[mythtv-users] Two tuners showed up

[joe at thefrys.com]

indeed, multirec means recording multiple shows on the same 'broadcast channel' (laymans terms)

For example, my cable company manages to squeeze 9 to 11 SDTV channels on one catv channel (a multiplex).   When I chose to watch any of those 11 channels, the data for all 11 arrives at my card and it only passes the one I am interested in to the rest of the system.  With Multirec on, the tuner simply passes more of the data.  

I have recorded as many as 5 shows concurrently from that one multiplex (never wanted more than that).

You see the same thing in broadcast.  Most channels share a multiplex with others, the bandwidth of a standard NTSC channel is wide enough for 2 HD, and 4 or more SD channels multiplexed.
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