BBC Teletext

[spof]

On the BBC Teletext they have £ and then the figure.

Yes, I get that on my Blackberry and I've seen it on Teletext and I think it's due to how the extended versions of ASCII are applied as well as where the information is coming from.

Glen

[Jean McGurn]

Silly thought coming up 

I wonder if the operator who types up the teletext is using a 'foreign' computer so that when he/she types in the £ sign it comes up as  £

By 'foreign' I of course mean set up for a language other than English. Maybe they have forgotten to change the language.

As I said a silly thought 

Jean

[Stumped!]

I wonder if the operator who types up the teletext is using a 'foreign' computer so that when he/she types in the £ sign it comes up as  £

Perhaps they've outsourced the website to a distant country?   

Peter

[DudleyWinchurch]

Now I am really going to show my age ... and the memory is going so may not be entirely accurate but I thnk what's happening is ...

Back in the old days when computers were extremely small by today's standards, all information had to be coded in bytes.  A byte is a block of 8 bits, binary units that could stand for 0 or 1. 

So, if you only have 8, you can only represent numbers 0-255 (1+2+4+8+etc.), so ASCII was only able to encode (I think) 255 characters as 0, or maybe 00 was the marker to say that you were at the end of the file.

When computers got bigger they usually added an extra byte (or more) to the start of this so you map to much bigger character sets, and embed codes to change the styles or swap into graphics but, if you enter the code in a wordprocessor, where it's coded in 16 bits or more then the first part may get translated to something else when it's played back through something that only works in 8 bits, like Teletext.

[Jean McGurn]

Now you have completely lost me.  Unless of course those computers used 8 inch floppy discs like the first computer I ever used.   

Jean

[DudleyWinchurch]

Floppies      I said I was showing my age! 

Home computers used cassette recorders when I started.  No direct access to data at all.  And the big computers used rooms of reel-to-reels.  This wasn't just backup either.  Internal storage was purely temporary and was wiped when you turned them off.

8" were a modern luxury and then they went down to 5 1/2" before someone decided that we were taking the "floppy" thing too literally and needed to put them in the hard case versions.

But I digress ...

The problem was that with a restricted character set, there was a very basic set and some extra numbers that were used for different things in different countries.  When they stored them in larger units the higher end could be packed with zeroes for the standard set, mapping to exactly the same number (like in dates, 1/7/1882 is the same as 01/07/1882), the other numbers had/have a code in front to denote which set they were/are representing at the time.

I presume the  is the one used to denote the extra British character set and appears when anything belonging specifically to that set is used in contexts that can't use it properly.  The same number in the American char. set was mapped to to the dollar sign and for a long time it was very common when using a British keyboard, to type pound and have it appear as dollar because the keyboard is independent of the software so just transferring numbers. The teletype printer       had to have the right software (or more likely hardware) too, to know that you meant pound.

By the way, different "natural" languages have different numbers of graphemes (characters) in their alphabets so, apart from the order they appear in, in words, there is a lot more than just mapping to a different shape, to getting the same commands to come out right at the top level.

[spof]

I presume the  is the one used to denote the extra British character set and appears when anything belonging specifically to that set is used in contexts that can't use it properly.  The same number in the American char. set was mapped to to the dollar sign and for a long time it was very common when using a British keyboard, to type pound and have it appear as dollar because the keyboard is independent of the software so just transferring numbers. The teletype printer       had to have the right software (or more likely hardware) too, to know that you meant pound.

Which is why Americans refer to # as the pound sign as, if I recall correctly, their keyboard layout has the # above the number 3 key and British computing ruled the world at the time.

This is an example of the theory behind the Y2K "bug" when computers could only store dates as DD/MM/YY and you were quoting life insurance, say, for someone born 5/11/04...is it from a parent of a child who is 3 or 103?

I expect the Teletext news stories are taken directly from the system they use for managing their websites which means it is sending it in a language more complex than the Teletext system can understand.