We created one that went live the minute analog tv went dead. We're still the only analog station in NYC, but please join us in making more!! Long live analog tv.
Step 1: Find a Free Channel.
The best option for finding free space is the FCC's own search engine for these things:
Simply type in the channel (try a range of 14 to 35) and your state, along with the type of broadcasts available. Try to avoid channels that correspond to channels in your area (i.e. CBS 2 in New York). While they might be free because of the DTV transition and broadcasting in a higher channel range, they are still virtually broadcasting through that channel and might also have dibs on it for visual identity's sake.
Step 2: Find a TV Transmitter.
1. buying multiple short-range consumer transmitters
2. commissioning a transmitter from Free Radio Berkeley Http://freeradio.org
3. building your own
The first is relatively cheap-yet-clumsy, the second relatively expensive-yet-simple and the third a bit less expensive but a (rewarding) challenge, but all three result in a rather robust analog broadcast.
Step 3: Step 2, Method 1: Multiple Short-range Transmitters
Most of these transmitters require an RCA composite or Coaxial input, so any video source would work. To get composite video from a computer one simply needs to buy some kind of VGA/DVI to Composite converter or a PC TV converter, which usually range from 35 to 200 dollars, depending on the quality.
The channels that these transmitters broadcast on are also adjustable; see the transmitter's instruction manual for details on that.
Networking the transmitters can be achieved by daisy-chaining the antennae with the Coaxial In/Out ports on each transmitter using long, 500-foot cables.
Step 4: Step 2, Method 2: a Commissioned Free Radio Berkeley Transmitter
Like with the previous ad-hoc broadcast method, any analog video source will work. However, if you plan on using composite video you will probably need some RCA-to-coaxial converters for the video and audio, which are really just a few bucks at radio shack.
Stephan Dunifer, the founder of Free Radio Berkeley, has been building these transmitters for the past thirty years and is very helpful if you have any questions.
Step 5: Step 2, Method 3: Building Your Own Transmitter
In 2008 the media collective !Mediangruppe Bitnik created a freely-downloadable pocket zine that contains detailed instructions for creating your own short-range television transmitter:
This transmitter also accepts any analog video source you can throw at it.
Step 6: Install Transmitter
Long runs of cable between your antenna and the transmitter will degrade your broadcast range, so the shorter the distance the better. We decided to put our transmitter up on the roof and run the A/V cable up from our broadcast room.
In order to protect our transmitter from weather and rain, we bought a huge tupperware container and retrofitted it with holes for ventilation and cable runs to house and protect the delicate electrical components.
Step 7: Step 3: Content!
If you're using a computer as a video source, your possibilities are potentially more infinite. However, if you still feel scraped for content there are various webscraping tools at your disposal, including Yahoo Pipes, Google Mashup Editor or Youtube's own API. Enclosed is a flow chart that explains our approach.
We create our own custom web scrapper at http://OMGimon.TV. We're happy to share our code if you're interested in building something similar or building a webscraper.