Quote:
Originally Posted by epsilon
If you look at this one you will get a better perspective. https://www.digitalbitrate.com/dtv.p...ive=47&lang=en
They do seem to have been experimenting with 5 stat-muxed channels alongside the fixed bitrate local channel but have rolled back to 4 stat-muxed services with today's changes. I would hope that having 5 stat-muxed channels was a configuration error as that many services on a QPSK mux would be very bad. They could convert to QAM-64 to add more services (as the GMUX did) but that would make the signal far less robust and severely reduce the coverage areas of the multiplexes. They won't be allowed to reduce the coverage areas for local TV so that is a non starter. |
I had another look at this with a better view of events as the new channel mix pattern emerged. The earlier pattern noted on the Emley Moor bitrate graph doesn't really show an experimental combination of 5 stat-muxed channels. If anything, on a single scan, it seems that all of the channels normally stat-muxed were running at fixed bitrate and a much lower rate than would be needed to produce a reasonable quality output. So, I'll put that down to either a configuration error with the signal or with the DBR monitor. The second anomaly simply showed the GREAT! tv channel disappearing and being replaced by null packets. An indication that GREAT! tv had already been replaced with POP in the stat-mux at the Comux NOC but the SI data hadn't been updated to "extract" the new service for the transmitter sites. Quite messy really. But they don't seem to have had any more than 4 channels in the stat-muxed segment at any point in time.