How were cue dots generated?

I've been meaning to ask this for a while and watching Strike It Lucky just reminded me. It's an odd question but how did cue dots used to be generated? I've noticed especially on shows in the 70s and 80s that they never settle and seem to have a mind of their own. I've seen them change shape, speed, patterns and directions. At the end of SIL tonight, the cut dot sped up, changed direction, came to a stop, then started spinning in the other direction.

I know this isn't a life or death matter but it's something I'd love to know the answer to. How were they generated to make them act so unusually?

They were just electronically generated using a piece of kit that would've been included in the rack of a control room.

I think the speed/direction meant different things such as how long was left and what was coming up next. This may have been automated at times or altered manually using dials/faders linked to the kit itself.

The same kit could generate time codes and such like, and were later developed to signal the aspect ratio of a programme and other hidden details like that.

I presumed the direction was to denote a minute had passed then went it went off in the other direction was the next minute.

Something like this which would be hooked up to a controller on the desk.



http://www.marcotec.ro/media/00000006848.pdf

Now you say that, I think it changed direction with something like 10 or 20 seconds left.

The oscillator that generated the stripes on the 70/80s generators was just a free running device, and deliberately not locked to the input genlock , so that it did randomly 'rotate'. This made the inserter cheaper
to manufacture ! and the cue dot was generally more noticeable because of that..

Later versions I've seen, employ the stripes rattling from side to side at a constant speed.

As Markymark has said the dots were simply an on-off indicator. The speed and direction were just incidental because they chose a cheap solution to implement them - and the movement probably made them more obvious. They were usually added downstream of the vision mixer with a simple switch controlled box. When SISLive (formerly BBC OBs) bought O21 (formerly an ITV OB company) one of the big differences was that the O21 trucks had a panel on the front desk to trigger the cue dots!

The BBC's cue dots (which were used to signal in the opposite direction to ITV's) were usually static. (*)

(*) ITV used cue dots from the studio or OB to signal to the various ITV play out areas that a break was imminent. The BBC used cue dots on off-air added by the presentation play out area to signal to the next live studio or OB that they were about to go on-air. The BBC stopped using cue dots from Presentation when digital TV started (because the delay in off-air meant it was no longer an accurate time signal) They are now only regularly used by the BBC at Wimbledon, to signal to other broadcasters when a court feed is about to switch from a multilateral clean world feed to a unilateral dirty domestic feed. (i.e. the BBC are about to use the court facilities for an interview that will appear on the output)

With a recorded programme like Strike It Lucky they have been added in the edit suite or during the recording?

I'm sure I read somewhere a cue dot, when it disappeared from the broadcast, was a seven second run-up to whatever was going to happen next. The recent Strike It Lucky reruns only seem to have up to five seconds (though I suspect Fremantle might have had something to do with that).

I also notice on some Take Your Pick reruns on Challenge with regards to cue dots, they seem to have a mind of their own, randomly appearing on some shots and not others.

I guess the edit suite but not 100% sure on that. I've had a look at some of my old recordings and noticed a cue dot appearing in a certain point of a trailer for take the high road. Interesting how the cue dots were burned onto the master tape in those days. Also by being a BBC1 Scotland viewer the cue dot would not be shown over the ident as there would be no need for it as they were not "cueing" anyone.

Here's one of the examples I referred to. You see two cue dots in this clip. The first the live cue dot for the end of emmerdale but at 32 seconds we see another briefly appearing during Scottish TV's Take The High Road trailer. The brief appearence presumably being on the scene that is on prior to the commercial break.
http://m.youtube.com/watch?v=UmACVLb22Sw

Could this be because the programme has been edited since original broadcast with footage from earlier/later in the episode inserted where it wasn't originally meant to be?

An obvious example of this can be seen in the Challenge[TV] showing of Winner Takes All...
http://www.youtube.com/watch?v=aQcmtBcjkcs&t=24m15s

You can see that the shot at 24:20 (sans cue dot) is reused again towards the end of the episode at 25:04 when the rather odd looking cue dot should be on screen. This makes the contestant look rude because he seems to be shrugging his shoulders and turning his nose up at Jimmy Tarbucks kind words. The audio doesn't seem to be edited so whatever they edited out must have been visual only. Viewers who don't notice the edit are left with the impression that Mr Phillip Hardingham is very rude indeed whereas viewers who did notice the edit must assume that he got his bum out or something. Either way, he should sue Challenge[TV], Yorkshire Television and/or Flextech (delete whichever entities no longer exist) for besmirching his character.

For the record, he also went on to appear on the first ever episode of Krypton Factor the following year (source A, Source B - I think that is him on the left of the picture as the lights come on.) and lost a game of Countdown in 1987 (source).

He would be 59/60 years old now. I hope he Googles his name one day and finds this post. He can let us all know what was cut out from his appearance on Winner Takes All and how it has effected his life since.

EDIT : Further research reveals that he also appeared on and won Brain of the Border (whatever that is) and 15-1 (source) in 2000.

Cue dots were also used regularly by BBC NI, during the days of separate analogue/digital versions of BBC Two NI in the evenings, to identify and check that control of the channel had successfully been split from one to two pres suites. The dots were simply generated on as Aston page and keyed on the pres mixer. They are still occasionally used to identify sources / confirm that routing or switching has been successful.