A Sky, cable and digital tv forum. Digital TV Banter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » Digital TV Banter forum » Digital TV Newsgroups » uk.tech.digital-tv (Digital TV - General)
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

uk.tech.digital-tv (Digital TV - General) (uk.tech.digital-tv) Discussion of all matters technical in origin related to the reception of digital television transmissions, be they via satellite, terrestrial or cable. Advertising is forbidden, with no exceptions.

700 MHz clearance starts March 1



 
 
Thread Tools Display Modes
  #21  
Old February 5th 17, 10:29 AM posted to uk.tech.digital-tv
Jim Lesurf[_2_]
external usenet poster
 
Posts: 4,228
Default 700 MHz clearance starts March 1

In article , Ian Jackson
wrote:
In message , Mark Carver
writes
On 04/02/2017 17:30, Brian Gaff wrote:
Will not all this cramming into the one part give lots of problems
when another uhf lift occurs though? The whole idea of using
frequencies a long way apart at nearby locations was to stop this
problem happening.


Yep, there will be inevitably be a reduction of protection ratios, and
therefore more 'downtime' during lift conditions.


Does digital need so great a protection ratio?


With analogue, you can start seeing co-channel at around -45dB. With
digital, surely it's a lot less (-20dB?) - but it's a case of 'now see
the wanted picture - now you don't'.


Which prompts me to wonder if people will be more likely to get problems
due to the constant 'need' presented to the user to 're-scan' for every
added vacuous shopping channel, etc. Lower near/far TX ratios might
increase the chance of RXs choosing/using the 'wrong' TX and being more
sensitive to reception problems.

When there is a change, our TV tells us a 're-tune' is needed when switched
on. If we choose to not 're-tune' it tells us again every time it is
swiched on until we do a 're-tune'. So despite not being interested in the
actual changes or needing the wonders of yet another crap station we end up
being nagged into re-tuning. Can't find any way to tell the TV to stop this
behaviour.

(Fortunately, our other systems don't give this problem and do what we
decide without nagging or being a PITA.)

Our TV scans and finds both Durris and Angus. But refuses to give any
choice as to which one will be used for any mux. Nor does it seem to
indicate what Mux you're using when watching a station. How typical is
this?

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

  #22  
Old February 5th 17, 12:59 PM posted to uk.tech.digital-tv
Woody[_5_]
external usenet poster
 
Posts: 1,802
Default 700 MHz clearance starts March 1


"Jim Lesurf" wrote in message
...
In article , Ian Jackson
wrote:
In message , Mark Carver
writes
On 04/02/2017 17:30, Brian Gaff wrote:
Will not all this cramming into the one part give lots of
problems
when another uhf lift occurs though? The whole idea of using
frequencies a long way apart at nearby locations was to stop
this
problem happening.

Yep, there will be inevitably be a reduction of protection ratios,
and
therefore more 'downtime' during lift conditions.


Does digital need so great a protection ratio?


With analogue, you can start seeing co-channel at around -45dB.
With
digital, surely it's a lot less (-20dB?) - but it's a case of 'now
see
the wanted picture - now you don't'.


Which prompts me to wonder if people will be more likely to get
problems
due to the constant 'need' presented to the user to 're-scan' for
every
added vacuous shopping channel, etc. Lower near/far TX ratios might
increase the chance of RXs choosing/using the 'wrong' TX and being
more
sensitive to reception problems.

When there is a change, our TV tells us a 're-tune' is needed when
switched
on. If we choose to not 're-tune' it tells us again every time it is
swiched on until we do a 're-tune'. So despite not being interested
in the
actual changes or needing the wonders of yet another crap station we
end up
being nagged into re-tuning. Can't find any way to tell the TV to
stop this
behaviour.

(Fortunately, our other systems don't give this problem and do what
we
decide without nagging or being a PITA.)

Our TV scans and finds both Durris and Angus. But refuses to give
any
choice as to which one will be used for any mux. Nor does it seem to
indicate what Mux you're using when watching a station. How typical
is
this?



Your TV is too old Jim, most modern TVs ask which region you want at
the end of an auto-tune - assuming there is a difference between the
output of the stations it has found.

Best option is manual tune it, then you will know.
Angus is 60, 53, 57*, 54, 58, 49, 31*, and 37* so almost all will have
to move.
Durris is 28, 25, 22*, 23, 26, 29, 32*, and 35* which won't need to
move.
Stations asterisked are HD.


--
Woody

harrogate3 at ntlworld dot com


  #23  
Old February 5th 17, 01:14 PM posted to uk.tech.digital-tv
Ian Jackson[_6_]
external usenet poster
 
Posts: 48
Default 700 MHz clearance starts March 1

In message , Woody
writes

"Jim Lesurf" wrote in message
...
In article , Ian Jackson
wrote:
In message , Mark Carver
writes
On 04/02/2017 17:30, Brian Gaff wrote:
Will not all this cramming into the one part give lots of
problems
when another uhf lift occurs though? The whole idea of using
frequencies a long way apart at nearby locations was to stop
this
problem happening.

