Seeking Scrambled Sky TV Footage (VideoCrypt) — Archival/Technical Project

R

Robo666

New Member
My Satellite Setup
SkyQ
My Location
Wales
Hi all,


Back in 1996/97, I built a software-based visual decoder that could unscramble Sky’s analogue satellite signal (VideoCrypt) in real time using a PC, a BT848 TV card, and some clever processing.


It didn’t use or interact with smart cards — instead, it worked by visually undoing the "cut and rotate" scrambling applied to each scanline of the signal.


I recently found my original software on an old hard drive and I’m now working to rebuild the setup using period hardware, purely for archival and demonstration purposes.


To move forward, I’m looking for off-air recordings of Sky broadcasts while still scrambled — ideally:


  • Before a decoder was applied (recorded directly from the dish)
  • With no valid card (clean VideoCrypt scrambling preferred; "insert card" overlays still useful)
  • From Sky Movies, The Movie Channel, Sky Sports, etc. — ideally around 1993–1998

This isn’t about breaking card encryption — it’s about real-time visual reconstruction of the image by reversing the analogue scrambling process, much like early pirate decoders.


If you have any old VHS tapes or digital captures of scrambled Sky analogue broadcasts, please get in touch — I’d love to hear from you.


Thanks for reading,
—Rob
 
Such recordings are not easy to find, especially in the UK as these had almost invariably been passed through the decoder.

When such transmissions had been passed through the decoder with no valid vard, the image was effectively double-scrambled as the decoder used the wrong seed to try to descramble the image. Such recordings are pretty useless as the software decoder would need to be pretty clever to undo the two cuts (first by transmission chain and the second by the decoder).

I do have a capture of such a recording from VHS, which had then been descrambled offline by a real decoder, around 25 years later! A heck of a time-shift. The small section is attached but I do have the original 9GB file, if you want to try decoding it from scratch.. and maybe decode colour too. This is from The Adult Channel, so download at your own risk, given the material.

 
Captain Jack said:
Such recordings are not easy to find, especially in the UK as these had almost invariably been passed through the decoder.

When such transmissions had been passed through the decoder with no valid vard, the image was effectively double-scrambled as the decoder used the wrong seed to try to descramble the image. Such recordings are pretty useless as the software decoder would need to be pretty clever to undo the two cuts (first by transmission chain and the second by the decoder).

I do have a capture of such a recording from VHS, which had then been descrambled offline by a real decoder, around 25 years later! A heck of a time-shift. The small section is attached but I do have the original 9GB file, if you want to try decoding it from scratch.. and maybe decode colour too. This is from The Adult Channel, so download at your own risk, given the material.

Click to expand...
My software will work, it will restore the image as it just rotated it in the wrong place twice. I've seen some on youtube but getting that back to a composite video would be difficult. But those files are good quality image. so it may work.
 
My capture is without the decoder in place, so it's just single scrambled - should be nice and easy.

I'll PM you the link to the full 2 hour capture, though only half of it is scrambled.
 
Captain Jack said:
My capture is without the decoder in place, so it's just single scrambled - should be nice and easy.

I'll PM you the link to the full 2 hour capture, though only half of it is scrambled.
Click to expand...
That would be great thanks. Would be nice to see it working again.
 
I'm curious to see the results of a decrypted VHS recording. Could you please post a screen capture here if you get it working? I was thinking the resolution of a VHS recording is going to half the number of lines in the video, and therefore blur the nearby lines into each other, so wouldn't that make it difficult to stitch back together?

I remember many of my old Sky setups used to have annoying faint moving horizontal lines in the decoded picture, which I assumed was coming from the decoder, as clear channels didn't suffer from this issue. I wondered if similar results would show up on old decoded VHS recordings.
 
timo_w2s said:
I'm curious to see the results of a decrypted VHS recording. Could you please post a screen capture here if you get it working? I was thinking the resolution of a VHS recording is going to half the number of lines in the video, and therefore blur the nearby lines into each other, so wouldn't that make it difficult to stitch back together?

I remember many of my old Sky setups used to have annoying faint moving horizontal lines in the decoded picture, which I assumed was coming from the decoder, as clear channels didn't suffer from this issue. I wondered if similar results would show up on old decoded VHS recordings.
Click to expand...
Check the videos from post #2 from 28sec - the decoded colour is no longer colour. And yes, it's a mass of faint lines..
 
Captain Jack said:
Check the videos from post #2 from 28sec - the decoded colour is no longer colour. And yes, it's a mass of faint lines..
Click to expand...
Oops. Sorry, I did read your post yesterday but forgot to download the files... :wacko:

I had similar lines like that on my (legitimately!) decoded VideoCrypt channels but not as severe and the picture was in colour. Never did figure out how to fix it. While the analogue days where much more fun I don't miss those annoying lines.
 
Progress. Wish i Had 200FPS back in the day! The software would also scramble a unencrypted feed and generate a pseudo videocrypt. ordered a HDMI to RCA Adapter so i can take a feed from youtube. i'll also save you ones you sent to VHS

@Captain Jack Thanks.
 

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