Audio Precision System One Dual Domani Measuirement Systems

[Mark Zenier]

In article <PZmdnUB6c6JMCLDSnZ2dnUVZ_oudnZ2d@giganews.com>,
Arny Krueger <arnyk@cocmast.net> wrote:

The Hoover Dam in Nevada and the Grand Coulee dam in Washington state were
also built at about the same time. The Grand Coulee Dam provided massive
amounts of electric power to the Hanford plutonium refining facility.

Hanford consisted of running Uranium through carbon moderated water
cooled reactors, and then disolving the slugs in acid and chemically
seperating out the plutonium. (Buzzword: Purex). Not all that much
power demand, but tankloads of really radioactive crap that's still
there, 65 years later.

It was aluminum smelters. (The output of which got turned into heavy
bombers during WWII). There were, postwar, seven in Washington,
two in Oregon and one in western Montana, producing about a third of
the country's Aluminum. With the increasing population's power demand
soaking up the excess and raising power prices, and new competition
from Russia and Iceland, most, or all of them, have shut down now.

Eventually, in the last incarnation of the plutonium production facilites,
the N reactor, the cooling was used to generate electrical power.

(A new use for the power is Internet server farms. Microsoft has a big
one in Euphrata, near Grand Coulee, and Google has a one down in Oregon,
at The Dalles or Hood River).

Mark Zenier mzenier@eskimo.com
Googleproofaddress(account:mzenier provider:eskimo domain:com)

 

[David Looser]

"J. P. Gilliver (John)" <G6JPG@soft255.demon.co.uk> wrote in message
news:+eM$aIX8faMPFwga@soft255.demon.co.uk...

In message <9pacbsFqtlU1@mid.individual.net>, David Looser
david.looser@btinternet.com> writes:
[]
Well it might, but in practice there don't seem to have been many problems
caused by not harmonising spectrum use with the the continent. To be
honest
I think the government made the right decision, the limited VHF spectrum
available in Bands 1 & 3 would only just have been enough for one extra
625-line TV channel.
[]
? - one on band I and at least one on band III, surely? I lived in (West)
Germany in the 1960s and '70s, and I'm sure we could get at least two
channels on band III (yes, I know B and G channels are narrower, but not
that much).
--

In the UK Band 1 was divided into 5 channels which, with care, could just
about support one national TV network. (a few low-power fill-in transmitters
for 405-line BBC1 had to operate in Band 3)

With 8MHz channels that would reduce to 3 which I suggest is not enough for
one national network.

Of course if you are only looking for local coverage you could run several
networks in the available spectrum. But the argument was that VHF gave
better national coverage than UHF. If that is the aim then, I suggest, you'd
need both Bands 1 and 3 to give truly national coverage of just one network.
Its probable that it would be possible to add a second network that only
covered the main population centres, as Analogue Channel 5 did on UHF.

David.

 

[Geoffrey S. Mendelson]

David Looser wrote:

Of course if you are only looking for local coverage you could run several
networks in the available spectrum. But the argument was that VHF gave
better national coverage than UHF. If that is the aim then, I suggest, you'd
need both Bands 1 and 3 to give truly national coverage of just one network.
Its probable that it would be possible to add a second network that only
covered the main population centres, as Analogue Channel 5 did on UHF.

I don't know how well UK sets worked in the 1960's, but US TV sets were
not capable of receiving adjcent channels at one time, so they were not
used. For example, channel 2 was used in New York City, while the nearest
channel 3 station was in Philadelphia, 90 miles away and too far to be
received without a large antenna.

I think the next one up was 5 in NYC and 6 in Philly.

When the US started UHF TV in the mid 1960's (all 1965 models had to
have VHF/UHF tuners), they spaced the channels far apart, Philadelphia
for example had three, 17,29 and 48.

Geoff.

