🚀 go-pugleaf

In article <1923@mts.ucs.UAlberta.CA> userDANC@mts.ucs.UAlberta.CA (unknown) writes:
   Is anyone aware if a scheme exists to 'copy protect' commercial
   VHS tapes?  In running a recent tape through a second video recorder,
   it looked as if the signal had become scrambled, though viewing it on
   a normal television worked fine.  As a second year Electrical Engineering
   student, I would be very curious in learning the details of the protection
   scheme.  (looks like I have a bit of catching up to do).

Yes, there are copy protection schemes for VHS tapes (both NTSC and PAL).
And they are used.

Basically, what they do is mess up the recorded signal in a way that the 2nd
(recording) VCR won't like, but which won't affect TV viewing.  The solution
is to take the composite or RGB signal that's coming out of the 1st VCR and
break it down to RGB + proper syncs and wipe everything else off the signal,
then combine everything up again.

One cheapo solution is to record in RF, but the quality stinks.

These were discussed in quite a lot of detail in Elektor (and they had plans
for a copy-protection remover), the issue number evades me at the moment.
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