Wireless Waffle - A whole spectrum of radio related rubbish

It's a Long Wave from Tipperarysignal strength
Wednesday 22 March, 2006, 10:16 - Licensed
According to Isle of Mann International Broadcasting (IOMIB) around 75% of radios have the long wave band on them. But when was the last time you tuned into long wave? For the cricket coverage on BBC Radio 4? Or when Atlantic 252 was pumping out its 'You're never more than a minute away from the next minute' style of upbeat pop music? Other than that, unless you live outside the UK and keep in touch by listening to Radio 4, you probably rarely switch your radio to the 'LW' setting. But there are a number of broadcasters who are banking that they can start commercial services on long wave and get you to tune in to listen to their programmes - and their advertisements!

atlantic252In the mid 1990's when Atlantic 252 was in its heyday, three other companies figured that they too could launch successful long-wave radio services for the UK. Of the three, two are still planning their launch nearly 10 years later and one has given up. A combination of political, financial and environmental obstacles have prevented any of the three stations from finally getting on-air and a question has to hang over the two who still have plans as to whether they will ever launch.

The aforementioned IOMIB (whose other web-site can be found at longwaveradio.com) plan to launch a service tentively named 'MusicMann279' on 279kHz with a power of 500kW. Their transmitter site was originally planned to be on the mainland of the Isle of Mann, however due to local objections and despite planning to use a Cross-Field Antenna which is much smaller than a conventional antenna (and some would argue that its performance is in proportion to its dimensions), they now plan to build a platform in the Bahama Bank just off the island. There have been various rumours about a possible launch date for the service and plenty of speculation about what kind of service it might be, but so far no real evidence of any progress. There most recent rumours circulating are that the service will launch in the summer of 2006 at reduced power under the name of 'Caroline 279'. long waveI somewhat doubt this latest rumour as there are a couple of aeronautical navigation beacons (non-directional beacons or NDB's), one near RAF Northolt on 277 kHz and one near RAF Lyneham on 282 kHz which are still in operation and in daily use. The interference to these beacons from the proposed Isle of Mann service would be so strong that they would have to change frequency and... they haven't!

The station which has now given up the ghost was known as variously 'Delta 171' or 'The Lounge' and was intended to provide an adult orientated middle-of-the-road, 'BBC Radio 2' style service, broadcasting out of the Netherlands. In the same way as in the Isle of Mann, there were local environmental objections to having a 500kW (half a MegaWatt!) transmitter on the doorstep so Delta was forced to consider a platform in the North Sea. This proved too expensive and the project collapsed in 2000 when the licence for the long wave frequency which had been awarded by the Dutch regulator expired and was not renewed.

northernlightsThe final station which still claims to be planning a launch is 'Cruisin 216' which will carry Christian programming. Cruisin intends to operate out of southern Norway to put its signal into the UK, however the frequency they have of 216 kHz is shared with Radio Monte Carlo (RMC-Info) who use a powerful 1.4 MegaWatt transmitter from Roumoules in south western France. Cruisin's own web-site indicates that their signal in London will be approximately 13dB (20 times) stronger than that from RMC-Info, however the same article on their web-site also shows that this is insufficient for interference not to be a problem. The fact is that the RMC transmitter already puts in a good and listenable signal into London and most of the south eastern corner of England so the signal from Norway would have to be whopping to compete. In Scotland and the north of England they might stand a chance - of course being a religious station, there may be someone up there lending them a helping hand!
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Ahoy There!signal strength
Thursday 9 March, 2006, 15:24 - Pirate/Clandestine
piratemanWith all this talk of pirate radio, a question that often gets asked is, "But I've never heard a pirate station; where do I find one?". Yes, there are those who have yet to stumble across the skull and crossbones of the airwaves!

The best place to look is on the FM dial of your radio. But with so many stations around, how do you know if the station you are listening to is a pirate or a legal station? There are a few clues which even the least experience listener should be able to fathom:

1. The signal is in mono. Most pirate stations broadcast in mono, however, this is not at all conclusive as many RSL stations do this too and further, some pirates broadcast in stereo.

