In message <200003051815.KAA03627@mailhost.cmc.net>, John Pearson writes >I don't understand how satalite dish systems work: > >I have a reciever into which I insert a card. What is on the card? The cards usually contain a microprocessor (many used the PIC16C84, which is available built in a card). The later cards in the UK now also contain an ASIC (Application Specific Integrated Circuit), this does some of the work in hardware - preventing pirate cards from being available, as software only isn't fast enough. Put simply the encryption systems usually work by cutting each line of the picture at one or more points, the cut sections are then rearranged before transmission. The decoder in the receiver has to cut at the same places and put them back in the correct order, the subscription card gives the decoder details where to make the cuts based on a seed value sent on the transmission!. >How does the dish service discontinue my subscription if I don't pay my >bill? Your card is individually addressable, if you don't pay they just turn it off - in some cases even having the card out of the receiver won't help, as some systems have to update the card at regular intervals, so it would be disabled anyway. -- Nigel. /--------------------------------------------------------------\ | Nigel Goodwin | Internet : nigelg@lpilsley.demon.co.uk | | Lower Pilsley | Web Page : http://www.lpilsley.demon.co.uk | | Chesterfield | Official site for Shin Ki and New Spirit | | England | Ju Jitsu | \--------------------------------------------------------------/