TW
How can that be? How could transmitters south of London (and there is a lot of the country south of London - Southampton, Brighton, Plymouth....) get a signal if the "daisy chain" was strictly south to north?
Steve in Pudsey posted:
I thought the daisy chain effect was strictly north-south, so a station just north of the border would rebroadcast an English relay?
How can that be? How could transmitters south of London (and there is a lot of the country south of London - Southampton, Brighton, Plymouth....) get a signal if the "daisy chain" was strictly south to north?
BT
No. Under normal conditions, if Glasgow failed you would get the network feed from London in high quality via the usual links. The transmitter site is capable of broadcasting this direct without it going near the BBC in Glasgow.
thegeek posted:
So if something went wrong at Glasgow (say, major power failure, and the generators fail too) and there was essentially no direct feed to any of the Scottish transmitters, would we be left with a fuzzy rebroadcast of BBC NE&C?
No. Under normal conditions, if Glasgow failed you would get the network feed from London in high quality via the usual links. The transmitter site is capable of broadcasting this direct without it going near the BBC in Glasgow.
:-(
A former member
Yes, IIRC the regional/national centres are 'fail-safe' if something happens to them the channels bypass them
:-(
A former member
the rbs kix in in the transmitter goes down and takes an offair feed of the nearest transmitter
i watched the tests last night, great stuff - the picutre went off for 5 seconds then BBC London came in - on BBC Midlands. the picture quality was awful though.
i watched the tests last night, great stuff - the picutre went off for 5 seconds then BBC London came in - on BBC Midlands. the picture quality was awful though.
SP
How can that be? How could transmitters south of London (and there is a lot of the country south of London - Southampton, Brighton, Plymouth....) get a signal if the "daisy chain" was strictly south to north?
yeah I didn' t make too much sense did I lol The transmitters don't take the *nearest* transmitter's feed on RBS, each one has a *specific* transmitter (or perhaps transmitters - Hannington takes Rowridge as its main feed but can also use Crystal Palace) which it can derive a programme feed from. It can't be just *any* neighbouring transmitter because there has to be a receive aerial pointing at it and a receiver tuned into the right frequencies.
This daisy chain radiates outwards from Crystal Palace so for most of the country this holds true. The point was that a transmitter in say Selkirk would rebroadcast one of the NE&C transmitters, possibly Chatton. It wouldn't take a feed from one of the transmitters in Scotland - otherwise during these tests the signal would not get up to the north.
That isn't to say that there isn't a mechanism for an engineer to be able to change it to take a Scottish feed I guess during a specific outage...
Turnbull & Williams posted:
Steve in Pudsey posted:
I thought the daisy chain effect was strictly north-south, so a station just north of the border would rebroadcast an English relay?
How can that be? How could transmitters south of London (and there is a lot of the country south of London - Southampton, Brighton, Plymouth....) get a signal if the "daisy chain" was strictly south to north?
yeah I didn' t make too much sense did I lol The transmitters don't take the *nearest* transmitter's feed on RBS, each one has a *specific* transmitter (or perhaps transmitters - Hannington takes Rowridge as its main feed but can also use Crystal Palace) which it can derive a programme feed from. It can't be just *any* neighbouring transmitter because there has to be a receive aerial pointing at it and a receiver tuned into the right frequencies.
This daisy chain radiates outwards from Crystal Palace so for most of the country this holds true. The point was that a transmitter in say Selkirk would rebroadcast one of the NE&C transmitters, possibly Chatton. It wouldn't take a feed from one of the transmitters in Scotland - otherwise during these tests the signal would not get up to the north.
That isn't to say that there isn't a mechanism for an engineer to be able to change it to take a Scottish feed I guess during a specific outage...
SP
but during the tests you're receiving it via Oxford - this is an artificial situation, RBS will only usually be used one "generation" away
Bob McBignob posted:
the rbs kix in in the transmitter goes down and takes an offair feed of the nearest transmitter
i watched the tests last night, great stuff - the picutre went off for 5 seconds then BBC London came in - on BBC Midlands. the picture quality was awful though.
i watched the tests last night, great stuff - the picutre went off for 5 seconds then BBC London came in - on BBC Midlands. the picture quality was awful though.
but during the tests you're receiving it via Oxford - this is an artificial situation, RBS will only usually be used one "generation" away
GE
Despite being awake at the time, I forgot to tune in the other day - but I seem to recall that last year, the signal from Black Hill wasn't really all that bad. Watchable (as far as a test card can be), but not fantastic. I also managed to get the London edition of Ceefax without too much interference - and NE&C's Ceefax for a short while too.
thegeek
Founding member
Bob McBignob posted:
I hate to think what it was like in Scotland!
Despite being awake at the time, I forgot to tune in the other day - but I seem to recall that last year, the signal from Black Hill wasn't really all that bad. Watchable (as far as a test card can be), but not fantastic. I also managed to get the London edition of Ceefax without too much interference - and NE&C's Ceefax for a short while too.