Improvements in or relating to the decoding of signals.

摘要

Figure 4 shows a conventional decoder 24 for the decoding of received satellite television signals relayed from a satellite (not shown) . A card multiplexer 25 holds up to four authorisation cards in slots, 26, 27, 28 and 29. The choice of authorising card from which authorising data is sent to the decoder 24 can be made by manually depressing the correct push button (not shown) on the multiplexer 25. Alternatively the choice of card can be made using a remote control handset (not shown) . The decoder 24 has a "dummy" card 30 inserted in its conventional card slot which dummy card is connected via a flat cable (not shown) to the multiplexer. <IMAGE>