Wireless Waffle - A whole spectrum of radio related rubbish
The Vl'hurgs and the G'gugvunttssignal strength
Wednesday 31 March, 2010, 03:11 - Amateur Radio
Posted by Administrator
Having seen this... the following somehow came immediately to mind...
It is of course well known that careless talk costs lives, but the full scale of the problem is not always appreciated.

For instance, at the very moment that it was concluded that 'economically speaking, short-wave listening wins hands down' a freak wormhole opened up in the fabric of the quasi-scientific continuum and carried these words far far across almost infinite reaches of space to a distant office where strange and warlike beings were poised on the brink of a frightful regulatory battle.

The two opposing leaders were meeting for the last time.

vl hurg g gugvunttA dreadful silence fell across the conference table as the commander of the RSGB, resplendent with his black jewelled battle antenna, gazed levelly at the Ofcom leader squatting opposite him in a cloud of sweet-smelling spectrum smog, and, with a million sleek and horribly beweaponed lawyers poised to unleash legal hell at his single word of command, challenged the creature to take back what it had said about his latest report on the applicability of EN55022.

The creature stirred in his sickly broiling vapour, and at that very moment the words, 'economically speaking, short-wave listening wins hands down' drifted across the conference table.

Unfortunately, in the Ofcom tongue this was the most dreadful insult imaginable, and there was nothing for it but to wage terrible war.

Eventually, of course, after the bureaucracy in their swish London offices had been decimated, it was realised that the whole thing had been a ghastly mistake, and so the two opposing battle forces settled their few remaining differences in order to launch a joint attack on Comtrend - now positively identified as the source of the original offence.

For thousands more pounds the mighty forces tore across the empty wastes of the Earth and finally dived screaming on to the first factory in China they came across - where due to a terrible miscalculation of emissions the entire battle force was taken to court for breaching the local EMC regulations and locked up in a prison for the ensuing millennia.

Those who study the complex interplay of cause and effect in the history of the the radio spectrum say that this sort of thing is going on all the time, but that we are powerless to prevent it.

'It's just life,' they say.

With respect to Douglas Adams
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We're Jammin' (Part III)signal strength
Wednesday 24 March, 2010, 14:55 - Spectrum Management, Satellites
Posted by Administrator
ConstellationGPSFirst off, let's get a few things straight. GPS works by using a constellation of about 30 medium earth orbit (MEO) satellites run by the US military which go whizzing around the earth twice every day at a height of 20,000 km to transmit position and time information to receivers on the ground. From this information GPS receivers then can work out where they are. This means that the only person who knows your location is you - there is no path back to the satellite which somehow covertly tells the satellite where you are.

Thus GPS devices in themselves can not be used to 'track' the location of users. What they do provide is location information which could then be sent on via some other (radio) connection to enable someones location to be tracked. Standard in-car navigation systems do not have such a facility built in and thus using one does not alert the authorities (or anyone else for that matter) to your location.

That aside, there are in increasing number of uses to which GPS is being put in which the location information it provides is used for control purposes. For example, there are anti-social behaviour tags which monitor the location of offenders and send a signal to the local police or council if the person wearing it goes outside a pre-determined area (or indeed goes inside a particular area).

Similarly, knowing where a vehicle is (for example by sending the GPS location back to a central point via a GSM phone) can be used for road toll or car insurance calculation. There is therefore a growing 'demand' for devices which can stop the GPS receiver working so that the location information for tracking people or cars is not available. Such devices are known as GPS jammers and work in much the same way as the jammers used by various governments to stop international broadcasters.

jamming 2The most basic GPS jammers operate by producing a high power signal on the main frequency used by GPS receivers, strong enough to ensure that the GPS receiver can no longer hear the (very weak) signals from the GPS satellites and therefore thinks it has lost them and stops working. However, receiver manufacturers have gotten wise to such wheezes and have managed to find ways to overcome this 'carrier' jamming. More sophisticated jammers closely mimic the GPS signal so that not only is the receiver overwhelmed by the local interference but it becomes far more difficult to overcome the jamming as it looks just like a valid GPS signal.