Yep, there will be inevitably be a reduction of protection ratios,
and
therefore more 'downtime' during lift conditions.


Does digital need so great a protection ratio?


With analogue, you can start seeing co-channel at around -45dB.
With
digital, surely it's a lot less (-20dB?) - but it's a case of 'now
see
the wanted picture - now you don't'.


Which prompts me to wonder if people will be more likely to get
problems
due to the constant 'need' presented to the user to 're-scan' for
every
added vacuous shopping channel, etc. Lower near/far TX ratios might
increase the chance of RXs choosing/using the 'wrong' TX and being
more
sensitive to reception problems.

When there is a change, our TV tells us a 're-tune' is needed when
switched
on. If we choose to not 're-tune' it tells us again every time it is
swiched on until we do a 're-tune'. So despite not being interested
in the
actual changes or needing the wonders of yet another crap station we
end up
being nagged into re-tuning. Can't find any way to tell the TV to
stop this
behaviour.

(Fortunately, our other systems don't give this problem and do what
we
decide without nagging or being a PITA.)

Our TV scans and finds both Durris and Angus. But refuses to give
any
choice as to which one will be used for any mux. Nor does it seem to
indicate what Mux you're using when watching a station. How typical
is
this?



Your TV is too old Jim, most modern TVs ask which region you want at
the end of an auto-tune - assuming there is a difference between the
output of the stations it has found.

Best option is manual tune it, then you will know.
Angus is 60, 53, 57*, 54, 58, 49, 31*, and 37* so almost all will have
to move.
Durris is 28, 25, 22*, 23, 26, 29, 32*, and 35* which won't need to
move.
Stations asterisked are HD.


Is there no facility to do a manual tune - or is this a feature that
someone has decided we no longer need?



--
Ian
  #25  
Old February 5th 17, 02:01 PM posted to uk.tech.digital-tv
tim...[_2_]
external usenet poster
 
Posts: 539
Default 700 MHz clearance starts March 1



"Jim Lesurf" wrote in message
...

When there is a change, our TV tells us a 're-tune' is needed when
switched
on. If we choose to not 're-tune' it tells us again every time it is
swiched on until we do a 're-tune'. So despite not being interested in the
actual changes or needing the wonders of yet another crap station we end
up
being nagged into re-tuning. Can't find any way to tell the TV to stop
this
behaviour.


TVs are meant to "learn" "no I don't want to"

yours obviously doesn't

It doesn't learn immediately as the message is sent by the broadcaster and
is repeated for a couple of weeks

but once the message is no longer being broadcast, your TV shouldn't
remember that you didn't update and continue to nag

tim



  #26  
Old February 5th 17, 02:02 PM posted to uk.tech.digital-tv
tim...[_2_]
external usenet poster
 
Posts: 539
Default 700 MHz clearance starts March 1



"Ian Jackson" wrote in message
news

Is there no facility to do a manual tune - or is this a feature that
someone has decided we no longer need?


well obviously there is, otherwise you wouldn't be able to retune when you
move house

tim



  #27  
Old February 5th 17, 02:12 PM posted to uk.tech.digital-tv
Mark Carver
external usenet poster
 
Posts: 7,594
Default 700 MHz clearance starts March 1

On 04/02/2017 21:39, Woody wrote:

How would they do that, given that Selkirk is in the same BBC
code/mux SIPSI pool as the rest of Scotland ? Any caption would
(probably) have
to be inserted within the SDI domian in the CCM centres, and would
be visible on all Scottish transmitters ?


That is exactly what we did on DSO.


Err no you didn't.

There is a caption generator on
site - don't ask me how it works - that is networked from Emley where
they can inject text, and that text only goes out on that site, not on
the relays.


Yes, it was a 1RU Softel box, that keyed in the caption, and was remote
controlled via VBI commands, as well remote controllable via telemetry,
Easy, because the baseband composite video signal was available, on the
PIE/TIE bays.

With DTT, more or less the entire transport stream for each mux is
remotely assembled, all the channels are wrapped up into the stream.
The only way to insert captions would be to decode each one, insert a
caption in the SDI domain, then re encode, very involved, and would
have a terrible effect on quality.

As said inserting would have to be way upstream at the CCM centres, and
then a special SIPSI coded pool generated for just Selkirk.

The only likely method would be an MHEG caption, triggered off by
addressing the particular SIDs etc at Selkirk. You'd need
to generate new SIDs just for Selkirk though, and that would
require a viewer re tune to enable it. Perhaps, after March 1st
when the E32 version of the mux appears, there might be an opportunity
to change the SIDs on the E50 version, to give captions on there.
Whatever, I doubt any captions will/have appeared before Mar 1st



--
Mark
Please replace invalid and invalid with gmx and net to reply.
  #28  
Old February 5th 17, 03:09 PM posted to uk.tech.digital-tv
Jim Lesurf[_2_]
external usenet poster
 
Posts: 4,228
Default 700 MHz clearance starts March 1

In article , Woody
wrote:

"Jim Lesurf" wrote in message
...



