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BBC News Blunder



 
 
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  #41  
Old July 31st 17, 04:01 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
Ian Jackson[_7_]
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Posts: 76
Default BBC News Blunder

In message , NY
writes
"Ian Jackson" wrote in message
...
This topic was raised this morning, in LBC Nick Ferrari spot.

He proudly said he had no idea what the speeds really meant (which I
can quite believe!), and so he invited people to phone in and tell
him how many times faster 28Mb/s was compared with 500kb/s.

I think it took six callers to get the right answer - but even he
said that at first he was going to say "17". But like many who should
know better, he kept referring to 'megabytes' instead of 'megabits
per second'.


I can understand why non-computer people refer to megabytes when they
mean megabits, because most other measures in computing are multiples
of a byte (eg a 20 kB document, 3 MB image file, a 500 GB or 1 TB hard
disk drive etc). Comms is different: speeds are usually quoted in
multiples of *bits* per second. Maybe they shouldn't be, and we should
be quoting payload speeds in multiples of bytes, excluding any
housekeeping and error-correction bits. I tend to work on a very
approximate factor of 10 when converting MB/sec and Mb/sec, allowing
for 8 bits/byte plus a bit of housekeeping.

And also speeds should as far as possible always be quoted in the same
multiple - always in kb/sec or always in Mb/sec, not a mixture of the
two. Normal engineering practice is to use the largest power that is a
multiple of 1000 such that the significant digits are in the range
1-999 (*)

so 5 Mb/s or 28 Mb/s or 157 Mb/s, but 500 kb/s rather than 0.5 Mbps

But in this case, to make comparison easier, I'd say that this is a
special case and it *should* be quoted as 0.5 Mps.


(*) Hence it is far more logical for rev counters to be calibrated 0,
1, 2, ..., 7 x 1000 rpm, as they are now, rather than the old style of
0, 10, 20, ..., 70 x 100 rpm, because the latter multiplier is not a
power of 1000. (It was also prone to people getting the speedo and rev
counter confused because both were calibrated with numbers in the same
range). And also, British English references to "seven thousand five
hundred" are more logical than US English references to "seventy-five
hundred" :-) I tend to use "hundred" notation up to 2000, and
"thousand" notation after that "fifteen hundred" but "two thousand five
hundred".


All very interesting, but it sounded like your average internet user
hadn't a clue.

As for always using the same units, it's horses for courses (miles or
furlongs).
--
Ian
  #42  
Old July 31st 17, 05:01 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
NY
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Posts: 1,214
Default BBC News Blunder

"Ian Jackson" wrote in message
...
As for always using the same units, it's horses for courses (miles or
furlongs).


All I'm saying is that maybe there is a case for a given application (eg
internet comms rates) always using the same units to make it easier for
people who aren't as conversant as us in SI prefix multipliers. Actually,
it's worse than that because k, M, G and T really imply steps of 1000x,
whereas in computing, it's common to use them to mean steps of 1024x -
except for hard disk manufacturers who use 1000 because it results in
slightly larger, more impressive numbers.

  #43  
Old July 31st 17, 05:16 PM posted to uk.tech.digital-tv
MR
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Posts: 26
Default BBC News Blunder

On Sunday, 30 July 2017 17:48:36 UTC+1, wrote:
On 30/07/2017 15:39, NY wrote:

Yes. I think GPS satellites are still in orbits about the centre of the
earth but at a lower altitude so they move relative to the earth's
surface, so a give point on the earth will see various satellites
rising, travelling across the sky and setting at different times of day..
I'm not sure how long a given satellite is above the horizon, or whether
all satellites are at the same altitude and so have the same orbit time..
I imagine that GPS satellites have orbits that are at various angles to
the equator.


Weather satellites orbit over the poles.

Bill


Some high resolution ones do, but there is global coverage from geostationary satellites as well. This produces the famous squashing up of Scotland effect which so ****ed off the Scots when they introduced those evil brown weather charts a few years' back.

MR

  #44  
Old July 31st 17, 05:20 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
Ian Jackson[_7_]
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Posts: 76
Default BBC News Blunder

In message , NY
writes
"Ian Jackson" wrote in message
...
As for always using the same units, it's horses for courses (miles or
furlongs).


All I'm saying is that maybe there is a case for a given application
(eg internet comms rates) always using the same units to make it easier
for people who aren't as conversant as us in SI prefix multipliers.
Actually, it's worse than that because k, M, G and T really imply steps
of 1000x, whereas in computing, it's common to use them to mean steps
of 1024x - except for hard disk manufacturers who use 1000 because it
results in slightly larger, more impressive numbers.


But is this really relevant to the situation where at least five people
didn't have a clue about the ratio between 500kb/s and 28Mb/s? As they
bothered to ring in, I would presume that they thought they knew
something about the subject. The closest wrong answer was 57 - but
heaven knows how the guy arrived at that conclusion.
--
Ian
  #45  
Old July 31st 17, 05:48 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
NY
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Posts: 1,214
Default BBC News Blunder

"Ian Jackson" wrote in message
...
But is this really relevant to the situation where at least five people
didn't have a clue about the ratio between 500kb/s and 28Mb/s? As they
bothered to ring in, I would presume that they thought they knew something
about the subject. The closest wrong answer was 57 - but heaven knows how
the guy arrived at that conclusion.


Given that the correct answer is 28,000,000 / 500,000 (or 28 / 0.5) = 56, I
suspect that the guy had a mental aberration about 2x28 :-)

I can understand a ratio of 500 / 28 =17, if someone neglected the
difference in multipliers and then (as is the convention for ratios) divided
the larger number by the smaller number. Wrong, but I can see the way their
mind was working.


