smb@ulysses.UUCP (Steven Bellovin) (05/16/84)
Can one use a VCR to record a scrambled signal, then play it back later through the cable company's converter? Or does the recording process depend on accurate recognition of sync signals, etc.? cable ---> VCR ---> converter/unscrambler ---> TV I'm aware of other solutions, such as using a block converter between the cable jack and the VCR; my interest is primarily academic.
fish@ihu1g.UUCP (Bob Fishell) (05/16/84)
(oo) Two of the major encoding schemes, sine wave encoding and synch inversion, are not compatible with the synchronization circuitry in a VCR. The VCR's servo control, which keeps the heads synchronized with the frames of the picture, depends on a good, undistorted synch pulse to prevent rolling and blackouts. This is what add-on "synch stabilizers" take care of; they reshape the synch pulse sort of like a Schmitt trigger. -- Bob Fishell ihnp4!ihu1g!fish