javatelevision

How to write a Java program to send signal from a PC to a TV via coaxial cable?

I have a PC with a TV card, it connects to an antenna via a coaxial cable, so at the back of PC there is a coaxial cable connector, the PC is in the basement. 60 feet apart in the living room above there is a big screen TV, the only way I can think of to possibly transfer a signal from the PC to the TV is an existing coaxial cable which extends from the basement all the way to the TV, so I wonder if there is a way to write a Java program to send TV signal streams to the TV via the coaxial cable ? A few points need to be mentioned here :

  1. I've thought of HDMI, but no HDMI line can be 60 feet long.
  2. Can't move the PC closer to the TV.
  3. Don't want to buy extra hardware to transmit signal from PC to TV
  4. I know the coaxial cable connector at the back of the PC is for taking in antenna signal not for output use. What I'm attempting is to use it to output signal.

Is it doable ? If so where can I find some sample Java code ?

Edit : This is just a technical challenge to see how far I can go with Java on the software side, sort of flexing the intellectual muscle, so to speak. Trying to send Internet video stream info from PC to a TV via a coaxial cable between them.

Solution

  • As other people have said, there's no way to do this with the TV in card, as that's built for taking an NTSC (Or ATSC/QAM if it's newer) signal and converting it into a MPEG stream.

    I know that an NTSC composite black and white signal (I imagine PAL too, I think the two are similar for luma) with a micocontroller, a few pins, some resistors, and judicious use of cycle counting.

    If you can get low level (e.g. bit-banging) control of a parallel port from Java, you might be able to do something similar, if you get the timing tight enough.

    However, I see several possible issues:

    1. I don't know if the parallel port can bit-bang fast enough to do this (I know an 8051 running somewhere around 12MHz can barely pull this off)
    2. Any modern multitasking operating system will probably context-switch away to another thread while trying to do this, and throwing off timings.
    3. On top of context switches, I know the garbage collector in .Net (I'm not a java dev, so I'm not sure on the java side of things here), will pause active threads to collect (At least in versions previous to 4, i think that changed in 4), this will, again, affect timing.
    4. I don't know if parallel signals will travel 60ft.
    5. If somehow all of the above prove possible, you have a low resolution, monochrome display (4 digital lines would net you 16 shades of gray on the other end, with the appropriate resistors)