The problem, though, with such jammers is that they don't just wipe out GPS reception by the receiver they are intending to interrupt, but can knock out GPS reception over quite a wide area. Even basic, low power devices (which typically use transmitter powers of around 10 milliWatts) can produce signals strong enough to stop GPS receivers working over a range of several hundred metres. More powerful devices (and there are some easy to get hold of devices which put out a Watt or more) can cause problems for GPS receivers over ranges of over a mile. So without knowing it, someone trying to defeat the GPS monitoring device put in their company car to monitor their movements can unintentionally end up causing aircraft or ships to not be able to identify where they are either.

Now, of course, GPS jammers are illegal to use as they intentionally cause interference which is not just unlawful in that you generally need a licence for any radio transmitter, but that causing harmful interference is a particularly scandalous deed. The problem of GPS jammers is well recognised by the authorities and the impacts of their use so severe that they are one of the very few devices that organisations such as eBay have been asked to stop the selling of on their web-site (try searching there for 'GPS jammer' and you won't find a single one on offer). However, there are ways and means of getting hold of them and like anything that is useful in a 'getting out of paying for something' or 'getting around the law' way, it's almost certain that their sale will continue with devices popping up from new suppliers as the authorities crack down on sellers one by one.

gps signal jammedWhilst all this might sound a bit like scaremongering, with aircraft falling out of the sky, that's not the real problem (aircraft don't crash just because they lose their GPS signal). Earlier it was mentioned that GPS satellites transmit both position and time information. The time information is used for a very wide range of applications, from synchronising digital transmitter networks, to ensuring that trades on the stock market are correctly time-stamped. Imagine if these timing signals were lost - TV transmitters would fail and the stock market would come crashing down, so no Coronation Street and no hefty bonuses for city workers (whilst the last of these might not seem too severe, losing Coronation Street would be a national crisis).

GPS jammers have been described as a 'clear and present danger' and much is being done to try and minimise both their availability and their impact, but it seems their use will continue, and most likely continue to grow. If you feel like popping out and buying one for any reason, think again, you might as well drop a teaspoon of polonium-210 in your local neighbourhood resevoir - the consequences of both for society may not be that far apart!
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RSGB Spectrum Defence Fundsignal strength
Sunday 31 January, 2010, 09:39 - Amateur Radio
Posted by Administrator
Sometimes Wireless Waffle can be rather frivolous and irreverent but today is not one of those days. On many previous occasions, Wireless Waffle has gone on about the threat to short-wave radio caused by power line telecoms (PLT), power line adaptors (PLA), broadband over power-line (BPL) and blaufunk zür electrische Breitband über bezahlen (BLZEBUB as it is known in the Germany) yet they continue to proliferate. But in the UK at least, it seems that there is going to be a properly monunted challenge to the blatant flouting of the law that these devices do on a daily basis.

Having thought that the UK spectrum regulator, Ofcom, would respond to the concerns of UK radio users, the Radio Society of Great Britain (RSGB), the body which represents radio amateurs, has played a very professional deck of cards to date; demonstrating that the equipment concerned does not conform to the necessary standards and using existing legislation and regulation to request that Ofcom take action. Ofcom's response, however, has been very disappointing, and seems to be acting on the basis that few complaints equals few problems. Presumably very few people complain when a vehicle knocks them down and kills them, so perhaps we should cease to be concerned about enforcing speed limits?

Ofcom seems to be following a circular argument that, on one hand, radio regulations don't apply because the devices which cause the problem are not intentionally generating radio transmissions; and on the other, that electromagnetic compatibility (EMC) regulations don't apply to the radiation they do cause, as EMC is not about controlling radiation from devices - as any such radiations are meant to be covered by radio regulations. It even turned down a sensible proposal from the German regulator, the Bundes Netz Argentur (BNetzA) for a purpose-designed specification for these types of device to ensure they didn't fall down the tiny pothole that might just exist between the two sets of regulations.

