No Teletext - please help
mike...@my-deja.com
I am unable to access Teletext on any channel - a blank 'black' screen
with nothing on it whatsoever. I have tried a reboot with no success.
Sky have been unhelpful. Please can you help ?
Sent via Deja.com http://www.deja.com/
Before you buy.
Keith Wilkinson
> I have a Hitachi Nicam TV, connected via SCART to my Panasonic Digibox.
> I am unable to access Teletext on any channel - a blank 'black' screen
> with nothing on it whatsoever. I have tried a reboot with no success.
> Sky have been unhelpful. Please can you help ?
>
I take it you mean old-style teletext on the analogue channels. I have
exactly the same problem with my large 28 inch Hitachi NICAM TV connected
via SCART1 (RGB capable) to my OnDigital STB. The only way I could get
teletext was by turning the STB off - standby was not enough. It seems
that an RGB signal comes into SCART1 and upsets the teletext display even
when SCART1 is not being watched and the RGB switching voltage is not
present. Moving to SCART2 (non RGB capable) restored teletext but then of
course I don't get RGB quality.
I eventually read the Hitachi TV manual carefully, and it actually says
in there it is recommended to UNPLUG any RGB equipment from SCART1 when
watching normal TV. This to me is a design flaw in the TV but I guess
when the TV was designed they only thought of computers and such like
being connected for RGB operation, not digital STBs that would remain
connected and switched on continuously.
BTW on very close examination I discovered the blank, black screen was
actually not completely black; there was a very very very low
illumination teletext image on it but I would never have noticed if I had
not examined the screen from an inch away with a magnifying glass.
Keith
mike...@my-deja.com
thanks for the help. I experimented last night with the SCART plug and
when the digibox is plugged into SCART2 (as you correctly anticipated)
Teletext returns.
Is there a proper solution to this problem or will I have to keep
SCART2 connected to get Teletext ? Will the advent of digital Teletext
solve the problem ?
thanks again,
Mike.
Peter Pratten
ONdigital.
In article <8118vb$ud6$1...@nnrp1.deja.com>, mike...@my-deja.com writes
> Ke...@nospam.nospam wrote:
>> In uk.tech.digital-tv wrote:
>>
>> > I have a Hitachi Nicam TV, connected via SCART to my Panasonic
>Digibox.
>> > I am unable to access Teletext on any channel - a blank 'black'
>screen
>> > with nothing on it whatsoever. I have tried a reboot with no
>success.
>> > Sky have been unhelpful. Please can you help ?
>> >
>>
the satellite analogue channels or the satellite digital channels?
>> I take it you mean old-style teletext on the analogue channels.
I suspect he means this but I thought it best to ask.
>I
>have
>> exactly the same problem with my large 28 inch Hitachi NICAM TV
>connected
>> via SCART1 (RGB capable) to my OnDigital STB.
Oh dear, I'd better ask you a similar question. Do you mean you can't
get teletext on the terrestial analogue channels or the terrestial
digital channels? Well I said 'similar' but IIRC there is only analogue
style teletext on the satellite digital channels and only digital style
on the terrestial digital channels ATM. So let's be clear which you
mean.
>The only way I could
>get
>> teletext was by turning the STB off - standby was not enough. It
>seems
>> that an RGB signal comes into SCART1 and upsets the teletext display
>even
>> when SCART1 is not being watched and the RGB switching voltage is not
>> present. Moving to SCART2 (non RGB capable) restored teletext but
>then of
>> course I don't get RGB quality.
>>
>> I eventually read the Hitachi TV manual carefully, and it actually
>says
>> in there it is recommended to UNPLUG any RGB equipment from SCART1
>when
>> watching normal TV. This to me is a design flaw in the TV but I guess
>> when the TV was designed they only thought of computers and such like
>> being connected for RGB operation, not digital STBs that would remain
>> connected and switched on continuously.
>>
Not having Hitachi I cannot comment but I sympathise with your
sentiment.
>> BTW on very close examination I discovered the blank, black screen
>was
>> actually not completely black; there was a very very very low
>> illumination teletext image on it but I would never have noticed if I
>had
>> not examined the screen from an inch away with a magnifying glass.
>>
>> Keith
>>
>Keith,
>thanks for the help. I experimented last night with the SCART plug and
>when the digibox is plugged into SCART2 (as you correctly anticipated)
>Teletext returns.
>Is there a proper solution to this problem or will I have to keep
>SCART2 connected to get Teletext ? Will the advent of digital Teletext
>solve the problem ?
>
Digital Teletext is transmitted in an entirely different way so there is
no relationship between problems with analogue and with digital.
--
Peter Pratten
Keith Wilkinson
> Oh dear, I'd better ask you a similar question. Do you mean you can't
> get teletext on the terrestial analogue channels or the terrestial
> digital channels? Well I said 'similar' but IIRC there is only analogue
> style teletext on the satellite digital channels and only digital style
> on the terrestial digital channels ATM. So let's be clear which you
> mean.