--
Geoffrey S. Mendelson, N3OWJ/4X1GM
My high blood pressure medicine reduces my midichlorian count. :-(

 

[Ian Jackson]

In message <slrnjj4j7v.ap9.gsm@cable.mendelson.com>, Geoffrey S.
Mendelson <gsm@mendelson.com> writes

David Looser wrote:

Of course if you are only looking for local coverage you could run several
networks in the available spectrum. But the argument was that VHF gave
better national coverage than UHF. If that is the aim then, I suggest, you'd
need both Bands 1 and 3 to give truly national coverage of just one network.
Its probable that it would be possible to add a second network that only
covered the main population centres, as Analogue Channel 5 did on UHF.

I don't know how well UK sets worked in the 1960's, but US TV sets were
not capable of receiving adjcent channels at one time, so they were not
used. For example, channel 2 was used in New York City, while the nearest
channel 3 station was in Philadelphia, 90 miles away and too far to be
received without a large antenna.

I think the next one up was 5 in NYC and 6 in Philly.

Generally, UK (and even European) TV sets had a hard time with adjacent

channels. Like the USA, the off-air broadcast channels were arranged so
that, within the normal service area, there would never be an adjacent
channel which was anything like as strong as the channel(s) intended for
that area.

The same was true of cable systems. As TV sets were incapable of
operating with adjacent channels, they carried only alternate channels.

However, things changed with the advent of cable set-top boxes. These
were specifically designed to be capable of receiving a level(ish)
spectrum of maybe 30+ channels. The tuned channel was converted to a
single output channel in Band 1 (selected to be a vacant off-air channel
in the area where the STB was to be used). Essentially, all the adjacent
channel filtering was done on output channel, so the TV set was
presented with only a single channel, thereby eliminating any problems
with poor adjacent channel selectivity.

Early STBs covered only non-off-air channels, eg 'midband' (between
Bands 2 and 3) and 'superband' (above Band 3 to around 300MHz). As a
result, large cable TV systems would carry alternate channels in Bands 1
and 3 (so that they could be received directly by the TV set), and
adjacent channels elsewhere (which could normally only be received via
the STB).

Later on, when multi-channel cable TV was recognised as 'the way to go'
by the TV set manufacturers, TV sets themselves started being equipped
with wideband tuners - typically providing virtually continuous coverage
from 50 to 300MHz and beyond, plus the UHF TV broadcast band. At the
same time, TV set adjacent channel selectivity was improved, as they had
to be capable of receiving the adjacent cable channels.

In the 1980s, SAW filters became widely available for use in domestic TV
sets, and these virtually eliminated the problems of interference from
adjacent channels. Of course, eventually, cable TV set-top boxes also
developed further, providing not only continuous wideband coverage of
from 50 to 870MHz, but they also became descramblers/decoders for pay-TV
services.

When the US started UHF TV in the mid 1960's (all 1965 models had to
have VHF/UHF tuners), they spaced the channels far apart, Philadelphia
for example had three, 17,29 and 48.

IIRC, at first, UHF was not very popular in the USA. Tuners were pretty

rudimentary - consisting of virtually nothing except a triode variable
frequency oscillator and a crystal diode mixer (techniques essentially
borrowed from WW2 radar technology), and this fed the input of the
existing VHF tuner. UHF transmitter powers were low, and as receiver
sensitivity was not much better than a crystal set, coverage was
minimal, so virtually no one bothered much with UHF TV. As a result, TV
sets continued to be manufactured fitted with only the traditional
12-channel lowband/highband VHF tuner.

Eventually, because of total congestion in the VHF TV bands, I believe
the FCC stepped in, and more or less forced TV manufactures to fit the
additional UHF tuner. I believe understand that they did this rather
indirectly - not by requiring TV manufacturers to fit UHF tuners per se,
but instead by making it illegal for them to ship TV sets across a state
border if they did not have a UHF tuner.
--
Ian

 

[Terry Casey]

In article <XyWb9YCiEWMPFwHY@g3ohx.demon.co.uk>,
ianREMOVETHISjackson@g3ohx.demon.co.uk says...

