The TV Question Amnesty Thread: A thread to ask questions about things you want to know about television but were too afraid to ask - Page 28

IS

Inspector Sands 22 October 2020 12:21pm

There's a film buried within Youtube showing just that, including interviews with the CEGB staff discussing it at a power station. I'm afraid I can't find it at the moment - it was very pertinent to your question and interesting. Sometime in the 1970's I think, lots of Brylcreem.

Here's a recent video of 'TV pickup' in the National Grid control room

MA

Markymark 22 October 2020 1:09pm

Inspector Sands posted:

Here's a recent video of 'TV pickup' in the National Grid control room
https://www.youtube.com/watch?v=slDAvewWfrA

Having sat in many design meetings to discuss the detailed layout of monitor stacks in studio galleries, OBs, and MCRs, the notion you have to turn round to look at any monitor seems way off any scale of acceptability !

BL

bluecortina 22 October 2020 1:12pm

Inspector Sands posted:

bluecortina posted:

There is some information here.

https://www.theguardian.com/media/2007/aug/02/itv.broadcasting1

I think the initials stood for the Independent Television Film Company but I'm not absolutely certain.

Not sure if they changed the name as they stopped dealing with as much film, but it was Independent Television Facilities Centre
https://www.thetimes.co.uk/article/now-read-this-subtitles-for-sale-q97mjbrk0b5

Independent Television Facilities Centre does sound a more accurate name. I think it's been around the block a few times, I think at one point it was owned by Deluxe (maybe it still is, I'm afraid I can't view your link as it is behind a paywall).

Edited to add, some local telecine departments had a more 'biting' expansion on the letters ITFC but it would not be appropriate here.

TI

TIGHazard 22 October 2020 1:20pm

Markymark posted:

Inspector Sands posted:

I was once told that a TV stations logs have been asked for by the police in the past. There have been cases where a witness has said, for example, that they heard the gunshot while the credits to EastEndera were playing. They have then gone to the BBC and asked what time exactly they went out.

I'd have thought it's still the same but once automation came in, it was that that generated the 'as run log' of what went out. When I worked in pres the schedules were imported into the playout automation, but then at the end of a day the automation sent what actually went on air back to the scheduling system.

One use of this of course is that the scheduling software kept track of how many times things went out, so if the director swapped out a trail or played a filler that wasn't scheduled then those assets would be updated

I was surprised visiting the National Grid Control Centre about 15 years ago that their method of monitoring when a big ticket programme on BBC 1 or ITV was about to end, or go into a break were two off air fed portable tellies on the desk. I think I've asked this before but how difficult would it have been for Red Bee etc to supply them with a schedule run down ? Seems an inappropriate method to let a billion gallons of water loose at a hydro electric power station in Wales, to deal with Corrie's centre break ?!

I think only us (and Ireland) have such a tea habit that it causes this phenomenon. Because our electric kettles are much more powerful than those in the rest of the world - 3000 to 4000W compared to 500 to 1000W, the amount of people switching on kettles all at once during a single ad break or at the end of a programme can actually cause cascading failure across the national grid network as the voltage drops. So they need to keep an eye on ad breaks and the end of shows to keep the grid running.

I can only imagine the cursing that occurred about 12 years ago when Strictly managed to end 10 minutes earlier than billed.

MA

Markymark 22 October 2020 1:26pm

TIGHazard posted:

Markymark posted:

Inspector Sands posted:

I was once told that a TV stations logs have been asked for by the police in the past. There have been cases where a witness has said, for example, that they heard the gunshot while the credits to EastEndera were playing. They have then gone to the BBC and asked what time exactly they went out.

I'd have thought it's still the same but once automation came in, it was that that generated the 'as run log' of what went out. When I worked in pres the schedules were imported into the playout automation, but then at the end of a day the automation sent what actually went on air back to the scheduling system.

One use of this of course is that the scheduling software kept track of how many times things went out, so if the director swapped out a trail or played a filler that wasn't scheduled then those assets would be updated

I was surprised visiting the National Grid Control Centre about 15 years ago that their method of monitoring when a big ticket programme on BBC 1 or ITV was about to end, or go into a break were two off air fed portable tellies on the desk. I think I've asked this before but how difficult would it have been for Red Bee etc to supply them with a schedule run down ? Seems an inappropriate method to let a billion gallons of water loose at a hydro electric power station in Wales, to deal with Corrie's centre break ?!

I think only us (and Ireland) have such a tea habit that it causes this phenomenon. Because our electric kettles are much more powerful than those in the rest of the world - 3000 to 4000W compared to 500 to 1000W, the amount of people switching on kettles all at once during a single ad break or at the end of a programme can actually cause cascading failure across the national grid network as the voltage drops. So they need to keep an eye on ad breaks and the end of shows to keep the grid running.

Yes indeed (Point of Order, 3kW is the largest (100% resistive) load you can 'legally' have via a 13amp plug (230v x 13a= 2,990 watts) .
I suspect it stems from the British 'let's have a cuppa' culture too ?

