I don't know how long this has been there, but DigitalUK has set up a test page with "clock cracker" style white blocks that is viewable on BBC1/2, ITV1 and Channel 4/S4C by going to page 284 on the analogue teletext service.
This is the first time I've come across this and the first I've heard about it, so forgive me if you already knew about it.
Very interesting, so give it a try if you're yet to switch over!
Well my aerial passed the test, yet on hot sunny days I regularly lose the whole BBC Mux. I know little about Teletext decoding, but how good a test is this?
I would argue its based on the fact that Teletext/Ceefax is painfully fickle as to whether you get a good enough signal in order to display all the characters. You only need a slight drop in signal strength or slight change in atmospheric conditions to throw the ability to receive a full Teletext service out of the window so to speak. Therefore if you have missing white dots when receiving page 284 it could imply your aerial is not good enough for use in a digital world.
It's interesting that they're not carrying out this test on Five, as some areas receive Five from a different transmitter to the main four channels. So perhaps they're assuming people would be more likely to get their Freeview signal from the transmitter that gives them the main four channels, and not everyone can get an analogue signal from Five so perhaps there wouldn't be a lot of point doing it on Five in that case.
It's interesting that they're not carrying out this test on Five, as some areas receive Five from a different transmitter to the main four channels. So perhaps they're assuming people would be more likely to get their Freeview signal from the transmitter that gives them the main four channels, and not everyone can get an analogue signal from Five so perhaps there wouldn't be a lot of point doing it on Five in that case.
The test is for DTT reception after DSO. It's not relevant as a test for present DTT reception, as the power levels are much lower than they will be post DSO.
There's no point carrying the test on C5, because many C5 analogue transmitters are not co-located with BBC/ITV/4, and/or employ lower power.
That's interesting. Our Freeview differs in the living room and the kitchen. There are a string of electricity pylons a few hundred yards from our house, directly in the line of sight between the aerial and the Winter Hill transmitter. Our analogue signal is very good (there's no grain etc.) but we have severe ghosting from the pylons which make the channels (esp. BBC 1) practically unwatchable. Now, we have an IDTV in the living room which receives Freeview perfectly. I'm yet to see the signal break up on that TV. However, in the kitchen at the rear of the house, the Freeview signal is dodgy even though it is coming from the same aerial. As soon as it rains, many of the channels break up and disappear which proves very annoying. I've just done that test and it shows perfect results on every channel. Do you think we should get an aerial installer in now to try to fix the problems, or should we wait for DSO? Do you think the power at the transmitter will be increased enough to overcome the problems on the kitchen TV?
I'd stay put, and see what happens post DSO. It could be that your kitchen TV has an inferior tuner, and is being overloaded with the much stronger analogue signals from Winter Hill. This is a known problem, the tuner is unable to decode the weaker DTT signals properly, because of analogue 'shouting' next door. Once DSO is complete, that should not be an issue
That's interesting. Our Freeview differs in the living room and the kitchen. There are a string of electricity pylons a few hundred yards from our house, directly in the line of sight between the aerial and the Winter Hill transmitter. Our analogue signal is very good (there's no grain etc.) but we have severe ghosting from the pylons which make the channels (esp. BBC 1) practically unwatchable. Now, we have an IDTV in the living room which receives Freeview perfectly. I'm yet to see the signal break up on that TV. However, in the kitchen at the rear of the house, the Freeview signal is dodgy even though it is coming from the same aerial. As soon as it rains, many of the channels break up and disappear which proves very annoying. I've just done that test and it shows perfect results on every channel. Do you think we should get an aerial installer in now to try to fix the problems, or should we wait for DSO? Do you think the power at the transmitter will be increased enough to overcome the problems on the kitchen TV?
Thanks in advance for any help.
Its very wierd as every TV in my house has a freeview box and is on the same aerial but down stairs its badder than upstairs.
As for the text thing I passed but I cant get Multiplex A and 2
I'm not sure how valid this test is given that one of the big issues with teletext reception is multipath (signals bouncing off something else and reaching the aerial delayed with respect to the main signal, the cause of ghosting) which is supposed to not be an issue with DTT?