In message <MPG.299b4fb86cac4d2398970d@news.eternal-september.org>,
Terry Casey <k.type@example.invalid> writes
In article <4f2fec88$0$6884$e4fe514c@news2.news.xs4all.nl>,
iimeeltje@hotmail.com.invalid says...


Other western European countries[1] used system B in a 7MHz channel
width and system G in an 8MHz channel at UHF.

To use the same channels we would have needed to devise a system X with
a truncated vestigial side-band to fit our 6MHz sound-vision spacing
into 7MHz - in reality, I don't think it would have fitted!

Of course, both the British and the Irish could have simply adopted the
European systems B and G (5.5MHz sound-vision - plus the horrendous
group delay pre-correction curve).

As the UHF bands had been engineered by international agreement for 8MHz
channels to accommodate all European 625 line systems (with the vision
frequency being common to all of them), it made sense to make better use
of the bandwidth available - in fact, as we were starting from scratch,
I've often wondered why we didn't adopt the eastern European OIRT
standard with its 6MHz vision bandwidth.

As for group delay, I suppose it made sense to pre-correct the
transmission to suit the average receiver group delay response. Were the
system I parameters, without group delay correction, determined in the
belief that UK manufacturers were so much better at designing IF strips
than their continental counterparts? ;-)

Group delay was something I never thought about - until a rude awakening
doing early experimental work on Teletext - but the introduction of SAW
filters resolved the problem ...

If I remember correctly, the only
difference between systems B and G is the 7 vs 8 MHz channel spacing.
Even the VSBs are the same (0.75MHz).

Yes, but don't forget the Belgian system H with 1.25MHz vsb ...

In practice, if we had decided to carry on using VHF for 625 line
broadcasting, I think we would have harmonised with the Irish 8MHz
channel plan - not least because of the proximity of NI transmitters to
those in the republic.

Again, IIRC, the RoI VHF 625-line channels were the same frequencies as
the 'lettered' 625-line channels already used on many VHF cable TV
systems.

Chicken and egg situation? RTE was broadcasting using VHF 625-line
channels at least two years before BBC2 came along. I think you meant:
many VHF cable TV systems used the 'lettered' 625-line channels already
used by RTE ...

Continental systems, of course, used the CCIR broadcast channels, as
well as filling up the gaps in between ...

--

Terry

 

[Terry Casey]

In article <525e05ab07dave@davenoise.co.uk>, dave@davenoise.co.uk
says...

In article <buZ2G1VrVaMPFwno@soft255.demon.co.uk>,
J. P. Gilliver (John) <G6JPG@soft255.demon.co.uk> wrote:
UK wiring regulations require earth (ground) wires to be sheathed in
green and yellow sleeving where it is exposed.

I have often been puzzled by this requirement. What is the reason - just
identification of the earth wire, or something else?

It's just belt and braces - slightly less chance of a short if wires get
trapped by careless assembly.

It's also been changed twice!

Originally, earth wires were bare, then the requirement to cover them
with green sleeving was brought in.

Finally, the sleeving was changed from green to green/yellow ..

--

Terry

 

[Terry Casey]

In article <+eM$aIX8faMPFwga@soft255.demon.co.uk>,
G6JPG@soft255.demon.co.uk says...

In message <9pacbsFqtlU1@mid.individual.net>, David Looser
david.looser@btinternet.com> writes:
[]
Well it might, but in practice there don't seem to have been many problems
caused by not harmonising spectrum use with the the continent. To be honest
I think the government made the right decision, the limited VHF spectrum
available in Bands 1 & 3 would only just have been enough for one extra
625-line TV channel.
[]
? - one on band I and at least one on band III, surely? I lived in
(West) Germany in the 1960s and '70s, and I'm sure we could get at least
two channels on band III (yes, I know B and G channels are narrower, but
not that much).

