Military jamming of GPS in Scotland suspended

kyleview

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I know there is another post on this a week old, but focuses on why jam at all.

This post relates as to why it came as a surprise to the fishing community in the NW of Scotland when it actually happened - http://www.bbc.co.uk/news/uk-scotland-highlands-islands-15242835 - as the MOD posted it on the web for all to see in early September.

The MCA give warning for all sorts of things regularly - submarine exercise areas, buoys adrift, right down to logs floating in the sea, etc, etc. I would have thought that such a major known outage like this in a particular area would have been broadcast from the local coastguard as part of the regular 4 hour broadcasts.

Interesting to understand why there has been such a disconnect between the various parties in this instance.
 
I would have thought that such a major known outage like this in a particular area would have been broadcast from the local coastguard as part of the regular 4 hour broadcasts.

It was. From your link; "both Aberdeen and Stornoway coastguards have been transmitting regular warning broadcasts on VHF, notifying mariners that the operations will take place."

And on Navtex.

Anyway, we've known about this for weeks. What's the problem?
 
Having worked with / despite the military, I wouldn't be at all surprised if some sort of 'secrets' regulation prevented too much publicity.

Naturally this would be no snag at all to the Russians/Chinese/Al Queada/Gaddafi/ Tescos but a right pain for UK sailors...:rolleyes:
 
Sadly, fisherfolk and others have come to accept the facility of using GPS.

No one has a right to the GPS service and as a consequence, if it fails or is turned off or jammed, Too bad. As Sandyman states, get your charts and sextant out! :rolleyes:

Too many people have come to rely on it including the DSC facility and this is a problem which civilian users will have to live with and learn to cope.

The jammer that was promoted in an earlier post will not 'jam' the GPS service at all. It is a 'in-cab device', short-range, which will overload the 'front-end' of the lorry drivers GPS receiver and stop it from receiving the satellite and therefore sending a tracking position update via the GSM telephone service.

When TETRA was rolled out a few years ago, I was heavily involved in the problems it caused as it 'jammed' loads of UHF services (in-house wireless alarms, High-end Thatcham car alarm systems, garage door openers). All these UHF devices were using cheap TRF front-end receivers and therefore received anything within a 20 MHz wide pass-band including TETRA!! Even though the transmitters complied with the relevant specification (MPT 13xx etc and ETSI 300.xxx), the receivers did not need to be tested for compliance and therefore the manufacturers had used cheap designs and not gone for a filtered superhet front end receiver. The same with modern chart-plotters designed for domestic use.

Just look at the very serious problems now being 'discovered' in the USA as they roll out the new Lightsqaured facility. They are now meeting the same problems experienced by the UHF systems mentioned above. Soon this RF frequency band will be opened up for use here in the UK! :eek:

http://www.fiercegovernmentit.com/story/lightsquared-gps-dod-fcc-fault-interference/2011-10-06

If you want a robust GPS receiver then you need effective front end filters and hi-gain (5-pole Chebyshev or Butterworth filters or better!).

I spent 25 years with the Radiocommunications Agency and Ofcom and met these problems head on and sadly they will exist whilst the buying public want radio devices which works but are cheap.

I am standing by to make RF filters for my onboard electronic systems when it all goes tits up due to the roll-out of some new fangled radio service like Lightsquared in the USA! :rolleyes:
 
#6 Today, 12:54
lenseman
Registered User Join Date: Jun 2006
Location: South East Coast - United Kingdom
Posts: 4,574



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Sadly, fisherfolk and others have come to accept the facility of using GPS.
"No one has a right to the GPS service and as a consequence, if it fails or is turned off or jammed, Too bad. As Sandyman states, get your charts and sextant out!
Too many people have come to rely on it including the DSC facility and this is a problem which civilian users will have to live with and learn to cope."


The above is a bit of a blinkered view isn't it. Several hundred years ago people probably made similar statements about accurate clocks. Remember when electronic calculators were banned from examinations??
 
#6 Today, 12:54
lenseman
Registered User Join Date: Jun 2006
Location: South East Coast - United Kingdom
Posts: 4,574



--------------------------------------------------------------------------------

Sadly, fisherfolk and others have come to accept the facility of using GPS.
"No one has a right to the GPS service and as a consequence, if it fails or is turned off or jammed, Too bad. As Sandyman states, get your charts and sextant out!
Too many people have come to rely on it including the DSC facility and this is a problem which civilian users will have to live with and learn to cope."


The above is a bit of a blinkered view isn't it. Several hundred years ago people probably made similar statements about accurate clocks. Remember when electronic calculators were banned from examinations??

Well, I suppose that if any of us were actually paying for the GPS service, we could justifiably complain. As it stands, it belongs to the American military who, quite remarkably, let us have it for free - we don't really have a leg to stand on if the military decide to play with it from time to time.

The fact that they do was part of the EU justification for chucking vast amounts of money down the Galileo black hole - feel free to make donations!
 
.......
Remember when electronic calculators were banned from examinations??

I think you are way out of date. Electronic calculators are not allowed in examinations to this very day. It certainly depends on the examination in question, but at all levels of Mathematics, calculators are not allowed in at least one examination paper at GCSE and GCE. :rolleyes:

Please do not try and contradict me as this is my profession.
 
