Teletext and to pad out the fixed packet. The vertical caption position is determined by the packet address. In the case of the Ceefax and ORACLE systems and their successors in the UK, the teletext signal is transmitted as part of the ordinary analog TV signal but concealed from view in the Vertical Blanking Interval (VBI) television lines which do not carry picture information. The teletext signal is digitally coded as 45-byte packets, so the resulting rate is 7,175 bits per second per used lines (41 7-bit 'bytes' per line, on each of 25 frames per second). A teletext page comprises
S-VHS can be recorded along with the normal video signal. As a result, this teletext data is also able to be decoded and displayed on-screen as an overlay of the conventional TV picture (though not on standard VHS machines). A suitably teletext-equipped receiver/decoder (TV, PC card, etc.) displays the recorded teletext data information as if the video were being viewed as a real-time live broadcast. S-VHS video cassette recorders (VCRs) and cassette tapes are nearly identical in appearance and operation, and backward compatible with VHS. Older VHS VCRs cannot play back S-VHS recordings at all, but can record onto an S-VHS