NICAM and BBC technical history info

[Jim Lesurf]

I have recently been trying to collate info on the PCM systems the BBC have
used for sound radio distribution. One aspect that was more elusive was the
'NICAM-3' for radio distribution to the FM TXs (as distinct from NICAM for
analogue TV broadcasts).

I found a copy of "NICAM 3 A companded PCM system for the transmission of
high quality sound programmes" by Cairne, English, and Robinson of the BBC
Designs Dept on the mb21 site. This gives useful info on the framing, etc,
but the only clue to where this was published is that the pages have the
numbers 274 to 277. Anyone know where this comes from?

Also, the BBC website has various white papers and R&D publications. But -
so far as I've see so far - not the monographs or Design Dept documents.
Anyone know if these are available, either on the BBC site or some other
site? I've found the 'Eng Inf' site for other documents.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

[tony sayer]

In article <521b48e...@audiomisc.co.uk>, Jim Lesurf
<no...@audiomisc.co.uk> scribeth thus

>I have recently been trying to collate info on the PCM systems the BBC have
>used for sound radio distribution. One aspect that was more elusive was the
>'NICAM-3' for radio distribution to the FM TXs (as distinct from NICAM for
>analogue TV broadcasts).
>
>I found a copy of "NICAM 3 A companded PCM system for the transmission of
>high quality sound programmes" by Cairne, English, and Robinson of the BBC
>Designs Dept on the mb21 site. This gives useful info on the framing, etc,
>but the only clue to where this was published is that the pages have the
>numbers 274 to 277. Anyone know where this comes from?
>
>Also, the BBC website has various white papers and R&D publications. But -
>so far as I've see so far - not the monographs or Design Dept documents.
>Anyone know if these are available, either on the BBC site or some other
>site? I've found the 'Eng Inf' site for other documents.
>
>Slainte,
>
>Jim
>

Might try posting that on the Tx-list on mb21 Jim, several ex BBC /IBA
transmission hang out there...
--
Tony Sayer

[Andy Wade]

On 01/10/2011 10:39, Jim Lesurf wrote:

> Also, the BBC website has various white papers and R&D publications. But -
> so far as I've see so far - not the monographs or Design Dept documents.
> Anyone know if these are available, either on the BBC site or some other
> site? I've found the 'Eng Inf' site for other documents.

Some of the monographs are here:
http://www.bbc.co.uk/rd/library/bbc_monographs/

and /BBC Engineering/ journal which succeeded the monograph series is here:
http://www.bbc.co.uk/rd/library/bbc_engineering/

--
Andy

[Jim Lesurf]

In article <9esaa2...@mid.individual.net>, Andy Wade

Thanks, yes, I'd found the engineering before my posting, and the
monographs afterwards. I'd initially missed the monographs as the link
looked to me like just being to one issue. Only when I got curious did I
discover this had a sidebar for all the others!

The difficulty is these often focus on R and D before end-design, or give a
general report of what goes in service. But not give details of the in
service kit or dates/locations of install/update.

I've also now found a fair number of the Designs Dept documents on the
bbceng.info website. The snag is that these are mainly listed by code, and
I haven't yet managed to 'crack the code' and find out what docs may refer
to, say, the 13-channel system the BBC started to install in 1972.

Finding out details seems to vary a lot depending on the topic.

The general details of 'nicam' are relatively easy, since a lot has been
written about this from the 'TV' point of view. Alas, that often omits
explaining the differences between that and the 'nicam-3' used for radio
distribution.

Finding out about the 13-channel PCM is harder because there are a series
of 'R&D' documents detailing the work done when develeloping this, showing
various part-work and different choices/ideas/options. So the difficulty is
determining what actually went into service. So far the best I've found is
an article by Reg Williamson in 'Hi Fi News' in 1974! Which, alas, is a bit
vague.

FWIW I've also noticed some confusion in comparing items about this over
the years. I suspect that some writers have included a parity bit in how
many 'bits per sample' they quote.

Finding out details of install dates, etc, also seems difficult. I've found
mentions of the first install of the 13-channel system to Wrotham. But
little else.

