[mythtv-users] 3 tuners in 1 device versus 2 broadcast sources

[James Miller]

The 3-tuner device I'm referencing would be something like the HDHR3-CC: 
it apparently has 3 tuners built into it, but has only one coaxial plug. 
As I understand it, this allows the device to receive up to three channels 
simultaneously from, say, a cable hook-up. So, three people, for example, 
that had TV's that could access (via its ethernet port) the HDHR3-CC, 
could each be watching programming on different channels simultaneously. 
Have I understood correctly how this device works?

If so, let's say someone wanting to use this device has two broadcast 
sources: one ATSC cable, and the other OTA. Since there is only one 
coaxial input on the HDHR3-CC, could one feed both sources using, say, a 
splitter into the HDHR3-CC? Would it somehow be able to sort out how to 
record, using its tuners, from either or both of those sources?

Thanks in advance for any input you may offer to this query.