Strictly speaking that's not Presfax, as it's not generated on Ceefax-era kit. I guess the name has stuck despite an upgrade...
The name Presfax predated the teletext looking version by many years
That only came about when they moved to the Broadcast Centre, prior to that it was a basic black and white terminal type display. All the suites at TVC had teletext look displays called the SSD, but they didn't leave the building as far as I know.
'Presfax' dates back to the days of the manual galleries for NC1 and 2. There was a Presfax Operator who sat in the gallery entering and updating the information
That's right .. it was a terminal which became a BBC micro whuch sent the data over ITS ( think a but like American CC .. two bytes per tv line per field ..
this covered the Next Junction only
With the Network transmission area NTA ( which had automation ) this was replaced with a Datacast ( packetX/31) system which output an 82 charecter per row black and white display which has count downs being the literal value sent over the new ITS for count in or count out of an item. .... this actually was radiated so OBs could use in ( but did not) and likewise was only next junction
The source if the information was a serial line version if the SSD which was interpreted to make it region friendly
Here my memory fails me but I think the same system was used when Digital transmission area became master ...and NTA closed
With the move up the road to the Broadcast Centre the source was a file in the automation, abs so a new sysytem which had a standard teletext display .
This was in a box which had display cards and a "Hump" whuch had a computer card in it
In London the computer read the file, took in timecode and then generated a set of data which included packet 8/30/1 and 8/30/2 PDC as well as a datacast feed for Presfax on a serial line to the metro databridge /inserter.
The Nations worked likewise without the Presfax output and time could be taken from the incoming network feed going into the cards.
The regional display has a countdown based on comparing the time of the event with the incoming packet 8/30/1 and showed all next items on the screen not just next junction
Ie,( I think)next 10 items.
Because these systems used the NET 1/2 feeds for transport , things were always time aligned no matter how long the network path was .... a year or two back with change if automation PResfax was replaced by SSD over IP network route,
Steve in Pudsey gave kudos