Were both channels available nationwide or just in densely populated
areas?

Or is German topography more amenable to providing large area coverage
with fewer transmitters?

(I'm thinking here of the German plains that we were told for many years
provided ease of access for Soviet tanks ...)

--

Terry

 

[Clive]

In message <5w1wNIHt+lMPFwzc@g3ohx.demon.co.uk>, Ian Jackson
<ianREMOVETHISjackson@g3ohx.demon.co.uk> writes

IIRC, at first, UHF was not very popular in the USA. Tuners were pretty
rudimentary - consisting of virtually nothing except a triode variable
frequency oscillator and a crystal diode mixer (techniques essentially
borrowed from WW2 radar technology),
When I have a book about faults in American NTSC sets and was surprised

to see just how cut down they were. Instead of "I" subcarrier being
1.5MHz it was reduced in the sets to 1.0 MHz because that was the same
as the "Q" subcarrier and it made the sets cheaper to produce, with of
course the lower colour accuracy, but that came second to price.
--
Clive

 

[Terry Casey]

In article <5w1wNIHt+lMPFwzc@g3ohx.demon.co.uk>,
ianREMOVETHISjackson@g3ohx.demon.co.uk says...

In message <slrnjj4j7v.ap9.gsm@cable.mendelson.com>, Geoffrey S.
Mendelson <gsm@mendelson.com> writes
David Looser wrote:

Of course if you are only looking for local coverage you could run several
networks in the available spectrum. But the argument was that VHF gave
better national coverage than UHF. If that is the aim then, I suggest, you'd
need both Bands 1 and 3 to give truly national coverage of just one network.
Its probable that it would be possible to add a second network that only
covered the main population centres, as Analogue Channel 5 did on UHF.

I don't know how well UK sets worked in the 1960's, but US TV sets were
not capable of receiving adjcent channels at one time, so they were not
used. For example, channel 2 was used in New York City, while the nearest
channel 3 station was in Philadelphia, 90 miles away and too far to be
received without a large antenna.

I think the next one up was 5 in NYC and 6 in Philly.

Generally, UK (and even European) TV sets had a hard time with adjacent
channels. Like the USA, the off-air broadcast channels were arranged so
that, within the normal service area, there would never be an adjacent
channel which was anything like as strong as the channel(s) intended for
that area.

The same was true of cable systems. As TV sets were incapable of
operating with adjacent channels, they carried only alternate channels.

<SNIP>

The UK UHF band plan specifically avoided the use of channels n, n + 5
and n + 9 in any transmitter group (n + 5 = n + IF; n + 9 = n + 2*IF) to
prevent interference.

I was quite surprised not to find any problems with a cable system I
started work on in 1969 which used 22 adjacent VHF channels (45 -
228MHz). As the system provided financial information only, there were
no sound carriers.

All the receivers used were modified domestic receivers using the ITT/KB
VC100 chassis. This chassis was effectively the old dual standard
chassis that had gone through at least five iterations that I can
remember - VC1, VC2, VC3, VC51, VC52 - in the previous four or five
years, with all the 405-line bits left out. Consequently it was really
quite an old design.

The GPO (which was just starting to transform itself into BT) were
responsible for the RF generation and trunk distribution and had chosen
a non-standard 8.3MHz channel spacing to ensure that the local
oscillator never clashed with a vision channel. This was possibly
inherited from the ILEA schools CCTV system they'd run because the
tuning errors they'd allowed for were a joke as our receiver tuning
always had to be spot-on because of the high frequency component of the
video - think CEEFAX in vision but with 48 character[1] lines.

Despite the adjacent channel traps in the receivers still being aligned
for 8MHz spacing(!) we never encountered any problems.

All later (broadcast) CATV and SMATV systems I've encountered, though,
have always used alternate channels, as described by Ian, for channels
intended for direct reception by a domestic receiver (i.e.: without
first being received by an STB).

