All-righty then. It's really simple, but it took a few years to figure out.
First, I'll go over the list of gear I use for easy setup and tear down. Obviously, get a transmitter. I use the Broadcast Warehouse TX 150. 150 watts. Plenty of power for a small town. Here's the full list of ones they make:
I use the 6th one down from the top- 150W power. They go up to 1000 watts and down to 1watt. UK based company, excellent products.
Next you need an antenna. I prefer one of two antenna's. The first one is an old pirate radio standby called a Comet. Cheap, easy to set up, easy to tune. Model number CFM95SL 5/8 wave.
I mount it using one of these tripods (the base of antenna fits directly into the tripod):
Next, get a cheap laptop.. this is your streaming box. You'll be streaming from a remote location (i.e. your computer at home or work where you're playing DJ), or even a netbook. I like one with a reasonably big hard drive so I can store music on it that the system defaults to if I lose the internet connect (more on that in a bit).
You'll also need a small 2 channel mixer. I like USB mixers because I get the best sound signal out of a cheap laptop from USB vs. the crappy audio outs they put on sub $400 laptops. I use either the Alesis Multimix 4:
Or a Behringer (whatever you can get your hands one).
USB mixers are easier to set up and tear down as well.
You'll need two M/F XLR cables (3 ft.. you're going from the mixer to the transmitter sitting next to it).
And, you'll need some 50ohm coax cable. I would order it from these guys:
Depending how far you're putting your antenna away from your box of goodies.. you'll likely need 50 ft. and more likely 100 ft.
I use one of these yard storage boxes (often used for garden supplies, hoses, etc) to store the transmitter, laptop and mixer:
3 bricks. (seriously).
Last, you'll need a power strip and a 50 or so foot power cord.
So...put the laptop, the transmitter and the mixer into a outdoor storage box (this is the kind you use for garden gear/hoses, etc.). The laptop is hooked to the internet via wi-fi (provided by the 'hosts' home or business) and controlled via logmein or VNC. The laptop also has a local library of music on it in case you lose internet. The antenna goes on an light weight tripod that sites on the roof of a house or business.
15 minute setup: The laptop, mixer and transmitter are already mounted in the box I just put them all in there on the floor of the box. The box has a large piece of tape across the front of it that says "Ham Radio Repeater" (this is for plausible deniability for the 'host' of the setup). You take the box out of your car, you find a good place in the backyard to put it. Usually against the back of the house. You run the power cable to a power outlet (outside or in the garage). You get the laptop hooked up to the local hosts internet via Wi Fi.
Next you take the Coax cable, and you connect it to the transmitter (through the precut hole in the outdoor storage box). You then hook it to the Antenna. You've PRE TUNED (message me if you need the brain dead simple formula for tuning) the antenna for your desired frequency so all you have to do is take the antenna, tripod and cable up to the roof of the house. Find a high point on the roof, and set it upright. Use 3 bricks on each leg lip of the tripods legs to hold it down in high winds.
Go back down, turn it all on. Make sure you're internet connection is working and that Logmein or VNC loaded so you can remotely connect to it. Make sure your transmitter is one and broadcasting.
The way you get content into it is by setting up a shoutcast stream and then just log into that shoutcast stream from the laptop via logmein/VNC. Have local music in the playlist incase you drop the internet connect (it then just moves to the next song in the playlist.. I prefer old Winamp v2.91 for this).
Thats how I set it up in 15 minutes.
Tear down is: Go on roof, disconnect the antenna, take antenna/tripod down throw in the car. Pick up the box, throw it in the car. Actually, it's more like 3 minutes (we actually did this once WHILE the FCC was in front of the house, but that's another long story).
Anyway, I know it seems complex, and it sort of is, but it's sort of not as well.
Here's my blog on running a pirate radio station:
Here's a wikipedia article on the station i started and ran for years:
TL;DR: Put a transmitter, a mixer and a laptop into a box, hook it to a tripod based antenna on a roof, hook it to the internet, turn it on, run away.
EDIT: Per popular request, how to find a frequency and how to tune an antenna (brain dead simple):
You can do it without the SWR meter though. I have, many times, and the formula above works beautifully.
EDIT #1: Here's a link to several of the live shows we did on air:
EDIT #2: Below are pictures of my current setup. It's not set up to be mobile or setup in 15 minutes, but it works for me: