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OK, say you have people talking. You point a TV camera at them. Reflected light and sound waves go into the camera. The camera sends that info through wires (electrons?) to a transmitter, which converts that info into radio waves and sends out the radio wave to a TV antenna which catches the waves, changes them back to electrons through wires into your TV set which then turns the electrons into a picture on the screen and sound through the speakers? How do these electrons know how to make a picture? How do they know how to make the sounds that make the words you hear? It seems almost too complicated to even think about much less invent. Just take it a step at a time. How does it work that you point a TV camera at something, and then make it show up as a picture, even in the same room? Then how do you make that same picture (and sound) show up in a room thousands of miles away? You got to admit, it's pretty complicated. How doe it work? How do they do it? Who invented it

2007-03-24 12:33:59 · 6 answers · asked by CuriousSam 2 in Science & Mathematics Engineering

6 answers

You have asked one of the most technically intensive questions anyone has ever asked. The camera does not have color sensors from which it derives the color of the scene that it is receiving. That information is divided out as certain phase signals which are representative of the colors of the light scanned by the camera. While I could go into a lot more detail, it would be best for you to separate out your question into sections, such as how does the camera operate. RCA is a good place to start since they make such cameras. You might also visit a television station and talk to the engineers there. You can also find books if you do a search for them that will tell you all about it. Why answer this way, because I don;t have the time to go into the detail of color burst theory, why we use 3,158 MHz as the control and sync frequency for color television, how the sync separator works in the TV, or how the FM audio signal is separated from the AM carrier wave in analog TV, and those sectional concepts just skim the surface of your question. You need to get a book on it, and give yourself a good day to read and study how it is done, if you want to go in depth with it.

2007-03-24 20:25:44 · answer #1 · answered by Anonymous · 0 0

Since you are using a computer and the internet, i will use those analogies to simplify how a television system works.

Your computer screen is made up of pixels, the computer reads out its video memory to the monitor starting from the top left pixel position and then going across to the end of the line, then working down a line at a time to get to the bottom and then the whole process is repeated to refresh the display. A television camera has light sensitive pixel elements called a CCD array. The camera reads the light value on each pixel in sequence, starting at the top line and working down. These are transmitted to your TV set much like IP packets. Every line starts with a synchronizing pulse which keeps the receiver in step. The TV set then operates just like a computer monitor to make its display, line by line.

The audio is nothing more than FM radio. The channel for the audio is 4.5 MHz above the video carrier. The TV set has an FM radio receiver that tunes to this frequency.

In February 2009, analog television will no longer be used in the USA. The TV pictures and sound will be sent as streams of digital data and the TV set will be even more like a computer monitor.

2007-03-25 14:05:10 · answer #2 · answered by lare 7 · 2 0

If I had a dollar for every time I heard "I think the picture tube is bad", I would be able to retire now. The picture tube is the most reliable part in the whole set (unless it's a Zenith from 8-10 years ago). Have you got the input set for the correct input selection? If you have a satellite, or cable box, is it turned on, and connected correctly? Do you have snow, or just blank screen? On your RCA factory remote, try pressing the button below the digit 7, (input select). See if that helps. If you are using the video input cables, you might have a bad yellow cable. Try changing one of the other (red or white) cables to where the yellow should be connected, that might help. If that proves to be the trouble, the video cables are bad, and must be replaced. I would say, since the menu comes up, the picture tube is okay. If what I have outlined for you brings no help, it's time to call your local RCA repair center. Since it is a 36" I would see about spending a little money with it. These sets are still rather expensive, new. I looked up the specs on this set, there is only one video input on the rear,S-video, and the antenna input. Which are you using? This set is not very old, so I would certainly have it inspected, if the hookups and cables are all okay.

2016-03-17 01:54:38 · answer #3 · answered by Anonymous · 0 0

Let's work on the picture first - when you point that camera at something, the light passes through a lense and is focused on a flat slab behind the lense. That slab has three different color sensors (if you get a magnifying glass and look at your color tv you will see a pattern of color dots as well). The tv signal is generated by a raster pattern so it scans a line of these dots and generates a signal (old TV is analog, HDTV is digital) where the amplitude of the individual dots is proportional to the intensity of the light image - that signal is then amplified, and transmitted as a wave, with the same raster (which means back and forth) at your TV set.. There are several standard TV signals, so TVs made in the US have a different standard than TVs made in Europe, so one won't work well using signals meant for the other. The actual signal is pretty easy to generate - just making the dots line up correctly, and adjusting the three signals to raster correctly at both ends was a bit difficult. Most problems like this involve breaking the problem into little parts, solving the parts, and then building up from those simple parts. Radio started from pretty simple parts, creating dots and dashes from sparks, then added voice by using different modulation methods (transferring the sound wave into an electric signal) then doing things to amplify the signal - making the radio waves more energetic to reach further, etc...)

2007-03-24 13:18:37 · answer #4 · answered by Steve E 4 · 2 0

I would like to ask the same question as the user above.

2016-08-23 21:57:53 · answer #5 · answered by Anonymous · 0 0

It's possible for sure

2016-07-28 10:10:18 · answer #6 · answered by ? 3 · 0 0

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