I think you are way out of date. Electronic calculators are not allowed in examinations to this very day. It certainly depends on the examination in question, but at all levels of Mathematics, calculators are not allowed in at least one examination paper at GCSE and GCE. :rolleyes:

Please do not try and contradict me as this is my profession.

Though, argueably, calculators are of no benefit in mathematics exams - only in arithmetic exams...
 
Though, argueably, calculators are of no benefit in mathematics exams - only in arithmetic exams...

Why are calculators of no benefit ? Please explain what you mean. :confused:

At school I used tables - log tables, trig tables, square and root tables, etc. I can see the benefit of a calculator and I am fascinated that I am obviously missing something and have been for the last 30+ years.
 
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Why are calculators of no benefit ? Please explain what you mean. :confused:

At school I used tables - log tables, trig tables, square and root tables, etc. I can see the benefit of a calculator and I am fascinated that I am obviously missing something and have been for the last 30+ years.

Well, as my old university maths professor would have said, messing about with numbers is arithmetic, messing about with concepts is mathematics. He was an excellent mathematician, but incapable of reliably adding three numbers together.

Broadly speaking, the process of discovering the equation for the derivative of x with regards to y in "x = y^n" from first principles is mathematics, applying that formula to calculate dy/dx for y=7 in "x=y^4.5" is arithmetic. A calculator is great for the latter, but doesn't help in the former.
 
Well, as my old university maths professor would have said, messing about with numbers is arithmetic, messing about with concepts is mathematics. He was an excellent mathematician, but incapable of reliably adding three numbers together.

Broadly speaking, the process of discovering the equation for the derivative of x with regards to y in "x = y^n" from first principles is mathematics, applying that formula to calculate dy/dx for y=7 in "x=y^4.5" is arithmetic. A calculator is great for the latter, but doesn't help in the former.

Now I understand. So, to solve problems the two are inextricably linked. Mathematics is a tool required to solve problems and arithmetic is the tool required to evaluate so that the solution may be used in real life applications. :)

Thank you.

However, I'm not sure that the "man in the street" would always appreciate the difference.

Going back to your example, I think more people would understand the principles if you had used y = f(x) in conjunction with dy/dx, rather than x = g(y). Just a thought .....
 
Now I understand. So, to solve problems the two are inextricably linked. Mathematics is a tool required to solve problems and arithmetic is the tool required to evaluate so that the solution may be used in real life applications. :)

Thank you.

However, I'm not sure that the "man in the street" would always appreciate the difference.

Going back to your example, I think more people would understand the principles if you had used y = f(x) in conjunction with dy/dx, rather than x = g(y). Just a thought .....

And your final point is related - x, y, z are all just symbols - I could just have used "squiggle", "splodge" and "splat". Sorry - just re-read your post and realised that I had mistyped - forget that last one!

I suppose you could say that arithmetic is the application of mathmatics to solve real world problems. My maths professor would have said that there were very few numbers in mathmatics, you seldom need the ability to do much more than add or subtract one.

We have friends who are a married couple - the guy is a very good engineer and his wife is an Oxford first in mathematics. He was chuckling with me a year or two ago because they had been discussing some arithmetical problem and she suddenly remarked "Oh, are you saying that PI is the ratio of the diameter to the circumference of a circle?" She had been close to the top of her class in a maths degree course at Oxford - which is no mean feat - but the significance of PI in spherical geometry was uncomfortably close to arithmetic for her!
 
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Well, as my old university maths professor would have said, messing about with numbers is arithmetic, messing about with concepts is mathematics. He was an excellent mathematician, but incapable of reliably adding three numbers together.

Broadly speaking, the process of discovering the equation for the derivative of x with regards to y in "x = y^n" from first principles is mathematics, applying that formula to calculate dy/dx for y=7 in "x=y^4.5" is arithmetic. A calculator is great for the latter, but doesn't help in the former.

I once ran in an election for a club treasurer at University. The other candidate was a a mathematician; I am a geologist. My platform was that, as I wasn't a mathematician, I would be able to add and subtract more reliably then he could :)

Mathematics has little to do with arithmetic, once you get past primary school level.
 
"but at all levels of Mathematics, calculators are not allowed in at least one examination paper at GCSE and GCE."

I would not not personally describe "one examination paper at GCSE and GCE" as "all levels of mathematics"

"Please do not contradict me as this is my profession" - interesting approach to teaching but how effective I wonder?
 
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However, I'm not sure that the "man in the street" would always appreciate the difference.

Quite, which is why people like Maby like to make the point :)

If you're a maths teacher I'm somewhat surprised the "if it has numbers it's mere arithmetic" type of saying is new to you.

Pete
 
Quite, which is why people like Maby like to make the point :)

If you're a maths teacher I'm somewhat surprised the "if it has numbers it's mere arithmetic" type of saying is new to you.

Pete

I'm not sure if I should be insulted by that, or not! Mathemetics and arithmetic are two very different things - arithmetic does depend on mathmatics, but not the other way round. My mother is fantastic at arithmetic, but has no understanding of mathematics at all.
 
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