Don Pearce wrote:
On Thu, 13 Aug 2009 11:05:32 +0100, "Dave Plowman (News)"
wrote:

In article 4a89dc62.791606671@localhost,
Don Pearce wrote:
And as regards Sky - do you know how it gets its BBC radio feeds? That
could well be via NICAM. Just because the end link to the home is
showing a good data rate doesn't mean it's the same in the entire
chain...
From what I can see examining the Sky transmissions, I don't believe
they receive a NICAM feed.
I'm not sure the original NICAM is still in use generally for BBC
distribution either. It's a very old system.

It still is - NICAM 3 is the standard. This is 14:10, just the same as
used for TV sound. Shame really as NICAM 2 (14:11) came out better in
listening panel tests. Certainly for a distribution system there was
no excuse for compromising sound quality. I guess they wanted
compatibility for purchasing cheapness.

Nicam-2 (14:11) was rejected in favour of Nicam-3 (14:10) because its
only advantage in listening tests was to reduce programme-modulated
noise to (what was considered at the time to be) an unnecessarily low
level, at the expense of bit-rate. Nicam-3's lower bit-rate enabled six
15 kHz channels (or 3 stereo pairs) to be transmitted down a 2 Mbit/sec
E3 leased line.

Chapter and verse he

http://www.bbc.co.uk/rd/pubs/reports/1978-26.pdf


--
Richard Lamont http://www.lamont.me.uk/

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In article ,
Richard Lamont wrote:
Chapter and verse he

http://www.bbc.co.uk/rd/pubs/reports/1978-26.pdf

Interesting, thanks.

--
*Why don't sheep shrink when it rains?

Dave Plowman London SW
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