>
I did say "I take it you mean ...." before giving a possible explanation
based on that assumption. My assumption appears to have been correct;
his problem appears to be similar to mine and the same circumvention
appears to work.
As for being clear which I mean I am not quite sure why "Old style
teletext on the analogue channels" should reasonably be interpreted as
anything but the long-standing teletext services (such as CEEFAX or
Oracle) on the long-standing analogue transmissions used by such as BBC
and ITV for many years. I could refer to analogue teletext but that of
course would be incorrect as teletext uses a digital encoding of
information which I am sure someone would have pointed out.
The problem appears to be the result of a conjunction of design features
in two different pieces of equipment:
1. An OnDigital STB or Sky Digibox outputs something on the RGB SCART
pins and relies on the TV to ignore it when either told to do so or when
the RGB switching level is not raised.
2. The Hitachi TV does not completely ignore an RGB signal even though the
SCART switching signal is not present.
It would be interesting to know if TVs other than Hitachi have the same
design feature.
Keith
Keith Wilkinson
> Keith,
> thanks for the help. I experimented last night with the SCART plug and
> when the digibox is plugged into SCART2 (as you correctly anticipated)
> Teletext returns.
> Is there a proper solution to this problem or will I have to keep
> SCART2 connected to get Teletext ? Will the advent of digital Teletext
> solve the problem ?
>
I guess it is a design flaw in the Hitachi TV. If your Digibox outputs
S-video you could use that on SCART2 as something better than composite
although not RGB. Unfortunately my OnDigital STB does not have an "S"
output.
I don't know anything about digital teletext on Sky. It is now available
on OnDigital but to my mind is functionally not a patch on the old style
CEEFAX/Oracle that come with analogue transmissions. I want to be able
to press TEXT on any channel and get it without losing that channel, in
much the same way as I can press the INFO key.
Keith
mike...@my-deja.com
you say that Digital Teletext is now available with On Digital. To
obtain it are you still hooked up to SCART2 on the TV ? In other words
does Digital Teletext remove the Hitachi RGB problem ?
thanks,
Mike.
Peter Pratten
<Ke...@nospam.nospam> writes
>In uk.tech.digital-tv Peter Pratten wrote:
>
>> Oh dear, I'd better ask you a similar question. Do you mean you can't
>> get teletext on the terrestial analogue channels or the terrestial
>> digital channels? Well I said 'similar' but IIRC there is only analogue
>> style teletext on the satellite digital channels and only digital style
>> on the terrestial digital channels ATM. So let's be clear which you
>> mean.
>>
>
>I did say "I take it you mean ...." before giving a possible explanation
>based on that assumption.
I did say I suspected that was the case.
>My assumption appears to have been correct;
>his problem appears to be similar to mine and the same circumvention
>appears to work.
>
I was not sure how circumstance relating to teletext on digital
satellite and digital terrestial could be similar.
>As for being clear which I mean I am not quite sure why "Old style
>teletext on the analogue channels" should reasonably be interpreted as
>anything but the long-standing teletext services (such as CEEFAX or
>Oracle) on the long-standing analogue transmissions used by such as BBC
>and ITV for many years. I could refer to analogue teletext but that of
>course would be incorrect as teletext uses a digital encoding of
>information which I am sure someone would have pointed out.
>
I avoided the use of the term 'analogue teletext' for that very reason
and used 'analogue style teletext' to refer to the 'old style' we are
used to.
The term 'teletext', unless qualified, can be misunderstood because it
is both a generic term and the name of the company that replaces Oracle
as providing the service on the independant channels (ng readers are not
known for being careful in distinguishing between upper case and lower
case initials). It is also used for the replacement service on the
digital terrestial service but, ATM, only on specific channels.
My problem is that I cannot see how the ONdigital STB could in any way
affect such teletext as the latter is generated inside the TV. In the
case of the Mike's digital satellite box I understand that such 'old
style' does exist so the circumstances do not seem similar - that is
unless I had misunderstood something, therefore I asked both you and
Mike for clarification.
>The problem appears to be the result of a conjunction of design features
>in two different pieces of equipment:
>
>1. An OnDigital STB or Sky Digibox outputs something on the RGB SCART
>pins and relies on the TV to ignore it when either told to do so or when
>the RGB switching level is not raised.
>
Are you saying that a signal on the SCART affects normal analogue
channels tuned within the TV or the teletext on them?
>2. The Hitachi TV does not completely ignore an RGB signal even though the
>SCART switching signal is not present.
>
In this case I can only say 'Ughh!'
>It would be interesting to know if TVs other than Hitachi have the same
>design feature.
