First, a disclaimer: it is a scam. You will not get anything that approaches something that resembles projection TV.

The plans attempt to turn your television into a magic lantern, which is itself an application of camera obscura.

|  _ .
| / \     .             _________________________ 
| \ /                  |          ^l umop apisdn |
|  |             .     |           . _=____=__   |
| /|\                 /\      .     |  _____  |  |
|/ | \               (  ).          | |  W  | |  |
|  |                  \/      .     | |__o__| |  |
| / \            .     |           .|_________|  |
|/   \    .            |_________________________|
|     .
The detailed instructions (available on the net for free! save your $$$) make you build a dark box around your television (turned upside down!) using cardboard and an opening where a fresnel lens(sold by the scammer at a heavy markup, of course) is fitted. Once built, the setup is adjusted to project the image on a wall.

Now here are the caveats to this (and why it's a scam):

  • This scheme requires the TV brightness turned up all the way. This means a very blurry bloomed image and will dramatically shorten the life of the phosphorus and CRT guns.
  • The TV needs to be standing upside down, something it was not designed to do, and results in screwed up linearity (distorted colors).
  • Encasing your TV in a box, upside down will adversly affect ventilation making it overheat. (thanks spiregrain)
  • Even with the brightness all the way up, the image is very dim, requiring the room to be perfectly dark, daytime viewing is out.
  • The fresnel lens used to focus the image is not at all optically perfect (whadya expect for $10) and will severly distort the image.
  • The TV tube is curved, so the image will not be projected from the focal point at the edges.
In summary, you get a poorly lit, distorted and blurry "projection TV" which you can only watch during a moonless night.

Well it's not all bad. It could be used semi-effectively for a couple of applications:

  • Projecting Winamp or Cthugha visualisations on the ceiling during a party
  • Projecting scary pictures on your front window as part of a Halloween night decorations
  • (/msg your idea here)
    Drinkypoo: you don't have to turn the TV upside down, you can swap wires on the yoke. (The yoke's on you if you break your TV doing that.)