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FoxyMX
25-10-2005, 04:44 PM
Does anyone else have problems with their TV capture card not displaying teletext subtitles properly?

My Leadtek TV2000XP Expert quite often will not display captions/subtitles at all and at other times the captions are rather messy, with wrongly displayed or dropped letters making words and sentences really fun to try and read. Quite often the TV One news captions won't display but they are there on the main TV when I check.

Would this be a signal problem or just something that the capture card might struggle with? It is plugged into an external TV aerial.

Would be interested to know whether others have problems as well.

bob_doe_nz
25-10-2005, 07:31 PM
I'd say its a signal issue. Currently my leadtek winfast TV tuner is displaying A-OK.
The tele in the lounge however does not always display the proper channel and needs to wait for the next refresh to get back to normal.

Speedy Gonzales
25-10-2005, 07:36 PM
Yup, I would say it'll be a signal prob.

Usually TV 1 is bad for teletext, as its a weak signal/channel.

2 and 3 are better.

FoxyMX
25-10-2005, 07:40 PM
Haha, TV1 is behaving nicely right now but TV2 is shocking. It's dropping half of the letters and is almost impossible to follow. The program before that was the same on TV2 but I couldn't get the TV1 news captions at all again tonight.

I will have to investigate the signal somehow, by the looks of it.

bob_doe_nz
25-10-2005, 07:42 PM
You havent recently had bad weather around your area have you po*ky?

FoxyMX
25-10-2005, 08:23 PM
How recent is recent, Taffer? We had snow last month, remember? :eek:

'Twas bad before that but I wasn't looking at the captioning so much then so I'm not sure if it has got worse or not.

Billy T
25-10-2005, 08:48 PM
Go to page 199 Sis, that is the reception test page and should display uniform columns of characters. If it doesn't, your TV signal is not up to scratch. Try it on different channels (1, 2, or 3) as you will usually find that one is OK and that confirms that it is a signal problem.

IIRC there is another test page as well, but I can't remember which one it is at present. Tweak'e may be able to remind me.

Bro Billy :)

FoxyMX
25-10-2005, 09:28 PM
Thanks Billy, I didn't know about that page. :thumbs:

Looks like it is a reception problem (http://imagef1.x10hosting.com/files/teletext01.jpg). :(

That is on TV2 ten minutes ago. TV1 isn't quite as bad but TV3 is currently not showing those symbols at all, only the title at the top of the page and the "Home", "World", etc at the bottom. All are perfectly clear though, unlike the other two channels which are similar to the pic.

Is this a sign of a deteriorated TV aerial? It is around 10 years old, I think, and was professionally installed, not a home handyman job (for once :p).


Edit: I ought to point out that the original screenie is a lot more colourful than what the pic shows. The conversion to .jpg has dulled all the colours significantly, in case that matters at all.

FoxyMX
26-10-2005, 06:47 AM
D'oh!! I just remembered something. :blush:

Previously there were two televisions running off this aerial and I had to get a three-way splitter in order to hook up the computer's TV card. I was warned that it could possibly cause signal deterioration to the TVs so maybe that is the reason the Teletext is rather poor. I wasn't able to try it before adding the splitter so I have no idea if it was better previously.

Looks like it may be a good idea to put it back how it was and see whether it runs better without the splitter. :rolleyes:

Billy T
26-10-2005, 07:11 AM
Well, I found the other page(s), they are 299 & 399 but they are the same as 199. IIRC this is called the "clock cracker"

If it is that, it is made up of characters that require the most digital data to produce (the highest hex value?) which makes it the most difficult page to transmit and reproduce. It is used for testing the receiver and reception, and if the clock cracker page is ok, everything else should be.

The problem could be weak signal or distorted signal (the latter may not be obvious on picture material) so you might want to try a direct feed to your computer to see if it is OK. I find that if I am watching TV via a VCR, the teletext gets mangled and I have to turn the VCR off and use direct signal to view teletext properly.

It could be your TV card of course, and probably is if you have the same teletext problem on all three channels, but I'd try a direct feed as a test, then try cleaning up the signal if that works OK.

Cheers

Billy 8-{) ;)

FoxyMX
26-10-2005, 07:50 AM
Thanks Billy, I'll do some experiments later on.

Not sure exactly what you mean by "direct feed" though. The TV card on the computer doesn't go via a video or anything, just plugged straight into the three-way splitter up in the ceiling at the other end. Perhaps you mean remove the splitter and try it? I'll send The Boss up to change things around when he gets home tonight. :p

Oh, and what does "cleaning up the signal" mean? How does one do that? :blush:

Billy T
26-10-2005, 08:37 AM
Not sure exactly what you mean by "direct feed" though.
A direct connection between antenna and input to your TV card, no splitters or other devices in between. Even a splitter with nothing connected to the other outlets can mangle teletext, though you usually find that one channel will work OK. It depends on what channels your TV1/2/3 are on. If they are all on high-band (small aerial, but not as small as Sky terrestrial) then they may all suffer. If one is on low-band (big aerial with long elements) then this test usually works.


Oh, and what does "cleaning up the signal" mean? How does one do that? :blush:
In two words, "spending money" or perhaps getting the Boss more deeply involved if he is a practical type.