2. There is no RDS. Including RDS can be complicated for some pirates so they choose not to use it. This is still not totally conculsive though, as some RSL stations have no RDS either.

scrollingrds3. The RDS is 'scrolling' (i.e. it is changing to display a message - as shown here on the right). Legal stations in Europe are obliged by the European Commission to use a static name on their RDS display to make sure drivers aren't distracted. Pirates, however, can change the name of the station to display messages on RDS equipped radios. A few legal stations (not in the UK though) do scroll or rotate the message on the RDS display so this too isn't totally conclusive, however reading the message might give a good indication. If it's advertising a party at a local night club then chances are you're listening to a local pirate!

4. The presenter doesn't have a middle-class accent! This is especially true on FM stations in the UK, where legal stations try to recruit presenters with unoffensive voices that won't turn listeners off. As pirate stations are usually there to promote the music or club nights, whether the presenter can pronounce 'Douglas St.John Farquhar' correctly really doesn't matter!

piratewoman5. The phone number being given out to contact the station is a mobile number (all mobile numbers begin with '07' in the UK). How many legal stations do you know who would, or would need to, use a mobile number for calls to the studio? Further, if you're requested to leave 'missed calls', i.e. to phone the number but not let it answer, you're almost certainly onto a pirate. This is a way to show you are listening without having to spend a single penny on phone calls - quite smart really!

Of course there are other clues, such as the frequency being used (if it's in the middle of the band used for national BBC stations but isn't a BBC station then it's most likely a pirate), but the ones above don't require any technical knowledge. You're more likely to find a pirate station on FM if you live in, or near, a major city than if you live out in the countryside, but you might be surprised.

Another place to find pirates is in the radio no man's land just at the edges of the normal short-wave broadcast bands, especially the lower frequency bands. Why the lower frequency bands in particular - they're better for broadcasting to nearby areas and tend to be more reliable throughout the daily propagation cycle. Good places to listen for pirate short-wave stations are:

* 3800-3950 and 4000-4100 kHz, either side of the 75m broadcast band
* 5750-5900 and 6200-6400 kHz, either side of the 49m broadcast band
* 6800-7000 and 7350-7600 kHz, either side of the 41m broadcast band (avoiding the 40m amateur band too)
* 9300-9400 and 9900-10000 kHz, either side of the 31m broadcast band

And so on either side of the other short wave broadcast bands too... Though the use of frequencies above about 10 MHz is rarer, there are examples such as Alfa Lima on 15070 (± a bit) and 21900 (± a bit) kHz and WR International on 12256 kHz.

piratelistenerOne final place you might come across a pirate station is on the medium wave (MW) band. Most stations prefer FM for local broadcasting as the antennas are smaller and the equipment easier to get hold of, but a few stations do use MW. Radio Free London used to put out a good signal across London on 819 kHz and there are quite a few stations (particularly in continental Europe) who inhabit the no man's land just off the end of the MW band between 1611 and 1640 kHz.

Of course I couldn't possibly condone any activity which would lead you to listen to a pirate and thus break the law in doing so. But at least now you might be able to stop yourself from committing this heinous crime before you get caught!
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More FM licences in London?signal strength
Monday 19 December, 2005, 15:31 - Licensed
For some time now, I've been intrigued by suggestions that Ofcom (and its predecessor the Radio Authority) is toying with the idea of issuing further licences for FM radio stations in London. Whilst the FM band in London is undoubtedly alive with stations, there is still a relatively limited number of stations on-air compared to many other major cities and the variety of programming they offer is even smaller. There is certainly commercial scope for more FM stations in London.

Currently on FM in London there are 14 London-wide and 7 local stations which are, in frequency order:

88.8/89.1 BBC Radio 2 (the lower frequency is transmitted with a power of 4kW from Crystal Palace and the higher with a power of 250kW from Wrotham, on the eastern outskirts of London. The same pattern is true for the other BBC national stations and for Classic FM)
91.0/91.3 BBC Radio 3
london93.2/93.5 BBC Radio 4
94.9 BBC London
95.8 Capital FM
96.9 Choice FM (South London)
97.3 LBC
98.5/98.8 BBC Radio 1
100.0 Kiss FM
100.6/100.9 Classic FM
102.2 Smooth FM
103.3 London Greek Radio (North London)
104.9 XFM
105.4 Magic FM
105.8 Virgin Radio
106.2 Heart 106.2
106.8 Time FM (South East London)
107.1 Choice FM (North London)
107.3 Time FM (South East London)
107.5 Time FM (South East London)
107.8 Radio Jackie

In addition to these stations, there are numerous other BBC and commercial radio stations whose broadcasts overlap from their primary coverage area into the outskirts of London, as well as many BBC relay stations to cover gaps in coverage from the main transmitter sites.