[1] The worst characters in the special set used in these pre-decimal
days were 10 and 11 (for tenpence and elevenpence). Of these, ten was
the worst, producing a 10101 pixel sequence for most of its height -
tuning really had to be spot on for this!

--

Terry

 

[Mike Tomlinson]

In article <MPG.299c7f0c70c46016989710@news.eternal-september.org>,
Terry Casey <k.type@example.invalid> writes

Finally, the sleeving was changed from green to green/yellow ..

IIRC, it was to make it easier for colour-blind people to identify.

There's also been another change: the cores in T&E (=romex) used to be
red and black for phase and neutral, now it's been harmonised with
Europe to brown and blue.

Three-phase wiring has been harmonised from red, blue and yellow for the
phases and black neutral to brown, black, black and blue neutral. Yeah,
I know...

--
(\__/)
(='.'=)
(")_(")

 

[Mortimer]

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:IOXK0rJlCoMPFwnx@jasper.org.uk...

Three-phase wiring has been harmonised from red, blue and yellow for the
phases and black neutral to brown, black, black and blue neutral. Yeah,
I know...

You mean that two of the phases are the *same* colour? Surely not: how do
you know whether it's safe to connect two wires if they could be on
different phases? And if you connect brown, black and black to a three phase
motor and get the two blacks the wrong way round it will run backwards.

 

[Ian Jackson]

In message <MPG.299c7c76417bea5098970e@news.eternal-september.org>,
Terry Casey <k.type@example.invalid> writes

In article <XyWb9YCiEWMPFwHY@g3ohx.demon.co.uk>,
ianREMOVETHISjackson@g3ohx.demon.co.uk says...

In message <MPG.299b4fb86cac4d2398970d@news.eternal-september.org>,
Terry Casey <k.type@example.invalid> writes
In article <4f2fec88$0$6884$e4fe514c@news2.news.xs4all.nl>,
iimeeltje@hotmail.com.invalid says...


Other western European countries[1] used system B in a 7MHz channel
width and system G in an 8MHz channel at UHF.

To use the same channels we would have needed to devise a system X with
a truncated vestigial side-band to fit our 6MHz sound-vision spacing
into 7MHz - in reality, I don't think it would have fitted!

Of course, both the British and the Irish could have simply adopted the
European systems B and G (5.5MHz sound-vision - plus the horrendous
group delay pre-correction curve).

As the UHF bands had been engineered by international agreement for 8MHz
channels to accommodate all European 625 line systems (with the vision
frequency being common to all of them), it made sense to make better use
of the bandwidth available - in fact, as we were starting from scratch,
I've often wondered why we didn't adopt the eastern European OIRT
standard with its 6MHz vision bandwidth.

As for group delay, I suppose it made sense to pre-correct the
transmission to suit the average receiver group delay response. Were the
system I parameters, without group delay correction, determined in the
belief that UK manufacturers were so much better at designing IF strips
than their continental counterparts? ;-)

With System B , I think it's the closer proximity of the TV adjacent

sound traps that create the horrendous group delay curve. In System I,
they are 0.5MHz further away, and that seems to make all the difference.

Group delay was something I never thought about - until a rude awakening
doing early experimental work on Teletext - but the introduction of SAW
filters resolved the problem ...

So you've never had the ecstatic pleasure of tuning up the group delay
pre-distortion circuit in a System B/G modulator? ;o)))))

Of course, Norway realised the SAW filters for TV set IFs could be made
with a flat group delay response (rather than slavishly mimicking the
traditional L/C horrendous "-90, +140 microsecond" curve). For reasons
unknown to me, they decided to change the pre-distortion curve of their
transmitters to something like "flat to 4MHz, and -100us at 5MHz".
Heaven knows what your average Norwegian TV set made of this!

If I remember correctly, the only
difference between systems B and G is the 7 vs 8 MHz channel spacing.
Even the VSBs are the same (0.75MHz).


Yes, but don't forget the Belgian system H with 1.25MHz vsb ...

