Advances in teletext decoder design

The author reviews the types and uses of the teletext services available. He then introduces the latest decoders, compares their architecture with that of previous designs, and explores some of their features. Specifically, he considers two third-generation decoder designs, IVT and DVT, which are being introduced to cover the lower and higher ends of the market, respectively. He notes that set manufacturers can substantially reduce the cost of incorporating teletext in their TV sets by using the single-chip integrated VIP and teletext (IVT) decoder, which integrates the data-slicing function with the rest of the decoding circuitry. The author also considers the digital video text (DVT) decoder, which has improved page acquisition and display performance, for use in TV sets with standard or double line frequency scanning