As for the confusion between bits and bytes (b and B) - well I can
understand that too. Few people come across quantities expressed in bits,
and they may assume that b and B are equivalent and both stand for bytes.

You'd think the someone on the crew, having a technological background,
might have said "hey, that's wrong" and got the director to put the
presenters straight via the talkback earphone.

  #46  
Old July 31st 17, 07:59 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
Ian Jackson[_7_]
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Posts: 76
Default BBC News Blunder

In message , NY
writes
"Ian Jackson" wrote in message
...
But is this really relevant to the situation where at least five
people didn't have a clue about the ratio between 500kb/s and 28Mb/s?
As they bothered to ring in, I would presume that they thought they
knew something about the subject. The closest wrong answer was 57 -
but heaven knows how the guy arrived at that conclusion.


Given that the correct answer is 28,000,000 / 500,000 (or 28 / 0.5) =
56, I suspect that the guy had a mental aberration about 2x28 :-)

I can understand a ratio of 500 / 28 =17


Ah! Well spotted! [17.85714286 on my pound shop calculator.]

, if someone neglected the difference in multipliers and then (as is
the convention for ratios) divided the larger number by the smaller
number. Wrong, but I can see the way their mind was working.

As for the confusion between bits and bytes (b and B) - well I can
understand that too. Few people come across quantities expressed in
bits, and they may assume that b and B are equivalent and both stand
for bytes.


As well as not knowing the difference between the two, a lot of people
(including a certain group of radio amateurs that I listen to each
morning, who should be ashamed of themselves) also seem to use the unit
Byte as a being equal to a bit-per-second.

You'd think the someone on the crew, having a technological background,
might have said "hey, that's wrong" and got the director to put the
presenters straight via the talkback earphone.


Nick Ferrari wasn't wrong. He said (rather proudly) that he didn't
really know what 500kb/s or 28Mb/s meant. His tone was somewhat one of
'people like me don't need to bother with such trivia', and that's why
he left it the lesser mortals to phone in and fill him in with the
boring details. Unfortunately, the first five callers didn't have a clue
either.
--
Ian
  #47  
Old July 31st 17, 08:48 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
Robin[_8_]
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Posts: 458
Default BBC News Blunder

On 31/07/2017 19:59, Ian Jackson wrote:

Nick Ferrari wasn't wrong. He said (rather proudly) that he didn't
really know what 500kb/s or 28Mb/s meant. His tone was somewhat one of
'people like me don't need to bother with such trivia',


Spot on. Sadly the chattering classes don't just lack a sense of shame
that they are bad at maths, they announce the fact as if it wear a badge
of honour. Perhaps an implicit "My jobs far too important for me to
have to do sums" or "I'm far too wealthy to need to worry what 12 and a
half per cent of anything is".


--
Robin
reply-to address is (intended to be) valid
  #48  
Old July 31st 17, 09:17 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
Vir Campestris
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Posts: 404
Default BBC News Blunder

On 30/07/2017 18:38, Graham. wrote:
On Sun, 30 Jul 2017 17:49:33 +0100, "NY" wrote:

"Bill Wright" wrote in message
news
On 30/07/2017 14:33, 7 wrote:

Could you not have a satellite in a geostationary orbit above another
line
of latitude than the equator

No because Earth is a slight doughnut shape with the bulge through
the equator, and the Moon is also orbiting around the equator
which means orbits other than equator are not stationary or stable.


********


Are you saying that what 7 said is ********, or that your ******** are "a
slight doughnut shape with the bulge through the equator"? :-)


The doughnut bit is largely the correct, it's the moon orbiting the
equator that's ********, it orbits the ecliptic plane.


To coin a phrase, ********

The moon's orbit isn't quite lined up with the plane of the ecliptic.

https://en.wikipedia.org/wiki/Orbit_of_the_Moon

Andy
  #49  
Old July 31st 17, 09:50 PM posted to uk.telecom.broadband,uk.tech.digital-tv,alt.satellite.tv.europe
tony sayer
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Posts: 4,985
Default BBC News Blunder

In article , NY
scribeth thus
"Brian Gaff" wrote in message
news
I often wonder aboutsat broadband though as surely it will be painfully
slow with every packet taking significant time to go up and down again.


The big problem with satellite broadband is flow control. When you request a
web page or a download, it will indeed take a significant time for the
request to reach the server and for the returned data to start arriving.
https://en.wikipedia.org/wiki/Geostationary_orbit says that the satellite is
about 36,000 km "above the earth's equator" (I presume that's distance from
the surface, not the centre, of the earth.

So the transit time for the data will be 2 x 36,000,000 / 3x10^8 = 0.25
seconds.

Once you've started the flow of data (the initial pause) it will arrive as
quickly as it would over landlines.

But the receiving end needs to be able to control the flow of data, so it
doesn't arrive faster than can be processed. And then TCP flow-control
packets have to travel back by the same route and so will take that same
time to arrive at the sending end.

I've forgotten what the maximum amount of data is that can be sent without
acknowledgement, but I seem to remember it's only a mater of a few 1500-byte
packets, so that means that every few kB of data needs a 0.25 second pause
while the sender says "OK. Ready for some more data" and another 0.25 sec
before the sender's data arrives. This is what slows down the overall data
transfer.


And the one to many here....
--
Tony Sayer



  #50  
Old August 1st 17, 12:15 AM posted to uk.tech.digital-tv
Paul Ratcliffe
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Posts: 2,466
Default BBC News Blunder

On Mon, 31 Jul 2017 09:16:36 -0700 (PDT), MR
wrote:

This produces the famous squashing up of Scotland effect which so ****ed
off the Scots


So not all bad then.

when they introduced those evil brown weather charts a few years' back.


They'll be gone soon. Possibly to be replaced with something else evil?
Who knows.
 




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