I've never actually come across it. Is it actually used? I guess it's

simply a relaxation of the unnecessarily-tight VSB roll-off of System G.
However, as the TV set IFs will all be B/G, they will hardly know the
difference.

In practice, if we had decided to carry on using VHF for 625 line
broadcasting, I think we would have harmonised with the Irish 8MHz
channel plan - not least because of the proximity of NI transmitters to
those in the republic.

Again, IIRC, the RoI VHF 625-line channels were the same frequencies as
the 'lettered' 625-line channels already used on many VHF cable TV
systems.


Chicken and egg situation? RTE was broadcasting using VHF 625-line
channels at least two years before BBC2 came along. I think you meant:
many VHF cable TV systems used the 'lettered' 625-line channels already
used by RTE ...

Ah! You could well be right. I only recently became aware that the Irish

launched their 625-line broadcasts in 1962, and of course, at the time,
the BBC were still only making experimental transmissions (albeit at
UHF). It's therefore unlikely that UK cable systems had any 625-line
programmes to put out until 1964 - and that would only have been BBC2.
It therefore makes sense that they adopted the Irish VHF TV frequency
plan, instead of vice versa!

Continental systems, of course, used the CCIR broadcast channels, as
well as filling up the gaps in between ...

--
Ian

 

[J G Miller]

On Wed, 08 Feb 2012 12:54:56 +0000, Terry Casey wrote:

Were both channels available nationwide or just in densely
populated areas?

Are you talking about channels or stations?

In the analog days of television in Bundesrepblik Germany, the three public networks
ARD Das Erste, ZDF, and die Dritten Fernsehprogramme (regional TV stations)
were available nationwide but as is the case in all countries (except Netherlands
and Vlaanderen), transmitter coverage was not 100%.

In the late 1980s, two commercial networks were allowed to start terrestrial
broadcasts -- RTL and Sat Eins, but these were low power and only available
in major urban markets.

With the switch off of analog TV, all TV transmissions in Germany are now
on UHF channels. In Western Europe, only Danmark and Letzebuerg have
transmitters with DVB-t on VHF Band III.

<http://www.ukwtv.DE/sender-tabelle/>

If you want to see which stations are available in the nation's capital
and surrounding region (Berlin-Brandenburg) then take a look at
the tables at

<http://www.mabb.de/digitale-welt/dvb-t/programme.html>

Note that in order to provide a good quality SD picture with rock solid
reception, the modulation is 16-QAM 8k FFT, and only four TV stations
per multiplex. Meanwhile SDN crams 12 video streams into 64-QAM 8k FFT
with reduced FEC because commercial dross trash and profits are more important
than picture quality and reception stability in a free-market light
touch regulatory broadcast framework.

 

[Terry Casey]

In article <jgtuep$vgr$5@dont-email.me>, miller@yoyRG says...

On Wed, 08 Feb 2012 12:54:56 +0000, Terry Casey wrote:

Were both channels available nationwide or just in densely
populated areas?

Are you talking about channels or stations?

Stations (sorry - copied what the OP wrote ...)

In the analog days of television in Bundesrepblik Germany, the three public networks
ARD Das Erste, ZDF, and die Dritten Fernsehprogramme (regional TV stations)
were available nationwide but as is the case in all countries (except Netherlands
and Vlaanderen), transmitter coverage was not 100%.

The OP was referring to VHF transmissions in the 60s and 70s - are you
sure you are not wandering of into UHF territory here? That would make a
considerable difference to coverage ...

--

Terry

 

[Ron]

On 08/02/2012 14:18, Mortimer wrote:

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:IOXK0rJlCoMPFwnx@jasper.org.uk...
Three-phase wiring has been harmonised from red, blue and yellow for the
phases and black neutral to brown, black, black and blue neutral. Yeah,
I know...

