A Word on Legality Issues
Depending on where you are in the world, there are a few different things that make pirate broadcasts illegal. The cardinal sin stateside (as far as the FCC is concerned) is broadcasting on unlicensed radio spectrum. Although the FCC is often a buzzkill, in many ways its rules regarding pirate broadcasts make sense. If a high powered transmitter lands in the hands of a reckless amateur, all sorts of havoc can be wreaked on local radio communication. This can not only cause problems in the public safety sector (fire, police, emergency services), but it's also likely to disrupt the transmissions of legit broadcasters who actually paid for their chunk of licensed spectrum.
Also, there's the issue of royalties. Setting up your own "All 'Aqualung,' All the Time" station might sound great, but if your transmission is located it's likely that the record industry will want a piece of the action. Depending on how flagrant the offense, pirate broadcasters can be hit with a combination of back royalties and fines -- and that's on top of financial beating the FCC dishes out. Naturally, we wouldn't condone illegal conduct of this type, but we imagine that this information might be useful for hobbyists.
Yes. Hobbyists.
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Step 2: Assemble Your Studio
With a general format in tow, you should be ready to start collecting equipment. The technically inclined can go the distance with a DIY kit, but rookies are probably better off hitting up amateur publications and websites to find the right gear. Although there's lots of room for customization, the outcome is basically the same -- you're looking to chain together components that filter, convert, and broadcast your audio signal. Your gear will breakdown into three categories:
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Step 5: Keep the Authorities Guessing
For a lot of radio pirates, gaining exposure through loyal listeners is the big draw for setting up a station. But keep in mind that the more exposed you are, the more likely you are to garner unwanted attention. Long and symmetrically scheduled broadcasts on the same frequencies can be a recipe for trouble, so make sure to mix things up. Never give out any personal information, location data, or landmarks over the air. If you were savvy enough to build a mobile rig, even better. After all, it's harder to catch a moving target.
More:
http://howto.wired.com/wiki/Set_Up_a_Pirate_Radio_Station