Several petitions have even been raised with Number 10 Downing Street (the Prime Minister's office as opposed to the Farnham Healing Centre) to which Ofcom's response has been equally lacklustre. 'No biggy...' seems to paraphrase their attitude.

rsgbspectrumfundSo kudos then to the RSGB for putting down their playing cards and taking up arms against the problem (whether you class the problem as the devices or as Ofcom) and establishing a Spectrum Defence Fund (SDF). The RSGB claim that to challenge Ofcom through the relevant legal channels will cost in the region of £75,000. The RSGB are asking anyone and everyone who has an interest in short-wave listening, either for pleasure or professionally, to put their hands in their pockets or break open their piggy banks and donate some money to the cause. They point out that if every radio amateur in the UK donated just £5, they would soon reach their target. On the other hand, if only a couple of thousand people donate the same amount, they will miss the target by a large margin.

rsgb in actionSome may question whether or not it is right for the RSGB to become so overtly political in its outlook given the fact that it has only really used its deck of cards to play snap in the past and has never ventured into more risky territory (such as whist for example), let alone expose itself to the dangers of games such as poker. For the past century, or thereabouts, it has been a forum for sharing news and information for the amateur community in the UK and although it has responded to many Ofcom consultations, it has done this in the role of a semi-passive observer: a (card playing) grandfather who passes down occasional nuggets of experience to the go-getting upstart grandchildren who now inhabit the spectrum. And rightly so. The RSGB should be a centre of expertise; a wise old sage to whom its members, and the wider UK radio community can turn to answer those difficult questions. But the threat from PLT/PLA/BPL/BLZEBUB is very real and it's time for granddad to stand up and batter the kids around the ears with a solid oak walking stick until they sit down and stop acting like spoilt brats.

The threat to the radio frequencies used by radio amateurs, however, comes from more than just BLZEBUB. Radio spectrum is becoming a very valuable commodity and amateurs sit on real-estate which in the UK alone would be valued at several million pounds if it were open to the markets to purchase. There is no evidence of an immediate threat in this regard, and no queues have formed to offer granddad an especially large pension in return for his deck, but if the amateur community does not keep its eyes open, someone is likely to creep up on granddad whilst he is out for a walk and take his wallet and keys, and his solid oak walking stick.

So the time has come for radio amateurs and short-wave listeners of all kinds across the United Kingdom to unite and support granddad. Why not have a night listening to the radio and remind yourself of what it's all about. Not Danny DJ spinning the same old tunes on Radio Local FM, but tune around the short-wave bands and see what you can hear. With sunspots beginning to acne the face of the sun again, you might just be surprised at what you can hear. And when you have rekindled your love of radio, pop along to the RSGB web-site and donate a few quid. Imagine what life would be like without your other favourite pass-times, whether beer, wine, fags or whatever. In fact, go without for a week. Then think how it would feel if you couldn't use your short-wave radio again and give the money you saved that week to the RSGB spectrum fund. In return, Wireless Waffle intends to donate all the money made from the various advertisements which are scattered around the site to the RSGB Spectrum Defence Fund. We'll let you know how much this is in a couple of months time...
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Number Station Bingosignal strength
Friday 1 January, 2010, 00:14 - Pirate/Clandestine
Posted by Administrator
Regulars to the pages of Wireless Waffle will realise that we have an inate (or should that be 'inert') fascination with short wave radio. And nothing is more mysterious and intriguing on short wave than the many spy broadcasts which usually take the form of a string of numbers or letters read out in a mechanical fashion by a pre-recorded male or female voice. A bit like the speaking clock for spooks.

mint spies bingoOne of the most famous spy stations, the Lincolnshire Poacher (which was allegedly broadcast from Cyprus), ceased transmissions in 2008 and it rumour has it that its sister station, Cherry Ripe (latterly broadcast from Australia) also ceased transmissions towards the end of 2009. Which leaves fans of these funky but furtive broadcasts with a big hole in their social calendar (not that such fans had much of a social calendar to begin with).

But all is not lost. Thanks to the Conet project and web designer Kevan Davis fans can now enjoy:

* Number Station Bingo

This excellent game will keep you occupied (but not in the same way as the US forces in Iraq) for literally minutes. If you win, it is customary to shout 'Badabingo, green stick in the green hole' though for security reasons we obviously cannot explain why this is so.
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