Which prompts me to wonder if people will be more likely to get
problems due to the constant 'need' presented to the user to 're-scan'
for every added vacuous shopping channel, etc. Lower near/far TX
ratios might increase the chance of RXs choosing/using the 'wrong' TX
and being more sensitive to reception problems.

When there is a change, our TV tells us a 're-tune' is needed when
switched on. If we choose to not 're-tune' it tells us again every
time it is swiched on until we do a 're-tune'. So despite not being
interested in the actual changes or needing the wonders of yet
another crap station we end up being nagged into re-tuning. Can't
find any way to tell the TV to stop this behaviour.

(Fortunately, our other systems don't give this problem and do what
we decide without nagging or being a PITA.)

Our TV scans and finds both Durris and Angus. But refuses to give any
choice as to which one will be used for any mux. Nor does it seem to
indicate what Mux you're using when watching a station. How typical
is this?



Your TV is too old Jim, most modern TVs ask which region you want at
the end of an auto-tune - assuming there is a difference between the
output of the stations it has found.


Well its only a couple of years old, and it does pop up a menu that shows
options to choose how to select a TX. But also tells me these options
aren't available when I try them.

I have wondered if this is related to the way the mux details I can recover
with a 290e show that one TX actually shows all the mux details for *both*
of them, even when it isn't transmitting one set.

Best option is manual tune it, then you will know. Angus is 60, 53, 57*,
54, 58, 49, 31*, and 37* so almost all will have to move. Durris is 28,
25, 22*, 23, 26, 29, 32*, and 35* which won't need to move. Stations
asterisked are HD.


I looked when I first got the set and couldn't find a manual tune by
channel. It may be that I missed it. However having to do that every month
or two would be a bit of a faff anyway.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

  #29  
Old February 5th 17, 03:13 PM posted to uk.tech.digital-tv
Jim Lesurf[_2_]
external usenet poster
 
Posts: 4,228
Default 700 MHz clearance starts March 1

In article , tim...

wrote:


"Ian Jackson" wrote in message
news



Is there no facility to do a manual tune - or is this a feature that
someone has decided we no longer need?


well obviously there is, otherwise you wouldn't be able to retune when
you move house


Depends what you mean. Yes, I can manually start a complete rescan. But
couldn't find any way to do this in a channel-specific manner to build up
the preferred set for a specific TX.

And if I did, I assume the TV would still start nagging again a few weeks
later when they move the deckchairs again.

So in practice we tend to ignore it for a while, then do a full rescan when
willing to let it happen.

Our recorders let us disable even being notified. Did that ages ago and
they still do whats wanted without having been rescanned in a long time.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

  #30  
Old February 5th 17, 03:17 PM posted to uk.tech.digital-tv
Robin[_8_]
external usenet poster
 
Posts: 470
Default 700 MHz clearance starts March 1

On 05/02/2017 14:12, Mark Carver wrote:
On 04/02/2017 21:39, Woody wrote:

How would they do that, given that Selkirk is in the same BBC
code/mux SIPSI pool as the rest of Scotland ? Any caption would
(probably) have
to be inserted within the SDI domian in the CCM centres, and would
be visible on all Scottish transmitters ?


That is exactly what we did on DSO.


Err no you didn't.

There is a caption generator on
site - don't ask me how it works - that is networked from Emley where
they can inject text, and that text only goes out on that site, not on
the relays.


Yes, it was a 1RU Softel box, that keyed in the caption, and was remote
controlled via VBI commands, as well remote controllable via telemetry,
Easy, because the baseband composite video signal was available, on the
PIE/TIE bays.

With DTT, more or less the entire transport stream for each mux is
remotely assembled, all the channels are wrapped up into the stream.
The only way to insert captions would be to decode each one, insert a
caption in the SDI domain, then re encode, very involved, and would
have a terrible effect on quality.

As said inserting would have to be way upstream at the CCM centres, and
then a special SIPSI coded pool generated for just Selkirk.

The only likely method would be an MHEG caption, triggered off by
addressing the particular SIDs etc at Selkirk. You'd need
to generate new SIDs just for Selkirk though, and that would
require a viewer re tune to enable it. Perhaps, after March 1st
when the E32 version of the mux appears, there might be an opportunity
to change the SIDs on the E50 version, to give captions on there.
Whatever, I doubt any captions will/have appeared before Mar 1st



As usual that's v interesting - albeit way above my head technically.
Dare I ask though if there's any other way to provide on-screen messages
given DigitalUK's briefing refers to "An information campaign to help
prepare viewers, including local advertising and on-screen messages,
will commence from mid-February 2017."


--
Robin
reply-to address is (intended to be) valid
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT. The time now is 01:19 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.SEO by vBSEO 2.4.0
Copyright 2004-2017 Digital TV Banter.
The comments are property of their posters.