It means checking the aerial connections and cables for rust, other corrosion & water damage etc. If your TV pictures are perfect on TV1/2/3 then there is probably nothing wrong, but even a slight ghost can interfere with Teletext. And I mean perfect too, I've had people tell me their picture is perfect and when you get there it is the biggest load of snow and ghosting you have ever seen, they just didn't know any better!

Some "signal bending" conditions can cause problems with colour or teletext on an otherwise perfect signal but that is rare. I remember a case where the picture went monochrome on one channel every evening when hubby arrived home. Parking his car in the carport was enough to kill the colour on just one channel. It was a really weird signal propogation issue, but easy to resolve once the cause was found.

God, I'm rambling and reminiscing, both at the same time! :eek:

I'm outa here. :xmouth:


Cheers

Billy 8-{)

FoxyMX
04-03-2007, 03:38 PM
In two words, "spending money" or perhaps getting the Boss more deeply involved if he is a practical type.

It means checking the aerial connections and cables for rust, other corrosion & water damage etc. If your TV pictures are perfect on TV1/2/3 then there is probably nothing wrong, but even a slight ghost can interfere with Teletext. And I mean perfect too, I've had people tell me their picture is perfect and when you get there it is the biggest load of snow and ghosting you have ever seen, they just didn't know any better!


Hey Billy, guess what? Despite The Boss going up the ladder several times over the past 18 months (gosh, doesn't time fly? :eek:) the captioning and reception of the TVs got worse and worse until only half the captions were displaying properly on a bad day. The rest were either invisible or so severely mangled that it was impossible to read them.

After the cables from socket to TV were changed with no improvement I suggested several times that an aerial person be called in since The Boss could see nothing wrong with anything anywhere. The trouble is that a lot of tradesmen absolutely loathe having others doing work for them unless it is impossible for them to do the work themselves so he kept stalling, as he tends to do. Being a bit of a "Target" junkie I'm full of sympathy for this attitude, especially since the memory of a so-called 'tradesman' putting his entire foot and leg through our ceiling whilst in the attic has not yet faded. Aerial people need to go into the attic so you can kind of understand his reluctance to call one in.

Anyways, the captions, or lack of them, were really bad one day last week whilst trying to watch something I was really interested in, causing me to run from the room in tears of frustration. In hindsight I should have tried this months ago because The Boss was on the phone first thing the next morning arranging an aerial man to come around, at long last. :thumbs:

Well, blow me down, the day before the appointment Murphy came knocking. Yes, you guessed it, the picture and captions were absolutely perfect, the best we have ever seen. This caused me to jump up and down with glee as there was now no doubt as to what the cause was - the day previous was one of the hottest and driest this summer and had obviously dried out the connections up on the aerial. To prove this I sent The Boss out to spray a bit of water in the direction of the aerial and sure enough, we got the bad picture back again almost immediately.

You would think that the aerial man would have been pleased to have his customers make the diagnosis for him but all we got was a telling off for wetting the thing. :blush:

Ah well, he did his magic up there and even though he couldn't do much about the slight ghosting due to the neighbour's house which had mushroomed after the aerial was first installed, the picture and captions are the best they have been for years so I'm happy. :cool:

Don't you just love a happy ending, even if it is nearly 18 months later? :p

Billy T
04-03-2007, 07:57 PM
Don't you just love a happy ending, even if it is nearly 18 months later? :p
Love it! Nothing like finally getting around to fixing something 18 months later. I've got a few odd jobs on the go for Mrs T that have been waiting, oh, 19 or 20 years. :blush:

In fact, I was today putting handles on a sliding door (that we had custom made back in the mid 80's) as a preliminary to finally mounting it in place.

Our TV reception and Teletext is ok though. :D

Cheers

Billy 8-{) :thumbs:

R2x1
04-03-2007, 10:43 PM
Billy T - Does Mrs T appreciate the trouble you have been to in order to keep her 20 year old door "as new"?

Billy T
05-03-2007, 08:02 AM
Billy T - Does Mrs T appreciate the trouble you have been to in order to keep her 20 year old door "as new"?
*cough* :blush: I kept it hidden under a tarpaulin in the garage, where it was largely out of sight and out of mind. However, any protests were slightly muted when I produced the receipt showing that we originally paid in excess of $1000 to have the door custom made (plus the cost of the sliding track). That was a fair wallop of cash in those days, when we were newly married and saddled with a large mortgage.

But, that's not all! Even that pales into insignificance when you take into account the $1200+ we just paid for four bevelled-edge glass panes, each with a stained glass native flower insert, that she had custom made after I yielded to subtle pressure (do it or else) and agreed to install the door before a planned social event next month.

In real terms of today's money, that all adds up to well in excess of $3000 for a door that will almost never be closed, but will only ever be seen in its true glory when it is closed. The rest of the time it will be seen only briefly when coming up a flight of stairs (thank god she didn't insist that it slide away inside the wall!).

Then there's my time away from my work sorting the installation etc.

Love is not only blind, it is stupid as well, but she's a powerful woman Mrs T.

SWMBOOPOD

Cheers

Billy 8-{) :xmouth: