* Posts by jphb

57 publicly visible posts • joined 17 Sep 2009


Kepler may be dead but its data keeps on giving, thanks to AI: Two alien worlds found in archives


Re: Hi Vladimir. The Board is Yours for Now to Lead with LOVE*


Things that make you go .hm... Has a piece of the internet just sunk into the ocean? It appears so


Not so isolated

The article is wrong in stating that the Heard and Macdonald Islands are the most isiolated place in the world. That honour belongs to Bouvet Island, a Norwegian (yes!) dependency roughly half way between South Africa and Antarctica. It shares the honour of a dormant DNS domain (.bv). I remember lecturing a class of computer science students on the SMTP protocol and mentioning casually the existence of unused domains. When I got back to the office, via the staff bar, there was an email for me from Bill.Gates@microsoft.bv !

Big contenders in the broadband chart this week, but who will be #1? Well, not Britain


In the 1990's a company called Telewest (remember them) dug up all the pavements in town and generally created a mess that everybody moaned about. They installed twin coaxial links back to kerbside cabinets with separate wires for a POTS service. Rates seemed reasonable and the cable TV was attractive (no unsightly aerials) so I signed up, domestic Internet connections were for the future. Still with them, although it's now Virgin Media, the Internet connection now gives a rock solid 220 Mb although I understand it'll hit the buffers at 350 Mb.

If 25+ year old technology can do this, what have BT been playing at for the last quarter century?

Facebook claims a third more users in the US than people who exist


Re: What Is The Point of Facebook ?

I don't think Facebook actually makes money, they just relieve other people of it.

15 'could it be aliens?' fast radio bursts observed in one night


Re: CQ Contest

They'll have changed the scoring system by the time your reply reaches them

Linux lads lambast sorry state of Skype service


Linux and Skype

Well I've just used the Skype "echo test" serivce and it worked perfectly with my Linux Skype client. IThe robot assured me that my Skype client was configured correctly. Am I missing something?

Boffins: The universe is DOOMED and there's nothing to be done


And why did I feel a sudden wish to type "inifinite improbability drive" into E-Bay?

Exploding 'laptop batt' IN SPAAACE! Speeding lithium spaffed by nova


Re: So, how much lithium then ?

That's really 2000 Exakilograms or 2 trillion billion kilograms or 2 octillion milligrams.

What exactly is wrong with saying 2 X 10E+24 grams


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A new world - new puzzles

Fascinating animation. Quite unlike Luna - no maria, no rays from carters, one "rille" like structure to the left of the two bright spots. I get the impression that the other bright spots and patches are predominantly on one side of the planet. Does this suggest a single event was responsible for all the birght spots and patches? What's the size distribution of the craters, I got an impression that there are more medium-large ones than I'd expect - but am I deluding myself?

Saturn's rings, radio waves ... poetry? At home with Scotland's Mr Physics


Re: Whilst in the area....

If you turn left on exiting Waverley Station you will be walking WEST along Princes Street, not East.

And whilst you're checking this out on Google Street View switch 3D photo-realistic buildings on and,

if you're PC's up to it, enjoy.



Re: Star Trek is already around it.

Odd that the Klingons, Romulans, Ferengi etc., etc., don't seem to need deflector dishes on their ships - ah, got it, Einstein wasn't a Klingon or Romulan etc., so presumably their physics is different.

Robot deputy blasts possibly explosive Mexican beans with CANNON in 'controlled explosion'


Re: Ticking?

And, of course, atom bombs are always fitted with a flashing count-down timer - who for?

Boffins snap first pics of hot white dwarf nova bursting out of its shell

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Hurrah for amateurs

Amongst all the tedious academic name checking that appears in the part of Nature article not behind the paywall I see no mention of Koichi Itagaki, the amateur discoverer of this nova. Surely he (well I assume it's a he) deserves more recognition - at least his voice might be heard more clearly when asking the local authority to be more careful with siting the street lights.

Protesters stop ground breaking on world's largest telescope


Re: Wow Ten times further

"Wow. Currently we can see some 13 billion light years so the visible universe will now ten times bigger."

So we'll be able to see objects who's light started out 130 billion years ago,

that's 116.2 billion years before the creation of the universe - should be interesting.

