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Reactivate a disabled decoder using VCR !!!

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SphinX

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Hi,

The command packets(like on command) exist in the VBI of the video signal.

I have idea.
When i subscribe first time i record the encrypted channel on a tape using VCR.

Then when the decoder had disabled i playback the tape to reactivate the decoder again.

Does this will work ?
 

flatulent

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It all depends

Record and playback is a common trick. The common way to counter this is to have a time stamp on the signal. The box has an internal clock that keeps track of time. If the box notices a sudden change of time between the activation signal and the encoded program source/local internal clock, it will not allow it.

You can try it, but I expect that it will not work.
 

flatulent

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wrong link

Your link does not go anywhere. Do a google.com search on the part number you describe and you will learn a lot about it and encrypting.
The battery is usuallly for keeping the clock/calendar working.
 

klug

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Hi,

I do not know your type of video scrambling, but as a rule in analog systems they are changing sync pulses and positive/negative polarity of modulation. As a result there are problems in TV-set to receive this signal directly without distortions in IF/demodulator for some error in AGC. To avoid this you need special circuit to catch AGG level during VBI and hold it for all frame. So, you need at least changing of rx stage in your VCR.

Suppose you get videosignal directly from decoder demodulator. You will face other problems: VCR needs clear sync pulses to write signal on tape. You will get scrambled signal with non-standard sync pulses. So, your VCR will not write this signal correctly, and you will have no possibility to playback this signal again.

Other problem is that your SVR possibly is not writing information during VBI, so it will not write digital access code even if signal would be with standard sync pulses.

73! klug.
 

johnyaya

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The Dallas DS5002FP is a secure processor, 8051 compatible. The program is stored in SRAM (hence the battery). The bootstrap loader is the only thing stored in ROM.
 

turttle

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Besides of other issues, I think you would have the same situation as with teletext signal: it's recorded together with the tv video signal but the recorded signal haven't enough quality as to be properly decoded as digital data (I only can see partial teletext info in my recorded VHS tapes). The same problem to post-decode scrambled-video recorded tapes.

No problem about syncs with advanced digital based systems as Nagravision or Videocrypt since the security rely on scrambling the line content and not video-frame signal.

Cheers ;-)
 

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