I guess some of this will have been reported in WW of old. Alas, my copies
and lists have a gap in the 1970s at present. So maybe a trip to the uni
library is on the cards! :-)

[Jim Lesurf]

In article <Em+SnUNJ...@bancom.co.uk>, tony sayer
<to...@bancom.co.uk>
wrote:

> In article <521b48e...@audiomisc.co.uk>, Jim Lesurf
> <no...@audiomisc.co.uk> scribeth thus
> >I have recently been trying to collate info on the PCM systems the BBC
> >have used for sound radio distribution. One aspect that was more
> >elusive was the 'NICAM-3' for radio distribution to the FM TXs (as
> >distinct from NICAM for analogue TV broadcasts).

> Might try posting that on the Tx-list on mb21 Jim, several ex BBC /IBA
> transmission hang out there...

Well, I did try sending an email about something else to mb21 some time
ago, but didn't get any response. However perhaps I should try again.

FWIW I've sent an email to Martin at bbceng.info, so I'm hoping he will
contact me and be able to help.

It was a surprise to me to have confirmed that the BBC *still* use nicam
(-3) for fm distribution. Although I can see the "if tain't broke, don't
fix it" argument. Indeed, since many audiophiles love FM and regard it as
'analogue' I guess they confirm this choice by the BBC. :-)

However it set me wondering about the history of using 'digital' methods
for radio distribution, and I started to realise that people seem to have
forgotten the details of the early systems and how early they came into
use, etc.

[charles]

In article <521c49a...@audiomisc.co.uk>,

Jim Lesurf <no...@audiomisc.co.uk> wrote:
> In article <Em+SnUNJ...@bancom.co.uk>, tony sayer
> <to...@bancom.co.uk>
> wrote:
> > In article <521b48e...@audiomisc.co.uk>, Jim Lesurf
> > <no...@audiomisc.co.uk> scribeth thus
> > >I have recently been trying to collate info on the PCM systems the BBC
> > >have used for sound radio distribution. One aspect that was more
> > >elusive was the 'NICAM-3' for radio distribution to the FM TXs (as
> > >distinct from NICAM for analogue TV broadcasts).

> > Might try posting that on the Tx-list on mb21 Jim, several ex BBC /IBA
> > transmission hang out there...

> Well, I did try sending an email about something else to mb21 some time
> ago, but didn't get any response. However perhaps I should try again.

> FWIW I've sent an email to Martin at bbceng.info, so I'm hoping he will
> contact me and be able to help.

Martin retired a few months ago, so you may not get a reply.

--
From KT24

Using a RISC OS computer running v5.16

[Jim Lesurf]

On 03 Oct, no...@audiomisc.co.uk wrote:


> Finding out about the 13-channel PCM is harder because there are a
> series of 'R&D' documents detailing the work done when develeloping
> this, showing various part-work and different choices/ideas/options.

> Finding out details of install dates, etc, also seems difficult. I've
> found mentions of the first install of the 13-channel system to Wrotham.
> But little else.

Now made some headway by finding info in the 'comms' section of
bbceng.info. Excellent site! :-)

[tony sayer]

In article <521c49a...@audiomisc.co.uk>, Jim Lesurf

<no...@audiomisc.co.uk> scribeth thus
>In article <Em+SnUNJ...@bancom.co.uk>, tony sayer
><to...@bancom.co.uk>
>wrote:
>> In article <521b48e...@audiomisc.co.uk>, Jim Lesurf
>> <no...@audiomisc.co.uk> scribeth thus
>> >I have recently been trying to collate info on the PCM systems the BBC
>> >have used for sound radio distribution. One aspect that was more
>> >elusive was the 'NICAM-3' for radio distribution to the FM TXs (as
>> >distinct from NICAM for analogue TV broadcasts).
>
>> Might try posting that on the Tx-list on mb21 Jim, several ex BBC /IBA
>> transmission hang out there...
>
>Well, I did try sending an email about something else to mb21 some time
>ago, but didn't get any response. However perhaps I should try again.
>
>FWIW I've sent an email to Martin at bbceng.info, so I'm hoping he will
>contact me and be able to help.
>
>It was a surprise to me to have confirmed that the BBC *still* use nicam
>(-3) for fm distribution. Although I can see the "if tain't broke, don't
>fix it" argument. Indeed, since many audiophiles love FM and regard it as
>'analogue' I guess they confirm this choice by the BBC. :-)

IIRC its running at something like 728 K/Bits ... So should be good....