Google wants to KILL apps with the 'Physical Web'


So, if I understand this correctly, every gadget in the neighbourhood will be continuously broadcasting URI information on the assumption that people walking or driving past will be continuously looking at a display of all the broadcasting gadgets in the neighbourhood (rather than looking where they're going). What does "continuously" mean in this context? How often do devices broadcast? How much energy does all this consume? How much radio frequency spectrum? What happens when device broadcasts clash with each other - will there be a race to higher power and more frequent broadcasts causing further clashes etc., etc.,

Sometimes I think advertising should be made a criminal offence.

Boffins attempt to prove the universe is just a hologram


Re: Interesting times

This was discussed in the August issue of Scientific American. I have a niggling feeling that in a universe with 4 extended spatial dimensions, attractive forces exerted by a "point" like object would fall off in accordance with an inverse cube law rather than the inverse square law in our universe. This would mean that bound structures such as electrons orbiting atomic nuclei and planets orbiting stars are not possible. Not sure about atomic nuclei and the strong and weak forces though.

Unfortunately at this time in the morning my maths isn't up to exploring this further.

Weather forecast: WiFi storms make meteorologists look mad


Re: wifi is a nuisance

The reason it shows as a line is, I presume, that the rotating aerial of the weather radar only picks up the WiFi signal when the weather radar's aerial is pointing at the nuisance. The picture gives a clear indication of the bearing from the radar to the WiFi, the width of the "line" is indicative of the width of the weather radar's aerial beam. Given the low power of the Wi-Fi I'd expect it to be no more than 1 km from the radar and with the right equipment not too difficult to track down and terminate - given the necessary regulatory authority.

China to blow away smog with DRONES


Re: Not really worse as such

Perhaps somebody could explain who are all these debts owed to.

Mathematicians spark debate with 13 GB proof for Erdős problem


Re: Imagine a random, infinite sequence of numbers containing nothing but +1s and -1s.

And somewhere in that sequence is every other picture you could possibly imagine and, indeed, every other finite sequence you could imagine including arbitrary long sequences of 1's and 0's, the complete text of Wikipedia, the answer to the ultimate problem of life, the universe and everything etc., etc. However I wonder whether you could specify a sub-sequence in the sense of the proof by specifying its content or properties rather than its position? Such content addressability is an everyday aspect of computing, I wonder how this would affect the proof and/or how such a strategy would be excluded?

UK spooks STILL won't release Bletchley Park secrets 70 years on


Re: Zuse Z3

Zuse's Z4 is now on display in Munich. It is, I believe, the third oldest computer in the world and the oldest complete machine. Unfortunately, so I've been told, nobody knows how to adjust the relays so it sits there in silent splendour. As GPO old timers will know, for long term reliable operation electromechanical relays require skillful mechanical adjustment. And fortunately when TNMOC came to restore the WITCH (which I enjoyed programming in the 1960's) retired GPO engineers were available.

Incidentally I find it really sad that there seems to be some silly spat between TNMOC and the Bletchley Park Trust. I've also got some nice photos of the Colossus rebuild which I took when I first visited TNMOC a few years ago before it was moved to its present rather gloomy home. Not sure whether, in the present state of affairs at BP, I could pass them on.

Mars rover Curiosity snaps 'pale blue dot' image of Earth, Moon


Re: For Carl

Commenting on the small blue dot, somebody once said to me "doesn't it make you realise how insignificant we are". I had to say "no, we built that spaceship, we sent it on it's way to the stars; insignificant, I think not".

Thank you Carl.

China ALSO building encryption-cracking quantum computer


Re: Erm...

I've heard an alternative version - "If you owe the bank a million you're in trouble, if you owe the bank a billion, the bank's in trouble" - might need adjustment for inflation ;-)

ALIEN WORLD Beta Pictoris snapped by Earth's Gemini 'scope


Re: Life vs Civilisation

Surely radio emission strengths loose power with the square of the distance not the cube - unless the laws of physics have changed since I was at school. More to the point advanced civilisations are unlikely to waste lots of radio power broadcasting to the stars, like us they will increasingly use tightly focussed beams from downward looking satellites and cable/fibre systems - so much for radio SETI.

The chemical signatures of life are another matter however.

Microsoft Surface sales numbers revealed as SHOCKINGLY HIDEOUS


Re: Too bad

Wouldn't it be easier to port Linux and then run the key MS applications under Wine ?

NASA chief: Earth is DOOMED if we spot a big asteroid at short notice


Re: Acceptable losses?

If the asteroid was disintegrated far enough way some of the fragments would surely miss. A suitably placed explosion would give the fragments extra momentum in all sorts of directions. If the extra momentum were perpendicular to the main track, the fragments would be on a different trajectory, if the extra momentum were along the main track the fragments would reach the Earth impact point sooner or later than the Earth and miss. Of course a lot of fragments and dust would still hit earth but a lot would also miss - unless I'm missing something.

I read the other day that comet C/2013 A1 (possibly up 50km in radius) may impact a planet late next year. This was officially discovered in January 2013 which doesn't give much time to do something about it. Fortunately its heading for Mars not Earth - and just because its well out of the ecliptic plane we've only just noticed it. This doesn't give me much confidence in present threat discovery..

Worst broadband notspots in the UK named and shamed


How reliable are the figures?

A quick Google revealed a large number of "check your broadband speed sites".

So I decided to try them. It's about 1015 and I'm in suburban Wolverhampton. Here's successive download speeds from 10 different measurement sites.

36.7, 53.0, 29.3, 57.6, 39.1, 18.1, 62.1, 56.1, 60.6, 60.0

Virgin media are supposed to provide 60 Mbd so not too many complaints but the variations suggest that either speeds can widely over a short time scale or that some of the measuring tools are not too accurate. In either case I think we ought to know more about the methodology behind the report.

Upload speeds were consistently in the range 2.7-2.9 Mbd.

Another new asteroid-mining firm: 'First commercial space fleet'


In many cases they never started dreaming let alone have stopped.

In 1993 I started using WWW and thought it rather amazing, I'd already been using the Internet's anonymous FTP archives extensively (remember Archie?), the potential was pretty obvious - but trying to persuade university brass to back development of our own resources was another matter. They were more interested in the possibilities of training people to use Microsoft Office.

In 1993 I already had a home computer and home Internet seemed an obvious development. Whether I'd have anticipated a 60 Mb permanently on home connection is another matter.

DEKATRON reborn: Full details on World's Oldest Digital Computer


Re: And it's actually *programmable*

Used to programme this machine back in the 1960's.

The relays are used to decode instructions and set up the required data paths, basic addition and subtraction are purely electronic limited in speed by the switching speed of the cold cathode decatrons. The electronic parts of the addition process took about 30-40 mS + extra for carry cycles. Multiplication used "shift-and-add" - a bit like long multiplication - and required relay intervention to set up the shifted data paths, the operation was so slow you could actually see the partial products build up. Division was similar although the need to count the number of operations made it even slower. The (shifted) divisor was repeatedly subtracted from the dividend until a sign change was detected, it was then added back once and new cycle of subtractions started with an increased shift - again it was possible to watch the quotient being built up.

Incidentally division by zero was a particular problem as the repeated subtraction of zero never resulted in a sign change. If this happened a "watch dog" circuit noted that no new instructions had been read in for some time and, depending on the setting of a control switch, either blew a hooter or shut the machine down.

Addition and subtraction took place directly between memory locations, multiplication and division proceeded via a special memory location called the accumulator.

The dekatrons are visual and it is possible to stand in front of the machine and determine the contents of any memory location by the simple expedient of looking at it. An excellent feature for the introductory programming courses held at Wolverhampton.

Programmes were normally read from paper tape, each instruction being read from tape before execution, this operation contributed significantly to the slowness of the machine. If you wanted a programme loop you need to make the tape into a physical loop using a paste-pot. There was also a technique for incorporating something called a "block number" in amongst the orders on the tape, this functioned in exactly the same way as a label in a more modern programming language.The original "Gloy" paste pot I used in the 1960's was still in the spares box when the machine moved to Bletchley Park!

It was also possible to store instructions in memory (like a modern computer) but with only 90 memory locations this was rarely done. It was actually slower to read instructions from memory than it was to read them from paper tape. [Not quite sure why].

There were further problems with loops, the mechanical readers are rather heavy handed and after several passes had a tendency to poke extra holes in the tape. Solutions included the use of, expensive, linen based paper tape and repeating the "loop body" multiple times on a larger physical tape. I remember one large loop that was routed round an Anglepoise lamp on the other side of the room.

The most interesting task I programmed on this machine was a key (as in door key) design programme for a local firm of lock and key manufacturers [Messrs Chubb]. The problem was that on a mortice key (the sort with sticking pieces of metal called wards) only certain combinations of ward length were valid, a single ward sticking up above its neighbours would be weak, adjacent wards of the same height were a security problem etc.. Along with another schoolboy (I was let off school for a day a week to use the WITCH) we programmed the WITCH to print out all the valid combinations.