>
>Keith
>
--
Peter Pratten
Keith Wilkinson
> I was not sure how circumstance relating to teletext on digital
> satellite and digital terrestial could be similar.
>
Well if the poster is referring to inability to view the long-established
teletext services carried on analogue transmissions when the Digibox is
plugged in then it appears to me to be a TV or SCART interface problem and has
nothing to do with digital transmissions at all.
On the other hand if he is referring to viewing old-style telelext which is
transmitted by SKY along with the BBC1 etc on a digital channel in a similar
fashion to how teletext information is piggybacked on an analogue transmission
it might be a different matter. I assume, and please correct me, that in this
latter case the decoding of old-style teletext is done as usual by the TV not
the Digibox and therefore the TV needs a composite signal containing the usual
old-style teletext information. An RGB signal into the TV has already been
decoded and so the TV cannot extract any teletext information and won't even
try.
If this is the case I would hope SKY would make it clear to its customers that
they should use a composite not an RGB signal if they wish to receive
old-style teletext transmitted by them on its digital channels. Not being a
SKY subscriber I have no experience of how things need to be set up for SKY
viewing.
> The term 'teletext', unless qualified, can be misunderstood...
Which is precisely why I qualified it.
> Are you saying that a signal on the SCART affects normal analogue
> channels tuned within the TV or the teletext on them?
I don't say it affect the channels themselves but it certainly seems to affect
the way in which the old-style analogue transmission teletext is displayed -
that is with illumination so low as to be almost invisible. The fact that
Hitachi recommend that RGB equipment be unplugged from SCART1 when not being
used indicates they suspect some adverse effect. A TV design flaw IMHO.
Keith
Keith Wilkinson
> Keith,
> you say that Digital Teletext is now available with On Digital. To
> obtain it are you still hooked up to SCART2 on the TV ? In other words
> does Digital Teletext remove the Hitachi RGB problem ?
>
> thanks,
> Mike.
>
Digital teletext on OnDigital is completely different from old-style
telext (CEEFAX/Oracle) as carried on the analogue transmissions. It is
carried on its own digital channels (9 for teletext and 10 for BBC text)
and is decoded by the STB not the TV. It is as yet very rudimentary in
both content and function. The BBC variety looked very good in the test
transmissions as it was possible to see both teletext and picture in a
window simultaneously but the channel 9 variety is to me as yet a dead
loss. I am sure both will improve greatly before long.
Keith
Sandy
>An RGB signal into the TV has already been
>decoded and so the TV cannot extract any teletext information and won't even
>try.
So why can I read it on C&W digital using RGB input? Sky, C5, QVC and
one or two others - but not BBC/ITV channels.
--
Sandy
delete nospam. to e-mail
Keith Wilkinson
> >An RGB signal into the TV has already been
> >decoded and so the TV cannot extract any teletext information and won't even
> >try.
>
If what I said was incorrect then say so but if you are going to quote me then
do it properly and include the "I assume, and please correct me..." that went
before your snippet.
>
> So why can I read it on C&W digital using RGB input? Sky, C5, QVC and
> one or two others - but not BBC/ITV channels.
> --
> Sandy
I don't know. Can you tell us ? Is this perhaps a cunning plot by Sky to
discourage us watching teletext on free to air channels ?
Keith
Keith Wilkinson
Pemberton wrote:
> The scart delivers RBG _and_ composite to the telly, which uses the
> latter to produce a synchronised raster. The teletext circuitry extracts
> the vertical interval data from the composite signal if there's any
> there and displays it as normal when you press "text".
>
> However, some tellies don't switch to teletext when the video input is
> forced to RGB by the scart lead - many, like yours, do.
>
> As to which channels carry FLOF (full level one facilities - ie
> "analogue") teletext - that's up to the cable operators, or more
> probably up to whoever supplies them with their signals.
That's interesting to know. Thanks for the explanation.
Keith
gu...@dialogue.co.uk
> "Keith Wilkinson" <Ke...@nospam.nospam> wrote:
>
> >An RGB signal into the TV has already been
> >decoded and so the TV cannot extract any teletext information and won't even
> >try.
>
> So why can I read it on C&W digital using RGB input? Sky, C5, QVC and
> one or two others - but not BBC/ITV channels.
> --
> Sandy
>
> delete nospam. to e-mail
you are not, when pressing TV then text you are actually swicthing your digibox
output to composite. Its easily noticeable as the color then to fade slighly and
look rather dull.
G.
Sandy
>> So why can I read it on C&W digital using RGB input? Sky, C5, QVC and
>> one or two others - but not BBC/ITV channels.
>> --
>you are not, when pressing TV then text you are actually swicthing your digibox
>output to composite. Its easily noticeable as the color then to fade slighly and
>look rather dull.
Eh? I'm not touching the cable box. I just press the text button on
the TV remote and up pops teletext. I doubt very much that the box
can detect what I am doing and convert its output.