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Does anyone have any literature on building a tv descrambler for USA cable TV. A circuit would be nice.
I think the sync signal is removed, so what can i do to reconstruct it back?
any ideas?
Hi
There are 2 parts on your decoder.
The channel selector and the descrambler.
You get what you paid for, so the selector knows what is opened or closed.
If you select a closed channel, it will probably blink and say No No pal.
The easyest thing is to buy the cheapest cable selector you can find, those that only gets a channel and put it out on channel 3 or 4. Then you connect the output of this dumy to your selector. Place your selector on channel 3 or 4 and enjoy. I think it must be sufficiently stupid not to notice. And channel 3 or 4 must be a valid (open) one, so it will descramble it nicely to you.
But you must use a very dumb selector. Using your vcr will notdo, because it tries to reconstruct the missing h/v signals.
You may also reprogram the eeprom inside your receiver, or just cut the line that blanks the descrambler.
There are lots of solutions...
try astalavista.box.sk
If you are going to build a board yourself, I would suggest the pic based approach. I first tried the color-burst pll sync regenerator circuit from Graf's TAB series book and then an early 3*chip pic based solution h**p://members.rotfl.com/dturner/. I do remember having to play with the agc cap in my vcr's tuner which was kind of a pain, but I would guess that this been solved by now. After having fun with it, I found it worthwhile to just buy a cheap ca*ble dec*oder box (many of which have the pic solution). The box is nice because it has a tuner and video/audio and channel 3/4 outputs. Good Luck
Well...just started the PAL PIC project as well here in Finland since more and more people here in our company get Cable-TV at home (o;
Hope to get a sample VCXO this week from jauch.de which was said to work perfectly (o;
With a normal XTAL circuit you get really good picture for TCM/Cartoon and Cinema1000. The others have a wavy picture and some brighter parts in the middle of the picture. Those channels don't give a picture at all when fed by a VCR.
Think the PIC soft needs some Scandinavian updates (o;
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