JA

james-2001 22 October 2020 1:40pm

Certainly when I'm staying with my friends in the US, their kettle seems intolerably slow, it's something like 1.5kW. Obviously with 115v there's even less wattage you can get through a plug (though I think the maximum is 15A over there compared to 13A here).

Though I don't think electric kettles are that common over there anyway.

MA

Markymark 22 October 2020 1:58pm

james-2001 posted:

Certainly when I'm staying with my friends in the US, their kettle seems intolerably slow, it's something like 1.5kW. Obviously with 115v there's even less wattage you can get through a plug (though I think the maximum is 15A over there compared to 13A here).

It will be slow, their mains voltage is too pathetically low to enable such things to operate properly. (I^2)R and all that also comes into play......

I think some large US appliances (cookers, heaters etc) can be connected across two phases ? (i.e 200volts)

IS

Inspector Sands 22 October 2020 2:08pm

Yes the US supply is 220v but split across two phases so most outlets get 1 phase, but higher power appliances get both

MA

Markymark 22 October 2020 2:13pm

Inspector Sands posted:

Yes the US supply is 220v but split across two phases so most outlets get 1 phase, but higher power appliances get both

What are the US's official voltage values ? 220v/root3 = 128 volts single phase ?

Edit: Oh, they use 3ph 4wire there
https://ctlsys.com/support/electrical_service_types_and_voltages/

BL

bluecortina 22 October 2020 2:33pm

Markymark posted:

Inspector Sands posted:

Yes the US supply is 220v but split across two phases so most outlets get 1 phase, but higher power appliances get both

What are the US's official voltage values ? 220v/root3 = 128 volts single phase ?

Edit: Oh, they use 3ph 4wire there
https://ctlsys.com/support/electrical_service_types_and_voltages/

Did you know that a long, long time ago someone produced a graph of the voltage of long distance electricity transmission versus cost? The cost (y axis) goes up and down in a cyclic pattern versus transmission voltages along the x axis. How this was arrived at I do not know but I clearly remember it as I used to work in the power cable industry.

The x-axis voltages corresponding to minimum overall cost was 11kV, 33kV, 66kV, 132 kV and this is what we adopted in the UK. But there were also cost dips at 22KV, 44KV, 88KV etc and these are the voltages used in the US. Not many people know that.

MA

Markymark 22 October 2020 2:54pm

bluecortina posted:

Markymark posted:

Inspector Sands posted:

Yes the US supply is 220v but split across two phases so most outlets get 1 phase, but higher power appliances get both

What are the US's official voltage values ? 220v/root3 = 128 volts single phase ?

Edit: Oh, they use 3ph 4wire there
https://ctlsys.com/support/electrical_service_types_and_voltages/

Did you know that a long, long time ago someone produced a graph of the voltage of long distance electricity transmission versus cost? The cost (y axis) goes up and down in a cyclic pattern versus transmission voltages along the x axis. How this was arrived at I do not know but I clearly remember it as I used to work in the power cable industry.

The x-axis voltages corresponding to minimum overall cost was 11kV, 33kV, 66kV, 132 kV and this is what we adopted in the UK. But there were also cost dips at 22KV, 44KV, 88KV etc and these are the voltages used in the US. Not many people know that.

It's a fascinating topic. Last week I drove past a location where they are putting 440kV lines underground. It looked like a motorway or HS2 being built ! Led me to google the subject, and I spent hours reading up on the engineering of such things....

(Sorry about of off topic stuff, I'll stop now)

TE

Technologist 22 October 2020 5:26pm

Inspector Sands posted:

Markymark posted:

I was surprised visiting the National Grid Control Centre about 15 years ago that their method of monitoring when a big ticket programme on BBC 1 or ITV was about to end, or go into a break were two off air fed portable tellies on the desk. I think I've asked this before but how difficult would it have been for Red Bee etc to supply them with a schedule run down ? Seems an inappropriate method to let a billion gallons of water loose at a hydro electric power station in Wales, to deal with Corrie's centre break ?!

Wasn't there a story about one of the BBCs heads of channel or presentation having a Presfax decoder at home, if so it probably wouldn't have been an issue for them to have one too. The later teletext based one I assume didn't make it out on air, the current equivalent is web based so possibly not that difficult to let it escape.

As for ITV, I don't think there was an equivalent. Channel 4 had one but until recently they probably weren't interested in their smaller audiences

The ITS based and the first Datacast monochrome Softel decoder PresFax both were universally recievable ( all be it the Datacast one was sort of scrambled but OBs had receivers and the ITS needed special hardware to Receive) but both used ITS for a real time countdown that may have been a guide that it was end if programme.
With the BBC stopping commercial Datacast services and the need to prove that VBI was being used efficiently otherwise they would take it away (both in tv and RDS data space in radio....) . PresFax the second colour Teletext font MRG decoder data was never emitted..... it lived in the outgoing network feed with national /London flavour of Ceefax .

on the matter of RedBee feeding a nation grid control a "PresFax" for all Major channels ... it was possible but far from straightforward.
Not helped by very few understanding how this part if playout systems worked ... but MRG systems could have made something including displays