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Documents about building TV descrambler for US cable TV

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Junior Member level 1
Jun 18, 2001
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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?



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3chip descrambler

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...

3 chip ssavi

I guess what I really want is the descrambler part. I can design and build a channel selector fairly easily.

Thanks anyways

cable decoder schematic

Try your luck here:
**broken link removed**
**broken link removed**

best regards

3 chip descramble


**broken link removed**

I have tested it on ssavi. But it sucks since you must re-sync on every channel.

pic descrambler





I'm looking for a north america cable decoder
pcb soft etc.. the full stuff

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Anybody knows were i found a replacement for CD2240 and CA3126E for TV descramblers

ssavi 3 chips

I think CD2240 is a harris chip. Check Digikey, (I hope you are in North America)

cable descrambler schematics

have also a look at the following link


chip descrambler

Anyone have info one new ntsc digital descrambling?

soft descrambler

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:// 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

pal m descrambler

I agree the pic version is better.

descramble tv

do any of these possibly work with digital systems?

2 chip descrambler with pic16f84

I suggest to browse the following page

**broken link removed**

Interesting info about the 3chip descrambler (pic based) could be found there.

pic mcu + descrambler

fsiuru, i like that page, but if it is yours..... i would like it to continue your good work and do the PAL part signal.


descrambler circuit 3 chip

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 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;

stay tuned (o;

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