In article 4a89dc62.791606671@localhost, Don Pearce
wrote:
On Thu, 13 Aug 2009 10:04:29 +0100, "Dave Plowman (News)"
wrote:


Absolutely, and I realise that the upper frequency limit for NICAM is
just about the same as that for FM. Maybe I'm just writing from the
position of someone who listened to Wrotham, which always had a good
feed. But FM has always been problematic, particularly in a city where
multipath pretty well destroys the signal.

It was certainly the case that whereever I lived in London the main limits
on FM performance were due to a mix of multipath, ignition interference,
taxis, and pirates. So being near Wrotham didn't fix any of that.

Up in the 'frozen north' though, having good distribution to the TX has
probably made a major difference to the end-result. But reception is still
audibly affected by things like interference.

Slainte,

Jim

--
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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
To e-mail, change noise into sound.

"Gordon MacPherson" wrote in message
...
Hi,
We will be moving from Oxford to Dorset (BH20 5BB). At present I use a
Denon tuner. I am concerned about getting good FM reception in this part
of Dorset and am wondering about the relative qualities of sound derived
from FM and from our digital TV (we will be using Sky). Both will feed
into a decent amp and speakers. I mainly listen to classical music.

Thanks,

Gordon

Many thanks - very interesting and prolem solved!

Gordon

In article 4a86dc10.725989343@localhost, Don Pearce
scribeth thus
On Wed, 12 Aug 2009 16:04:44 +0100, "Gordon MacPherson"
wrote:

Hi,
We will be moving from Oxford to Dorset (BH20 5BB). At present I use a Denon
tuner. I am concerned about getting good FM reception in this part of Dorset
and am wondering about the relative qualities of sound derived from FM and
from our digital TV (we will be using Sky). Both will feed into a decent amp
and speakers. I mainly listen to classical music.

Thanks,

Gordon


Sky is your best bet. UK FM transmitters are fed by NICAM digital
signals, so you end up with the worst of both worlds. DAB has pretty
much unacceptable bit rates. Freeview is not at all bad, but none is
as good as satellite currently.

d


Try a good FM aerial and tuner if you like what you hear then fine

Else go satellite which even the bit rates aren't what they could be its
a good alternative.

Avoid terrestrial DAB its a waste of space;!..
--
Tony Sayer