The satalite reciever is more or less a reader/writer to the card. Writing can be initiated by the data stream from the satalite. The dynamic code on the card now has the ability to double check it's own hardcoded serial number against the software number that is created when you hack/clone a card. If they don't match up, then card tells the reciever to write certain bytes called "write-once bytes". These bytes are made in the "off" position, but once thay have been turned on, they cannot be turned off. When the reciever writes these byte, which reside in the boot sector of the card, the card is corrupt and pretty much dead in the water.
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The satalite reciever is more or less a reader/writer to the card. Writing can be initiated by the data stream from the satalite. The dynamic code on the card now has the ability to double check it's own hardcoded serial number against the software number that is created when you hack/clone a card. If they don't match up, then card tells the reciever to write certain bytes called "write-once bytes". These bytes are made in the "off" position, but once thay have been turned on, they cannot be turned off. When the reciever writes these byte, which reside in the boot sector of the card, the card is corrupt and pretty much dead in the water.