Like all machines of its period, the WITCH had what can only be called "presence", a wall of flashing lights, clacking relays, clattering tape readers and the slightly asthmatic whirr of the output printer springing into life.

Remembering the state the machine was in when it reached Bletchley Park, the fact that it has been restored without any significant replacements is a tribute to both the original designers and the restoration team.

Attending the re-boot ceremony I was given a lapel name badge that described me as "Wolverhampton WITCH", I'm keeping it for Halloween!

Boffinry group shakes tin for effort to build Babbage's Analytical Engine



A version of the Difference Engine has been built out of Meccano (so much for engineering tolerances),

see http://www.youtube.com/watch?v=KL_wy-CxBP8

Perhaps the analytical engine team should consider .....................

Pints all round as Register Special Projects hacks hack off feet


Re: There's an opportunity here

Would those be metric pints by any chance?

Sky support dubs Germany 'Hitler's country'

Big Brother

Re: You'll fit right in

On my first visit to Germany a few years ago, I flew into Dusseldorf to catch a train to Essen. DeutscheBahn did their best to make me feel at home, producing a train that was slow, dirty and late. The Ruhr river looked like a country brook. Essen was fascinating, practically every building in the city centre had been destroyed by allied bombing during the (don't mention), except for Mr. Krupp's factory which they'd somehow missed and had since been converted into a branch of Ikea. Wandering around the city on Saturday afternoon (all the shops closed at 4 o'clock) I found myself looking at a row of little Swastikas and pictures of Adolf Hitler - I thought the philatelist's shop could have chosen it's window display more carefully.

NASA's $2.5bn Curiosity rover: An Apple PowerBook on wheels

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BAE - is that British Aerospace Engineering? A British company manufacturing computers, that can't be right surely?

Does Britain really need a space port?


Re: Slightly OT

Skylon gets as much speed as it can whilst still in the atmosphere to take advantage of "free" atmospheric fuel oxidant and then goes up to clear the resistance of the reminder of the atmosphere. The animation shows the early part of the climb to orbit which would be nearly vertical just like the climb to orbit of a conventional rocket.

Incidentally I am puzzled by one aspect of the animation. Skylon is shown travelling east-to-west over Capri, Southern Italy and Sicily. I thought west-to-east orbits were energetically preferable.

Court rejects Tesla’s latest libel spat with Top Gear


Re: Defeating the object.

Hmm. Yes there's an awful lot of hydrogen about, but on this planet, you need energy to separate it from other elements, usually oxygen, where is that coming from - an oil-fired power station perhaps? Hydrogen gas also has a low energy density per unit volume - certainly compared with petroleum - so hydrogen powered vehicles need either huge gas bags, weighty compressed hydrogen cylinders or expensive cryogenic systems.

Vint Cerf: 'The internet is not a human right'


Hear! hear! - but

So you have the right to exploit, the right to extort, the right to misuse the law to your own advantage ...... I find it worrying that so often discussion of rights seem to revolve around what I, as an individual, can do. A duty to consider and care for others less fortunate than oneself is surely every bit as important a part of the human condition as the rights we seem so happy to claim.

When I was younger, we here in England often saw the USA as a big hearted generous open innovative society if a bit vulgar. Alas no more.

What has that got to do with the Internet? Not a lot - but remember that the development of the Internet protocols (TCP etc.,) was funded by the US government who then, apparently, told Berkeley that they couldn't charge for what they'd developed because the tax payers had already paid for it and they shouldn't have to pay twice. I leave it readers to imagine what would happen today.

NASA finds first Earth-sized planets outside the solar system


To be followed by the telephone sanitisers and advertising account executives .......

Google gives £550k to Bletchley Park


Bletchley Park

Great news that the future of Bletchley Park is now more secure.

But I hope restoration and conservation doesn't alter the overwhelming slightly "down-at-heel" 1940's period flavour of the place. Anybody at all interested in the history of computing should make every effort to visit it, and allow a full day.

I also hope the relationship between the National Museum of Computing and the Bletchley Park Trust can be clarified to the benefit of all concerned.

I particularly enjoy going to see the first computer I ever programmed on display rather than hidden and forgotten in a dusty museum store. They've even got a photograph of me standing in front of it 1961 - that's half a century ago.

