Chapter 9, Create Time-Shifted FM Radio
Whole-House Audio
In this phase, youll create a system for distributing audio from your com-
puter throughout your house. If youre lucky enough to already have such
a system in place, or if you only plan to listen to the time-shifted radio
through a single pair of speakers, you can skip this phase.
Sound quality, cost, ease of installation, and portability are the most sig-
nificant factors when choosing a whole-house audio system. At the high
end, you can install whole-house audio that provides home theaterquality
sound to multiple speakers in every room of your house. These systems
typically provide controls built into the wall of each room that allow you
to control the volume and other aspects of the audio equipment. You can
find an excellent description of such systems at http://www.hometech.com/
Quality is not the most important factor to me, though. Cost is important,
because honestly now, there are much more important things to spend
money on than whole-house audio. Plus, I dread the idea of running wires
all around my 1950s house, and it would take me so long that I’d probably
never complete the project anyway. Portability is important, too. If I move,
I wouldnt want to leave a wired whole-house system behind. Chances are
good that it wouldn’t improve the value of my house much, so I’d be taking
a loss.
For this project, I found a whole-house audio solution with acceptable qual-
ity that was less than $100, installed in about an hour, and that I can easily
take with me anywhere I move. This system uses a wireless protocol, similar
to 802.11x, but significantly easier to install (although less secure). And as
if that weren’t perfect enough, it turns out that I already had compatible
wireless clients spread around my house. Basically, I’m going to install a
pirate radio station.
You dont need to be a rebellious DJ-with-a-cause to
set up your own pirate radio station. In fact, you dont
even need to be a pirate, or to break any laws. You can
legally set up an FM radio transmitter that can broad-
cast a short distance, as illustrated in Figure 9-7. I’ve
done this in the past to connect my MP3 player to my
car stereo. For about $30, I bought a radio transmitter
from the neighborhood electronics store. That transmit-
ter worked only for a few feet, though, so it’s not good
enough to broadcast around an entire home.
This project will provide some background information
about FM transmitters and the laws that regulate broad-
casting in public frequencies. I’ll walk you through the
process of choosing from the many FM transmitters
Figure 9-7. Want your MP3s in a different
room? Build a tiny radio station!
Whole-House Audio
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11/24/2004 1:55:49 PM

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