the air.The photocatalytic air purifier which we've created and describe here has made a positive difference to us. We set it on a table next to where we work and run it whenever we're working. When it's running, the air seems fresh, similar to having a nearby open window. It's not magic but it has reduced the incidence of itchy watery eyes, irritated throat, runny nose and general feeling of malaise that VOCs can produce.

This book should allow anyone with basic electronics skills to quickly design a passive Butterworth filter. All possible low pass and high pass filters up to tenth order, and all possible band pass and band stop filters up to eighth order are covered. Schematics and component values for these filters are given along with formulas for scaling the values to the particular frequency the filter must operate at. There is a design example for each of the filter types that shows how to scale the component values. A Spice simulation file for the design is given along with the frequency response. If you want band pass or band stop filters higher than eighth order the book explains how to use a low pass filter to construct them. So the information is there to construct filters up to twentieth order but we don't recommend trying to do that. The non ideal nature of the components makes it hard to get the expected extra performance. The website for this book is http: //www.abrazol.com/books/filter2/ where we will post related resources.

Creating Melodies is a companion to our book Creating Rhythms. The book will show you how to explore the infinite space of melodies.Like the rhythms book, it comes with software that you can download from the book's website. With the software you can generate countless new melodies and variations on old ones. Combine those melodies with rhythms from our rhythms book and you have an endless source of inspiration for new music.You can listen to the many example melodies in this book as MIDI and MP3 files on the book's website at http://www.abrazol.com/books/melody1/We had a lot of fun writing this book. In fact it took us so long to write it because it was hard to tear ourselves away from creating so much interesting new music and write up the results. Now you can have fun with it too!