jonesypeter
Posts: 108
Joined: Fri Aug 02, 2013 3:07 pm

TV Hat - Multiple Recordings

Mon Nov 05, 2018 8:56 pm

I have series recordings set-up on TVHeadend and on Sunday I was recording one film on ITV2 which started at 20:00 and went onto 22:00, and another programme on ITV3 which ran from 21:00 to 23:00.

Both programmes seem to have recorded perfectly despite the 1 hour overalap? I had assumed you would need multiple tuners to do this sort of thing? How does this work?

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rpdom
Posts: 16722
Joined: Sun May 06, 2012 5:17 am
Location: Chelmsford, Essex, UK

Re: TV Hat - Multiple Recordings

Mon Nov 05, 2018 9:11 pm

Several channels are broadcast on each frequency. The data is multiplexed together. The headend software extract the required channel from the datastream. If two channels are in the same datastream they can both be extracted at the same time. The top BBC and ITV channels all share a frequency.

mikerr
Posts: 2816
Joined: Thu Jan 12, 2012 12:46 pm
Location: UK
Contact: Website

Re: TV Hat - Multiple Recordings

Mon Nov 05, 2018 9:14 pm

You can record multiple channels if they are on the same mux (multiplex)

It's a single tuner which can only access one mux at a time, but one mux can host dozens of channels:

Freeview has 5-6 muxes with dozens of channels on each one.
E.g PSB2 has ITV2 and ITV3

https://ukfree.tv/transmitters/multiplexes
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