You mean that two of the phases are the *same* colour? Surely not: how
do you know whether it's safe to connect two wires if they could be on
different phases? And if you connect brown, black and black to a three
phase motor and get the two blacks the wrong way round it will run
backwards.

It's brown, black. grey, blue. Still stupid and difficult for those with
colour blindness or working in low light.

Ron

 

[David Looser]

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:IOXK0rJlCoMPFwnx@jasper.org.uk...

In article <MPG.299c7f0c70c46016989710@news.eternal-september.org>,
Terry Casey <k.type@example.invalid> writes

Finally, the sleeving was changed from green to green/yellow ..

IIRC, it was to make it easier for colour-blind people to identify.

There's also been another change: the cores in T&E (=romex) used to be
red and black for phase and neutral, now it's been harmonised with
Europe to brown and blue.

Three-phase wiring has been harmonised from red, blue and yellow for the
phases and black neutral to brown, black, black and blue neutral. Yeah,
I know...

BS7671 says that the colours are brown, black and grey, with blue for
neutral.

David.

 

[Mike Tomlinson]

In article <woOdnWrZAqC7Ga_SnZ2dnUVZ7q2dnZ2d@brightview.co.uk>, Mortimer
<me@privacy.net> writes

You mean that two of the phases are the *same* colour?

Yes.

Surely not

Unbelievable but true. Foisted on us by the Eurocrats in Brussels.

: how do
you know whether it's safe to connect two wires if they could be on
different phases?

you don't

And if you connect brown, black and black to a three phase
motor and get the two blacks the wrong way round it will run backwards.

precisely.

I can see the benefit in changing from red+black to brown+blue in T&E as
those are the same colours used in flex, but to go from our previous
widely understood red/yellow/blue + black to the new scheme is less
convincing.

The idea, I think, was to continue the concept that the brown wire is
phase and blue neutral for consistency, but to use two black wires for
the second and third phases... words fail me.

See this:

http://jasper.org.uk/ingleses.jpg

this was an installation where a distribution board built in Britain was
shipped to a remote location in Europe. The Spanish electricians needed
a crib sheet to match up the colours correctly

--
(\__/)
(='.'=)
(")_(")

 

[Mike Tomlinson]

In article <9pfgg1F8frU1@mid.individual.net>, David Looser
<david.looser@btinternet.com> writes

BS7671 says that the colours are brown, black and grey, with blue for
neutral.

Must have changed, then, 'cos I have seen several installations with
brown/black/black and blue. Also see the pic I posted earlier - look at
the Spanish names for the harmonised colours.

--
(\__/)
(='.'=)
(")_(")

 

[David Looser]

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:FeMJAlKI8oMPFwnN@jasper.org.uk...

In article <9pfgg1F8frU1@mid.individual.net>, David Looser
david.looser@btinternet.com> writes

BS7671 says that the colours are brown, black and grey, with blue for
neutral.

Must have changed, then, 'cos I have seen several installations with
brown/black/black and blue.

BS7671 permits the use of other colours as long as the ends of the wires are
clearly labelled "L1", "L2" etc. I guess the installers simply didn't have
any grey cable.

Also see the pic I posted earlier - look at
the Spanish names for the harmonised colours.

L1 is brown, yet your picture has "negro" against L1, so I'm not sure that

we can place any confidence in its veracity.

David.

 

[Mike Tomlinson]

In article <9pfisvFrb6U1@mid.individual.net>, David Looser
<david.looser@btinternet.com> writes

BS7671 permits the use of other colours as long as the ends of the wires are
clearly labelled "L1", "L2" etc. I guess the installers simply didn't have
any grey cable.

No, this is an armoured underground cable with cores in the colours
stated.

L1 is brown, yet your picture has "negro" against L1, so I'm not sure that
we can place any confidence in its veracity.

<shrug> I took the photo, and have seen the installation several times.
Here's another photo, since you seem to have trouble handling the truth:

http://jasper.org.uk/disboard.jpg

Let's not talk about the croc clips, shall we?

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