>
>However it set me wondering about the history of using 'digital' methods
>for radio distribution, and I started to realise that people seem to have
>forgotten the details of the early systems and how early they came into
>use, etc.
>
>Slainte,
>
>Jim
>

That is on a site somewhere .. can't remember where at the moment 'tho.!
--
Tony Sayer

[davidr...@postmaster.co.uk]

Thanks for that link. OT, but the articles on satellite broadcasting
and digital television written in 1980 are well worth a read...
http://downloads.bbc.co.uk/rd/pubs/archive/pdffiles/engineering/bbc_engineering_115.pdf
...some of it was well used commercially, but it's amazing how much of
it proved to be commercially wrong/hopeless.

Cheers,
David.

[Jim Lesurf]

In article <521c5b7a...@charleshope.demon.co.uk>, charles

If not, is there someone else who might be happy to help?

The difficulty I have is partly the likelyhood that not all the info is on
the web, and partly that it is generally spread across various 'divisions',
etc. Can be confusing for an innocent ex-academic. :-)

For example, I just found the EDI document 10155 on the site, and that has
some useful info on the orginal 13-channel system. But I keep finding these
things by a sort of semi-random-walk process as I don't (yet) know enough
about who (and which division, etc) did what, when. It all makes sense
*once* I find the info. But it can be a bit like looking up a word when you
have no idea how it is spelt, or even in what language! :-)

In that case I initially though R&D would have the info. Then thought
Designs was more likely, but found it under Comms... as an EDI document.

For those experienced in the ways of the BBC of old, such byways will be
familiar. But for outsiders like myself it can be a bit of a maze.

FWIW I know one or two people at the BBC who are happy to give me some
'current' help. But they don't know about the details of decades ago, and
are busy with their day jobs.

Another point is that the bbceng.info site mentions a DVD of the items. But
I haven't yet found any details, or if this is still available. Alas, some
of the scans in the pdfs are quite difficult for me to read as my eyesight
is poor. So I'm hoping those on a DVD will be more comprehensive and more
(visually) detailed! Or does the DVD only cover eng inf?

[Jim Lesurf]

In article <r0E5D2Ch...@bancom.co.uk>, tony sayer
<to...@bancom.co.uk>
wrote:

> In article <521c49a...@audiomisc.co.uk>, Jim Lesurf
> <no...@audiomisc.co.uk> scribeth thus

> >

> >It was a surprise to me to have confirmed that the BBC *still* use
> >nicam (-3) for fm distribution. Although I can see the "if tain't
> >broke, don't fix it" argument. Indeed, since many audiophiles love FM
> >and regard it as 'analogue' I guess they confirm this choice by the
> >BBC. :-)

> IIRC its running at something like 728 K/Bits ... So should be good....

Yes, in essence it is still 14bit companded down into 10bits scaled in 1 ms
chunks.

[Mark Carver]

Jim Lesurf wrote:
> In article <521c5b7a...@charleshope.demon.co.uk>, charles
> <cha...@charleshope.demon.co.uk> wrote:
>> In article <521c49a...@audiomisc.co.uk>, Jim Lesurf
>> <no...@audiomisc.co.uk> wrote:
>
>
>>> FWIW I've sent an email to Martin at bbceng.info, so I'm hoping he
>>> will contact me and be able to help.
>
>> Martin retired a few months ago, so you may not get a reply.

I think there's a confusion regarding Martins !

Charles I suspect was referring to Martyn Culling, who used to work for the
BBC Engineering Infomation Dept. Jim is referring to Martin Ellen, who is the
curator of the BBC Eng Info website (run by Martin, not the Beeb) ?


--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

[charles]

In article <9euchd...@mid.individual.net>, Mark Carver

<mark....@invalid.invalid> wrote:
> Jim Lesurf wrote:
> > In article <521c5b7a...@charleshope.demon.co.uk>, charles
> > <cha...@charleshope.demon.co.uk> wrote:
> >> In article <521c49a...@audiomisc.co.uk>, Jim Lesurf
> >> <no...@audiomisc.co.uk> wrote:
> >
> >
> >>> FWIW I've sent an email to Martin at bbceng.info, so I'm hoping he
> >>> will contact me and be able to help.
> >
> >> Martin retired a few months ago, so you may not get a reply.

> I think there's a confusion regarding Martins !

> Charles I suspect was referring to Martyn Culling, who used to work for
> the BBC Engineering Infomation Dept. Jim is referring to Martin Ellen,
> who is the curator of the BBC Eng Info website (run by Martin, not the
> Beeb) ?

you are correct.

[Jim Lesurf]

In article <521c8251...@charleshope.demon.co.uk>, charles

> you are correct.

Yes. Pleased to add that I've now had a reply from Martin Ellen.