Basically, two decoders* are linked to work under a single subscription.
Each decoder is independently connected to the satellite dish and each decoder
has a smartcard. In the Extra View installation, one decoder is designated as
the “primary” decoder and the other one is designated as the “secondary”.
The decoders are linked by a cable that allows communication between them
and the primary decoder sends a “heartbeat” to the secondary decoder via
this cable. If the cable is removed or the “heartbeat” lost, the secondary
decoder will lose video & audio until the cable is replaced or the “heartbeat”
resumed. There is no impact to the primary decoder if the cable is disconnected.