BBC One Nightlight - Printable Version

+- Pres Café (https://pres.cafe)
+-- Forum: Pres Café TV and Radio Forums (https://pres.cafe/forumdisplay.php?fid=1)
+--- Forum: Industry News, Technology and Facilities (https://pres.cafe/forumdisplay.php?fid=6)
+--- Thread: BBC One Nightlight (/showthread.php?tid=286)

---

RE: harshy - Jimbo2022 - 06-01-2023

(06-01-2023, 12:08 AM)harshy Wrote:  

(05-01-2023, 11:55 PM)Jimbo2022 Wrote:  12422H SR 27500 FEC 2)3 DVBS QPSK

6411 and 6491 are the same channel - BBC One Nightlight
6417 is BBC News
6481 is BBC Radio Wales
6487 is BBC Radio Foyle

But this mux is hard to pick up on some receivers. There are multiple empty service labels too - IE not on air at present

On the tv channels there’s some black and white lines which aren’t on the regular SD channels.

Is that at the top of the screen? Spotted that but thought it was there anyway

---

harshy - harshy - 06-01-2023

Yeah it’s at the top, it’s not there on regular bbc sd channels.

---

RE: BBC One Nightlight - thegeek - 06-01-2023

when you say black and and white lines, do you mean some sort of attempt at a cue dot?

---

RE: BBC One Nightlight - Stooky Bill - 06-01-2023

Looks fine to me, can't see anything. There seems to be only half of the line at the top of the screen, but that's present on the existing SD versions too

---

harshy - harshy - 06-01-2023

(06-01-2023, 08:29 AM)thegeek Wrote:  when you say black and and white lines, do you mean some sort of attempt at a cue dot?

I’ll attempt a screenshot as I don’t know how to describe it technically

---

RE: BBC One Nightlight - ASnep - 06-01-2023

I think I see what you mean:
 

You can only see them if you turn off overscan on your TV. Maybe some sort of metadata going to whoever is uplinking the channels?

---

RE: BBC One Nightlight - IanJRedman - 06-01-2023

I think I see what harshy is referring to. Look carefully at the very top edge of the video here:

https://twitter.com/a516digital/status/1611081788969058305 

You occasionally see this on SD video if you're watching without any overscan. AIUI, I think we're seeing the very bottom of a timecode running, outside the active picture area. But I'm open to correction on that! I've seen it on Dad's Army repeats on BBC Two HD in the past.

(Sorry, ASnep posted while I was writing this)

---

RE: BBC One Nightlight - IanJRedman - 06-01-2023

Just to answer my own question, I don't think I was right to say it's the 'bottom of a timecode' hiding just outside the frame - I think those lines are the timecode! I think it's either this, or something very similar:

https://en.m.wikipedia.org/wiki/Vertical_interval_timecode 

---

RE: BBC One Nightlight - Spencer - 07-01-2023

I’m sure I remember seeing black and white lines like this at the top left of the screen on some channels in the early days of digital TV.

If I remember correctly, they acted as a l signal for some boxes to switch aspect ratios between 16:9 and 4:3.

---

RE: BBC One Nightlight - Nini - 07-01-2023

Those lines are data being transmitted in the vertical blanking interval, usually no more than a line in the overscan area where it wouldn't be visible to the viewer. In the past it's been used to send things like AR flags, teletext and other data streams like subtitling though rarely timecode. If it's on SD broadcasts it's there for compatibility reasons with old tube televisions. I might be wrong on some of this so you can correct me.

---