Slightly off-topic, does anybody know why the movie "Enigma" which was set at Bletchley Park wasn't shot on location?

Dennis Ritchie: The C man who booted Unix


See http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html

Not too sure about the methodology.

And note that it's C excluding derivatives such as C++ (surely it ought to

have been ++C !) and C#


Oh happy memories. My first escape from mainframes, Cobol and Fortran

(and ICL's George 3) was Unix V6, PDP/11's and C, happy hours reading the source

code and eventually fixing two bugs in the kernel source. Gosh I could

read the source code of an operating system - and understand it!


Water like that of Earth's oceans found in comet


So our solar system was originally like many other recently discovered

solar systems with a gas giant close to the star. What caused the disruption

that ejected the gas giant and re-arranged the solar system in its present

life-friendly form? Was it a likely event or something rare and improbable?

I suppose the most likely cause was another star passing close to the solar

system, I've no idea how likely this would be but I imagine most such close

encounters would not result in re-arranging the solar system into a life

friendly form. It is remarkable that after the disruption the solar system

settled into nice stable nearly circular orbits. It also suggests that the inner

planets were not necessarily formed at their current distance from the sun.

Coupled with the need for the "late heavy bombardment" to fill Earth's oceans

the "rare Earth" point of view looks even more convincing.

Faster-than-light back with surprising CERN discovery


Sorry no

Distance on the surface of the Earth ~ 732Km

Straight line distance through the Earth ~ 731.24Km

[Maximum depth is about 10.5 Km assuming smooth

Earth.]That's a difference of ~760m. The quoted 60 nS

difference corresponds to about 18m path length


Boffins step closer to steam-powered Babbage computer

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"The Difference Engine" is a great read.

For a factual account Tom Standage's "Victorian Internet" [1998] is also well worth a read.

Digital store and forward communications networks - just like the Internet -

in the 18th (yes 18th) century.

London rioters should 'loose all benefits'


The army

Would the army want them?

Quiet, astronomers at work



No power line networking!

I bet the local radio hams are happy - until they key up the transmitter.

Rampaging Android takes over Main Street America


Normal Scandinavian Names ?

Last time my wife dragged me to Ikea, I'm sure I saw a light fitting called a FARTYG

Bletchley Park opens U-110 Enigma exhibit


Now just let's get things straight.

The Enigma supplied by the Poles was an early version which none the less provided clear insight into how it operated. That alone was not enough to decrypt Enigma messages. You also needed to know various initial settings which changed on a frequent (daily) basis. The genius of BP was in building machines and procedures for recovering the settings on a regular basis.

The U110 recovery was of the more complex naval Enigma machine, significantly different from

that the Poles had in the 1930's. As well as recovering this machine, vital code books (giving initial settings) were also recovered from U110.

The Colossus proto-computers, of course, had nothing to do with Enigma.

Robert Harris's fictional account "Enigma" gives a good feel of BP and the cracking of Naval Enigma. The movie "Enigma" was, to me, a bit of a disappointment and why wasn't it shot on location at BP?

Rackspace backtracks over toff-proof sign-up process


Misunderstanding names

I also am known by my second Christian name. This caused considerable confusion when work place acquired a clever 'phone system with an extension/user database populated from the staff list. I used to regularly receive 'phone calls asking for "John" - my first Christian name.

To add to the complications I also have three Christian names and I have known systems that address me as Mr. <first Christian name> <third Christian name>.

Too many people making assumptions rather than doing some serious leg work researching the options when designing systems using names. It would be nice if some national or professional agency could give general advice to coders on the ground on such issues, even nicer if they could get it right.

Blighty's Skylon spaceplane faces key tech test in June

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And Strauss's "Blue Danube Waltz" as background music for the orbital rendezvous?

Open source and the sluggish UK public sector


FOSS needs support

About 3 years ago the company where I work part-time wanted a new e-mail system but didn't have any funds for it. An old PC, SuSE Linux and the Courier mail package later they had such a system - which had over 2 years continuous up time until we had a power outage that exceeded the capacity of the UPS. It is also compatible with and integrated with MS Active Directory for user authentication. Support has consisted entirely of adding things that weren't in the original request - such as automatic "sig" addition, archived mail recovery and automatic enrolling of new staff in role-specific group aliases.

Microsoft struck by HTML5 commitment phobia


Geek count

Current figures, for what they're worth, from statcounter are

IE9 2.14%

FF4 7.30 %

I didn't know there were that many geeks!