In early 2000 the Radiocommunications Agency, the Radio Authority (both now integrated into Ofcom) and the BBC conducted a study into the possibility of licensing more FM radio stations. The study considered the potential for additional stations in the FM band and sought, in particular, to identify allocations that might be used to provide new services in the London (and Leeds) area. To try and see whether it might be possible to fit more stations on the FM dial in London, the study made some very odd assumptions about what frequencies might be used in London. It took the assumption that instead of adding or re-planning stations to free up frequencies, that from 94.9 and 102.2 MHz upwards, there would be a station in London every 400 kHz (i.e. 94.9, 95.3, 95.7... and 102.2, 102.6, 103.0, etc...) and then looked at the impact that these stations would have on neighbouring stations to whom they would cause interference.

The study concluded that 'In the London area, it was found that there appeared to be some opportunity for the accommodation of further city-wide services, if the need for some re-planning of the network is accepted. For a small number of such additional services it may be that the 'cost' of the re-planning would be limited to changes in the frequencies of surrounding services and a relatively small loss of coverage by a few surrounding services. It should be noted that this study was not required to consider the constraints imposed by continental interference. If this is taken into account there will be less scope for additional services, particularly in the London area.'. Further it added that 'The scope for use of the BBC national network sub-bands was limited by the large number of high-power transmitters in this part of the spectrum. One frequency was identified, however, which might be used to provide additional London-wide service at the expense of current BBC coverage.'.

So what were the frequencies that were identified for potential new London-wide stations, and what has happened since? Well, the frequency which was identified that could be used in London with impact only on listeners in Reigate (Mercury FM on 102.7 MHz which would move to 103.6 MHz) and Chelmsford (Essex FM on 102.6 MHz which would move to 102.8 MHz) was 102.6 MHz (Fox FM in Oxford would also move from 102.6 MHz to 102.4 MHz), and the frequency in the BBC national sub-band that was identified was 92.5 MHz, which it was claimed would upset virtually all the listeners to the BBC Radio 4 service in Guildford on 92.5 MHz who instead of their current 4kW service would get a 50W low-power service on 93.7 MHz. It would seem that since the publication of this report, nothing has happened. No action was taken by any of the parties involved to instigate any changes which might bring about a new license.

Rumours have since surfaced that the frequency of 87.6 MHz might also be used in London. This frequency (actually any frequency in the band 87.6 to 87.9 MHz) is currently reserved for low-power RSL stations, however there is no regulatory reason why a new, high-power, London-wide service could not use this frequency (with the possible problem of the need to co-ordinate with RTL on 87.6 in Lens in northern France). Whilst this would restrict the potential for RSL stations, it would not cause interference to any other UK stations as the band is otherwise unused. Further, the 3 Time FM stations in neighbouring parts of south east London which were previously different stations could now be consolidated onto a single frequency and the band between 106.8 and 107.5 re-arranged to release another London-wide assignment. It has also been postulated that a frequency around 101.6 MHz could be used for a London-wide service (subject to finding a new home for Kent based KM-FM on 101.6 MHz and possibly Ten-17 in Harlow on 101.7 MHz). The original study did not consider the 107 MHz frequency range, nor did it consider 101.6 MHz.

So potentially there are five frequencies which could be released for new stations: 87.6, 92.5, 101.6, 102.6 and somewhere around 107 MHz. With the exception of 87.6 MHz, none of these provides an interference free answer to new London-wide stations, but there seems to be no reason why Ofcom could not look to offer new licenses in London. With the propensity of pirate stations in the capital, there is clearly excessive demand for stations, so why is Ofcom so reluctant to consider a new station or two?

Maybe there is pressure from the existing licensees not to introduce further competition, whilst there is clearly competition between the existing stations, working together as a cartel to block any additional competition is clearly in all of their commercial interests. Maybe Ofcom is busy with other things (for example the raft of community licences recently issued). Or maybe it's just that the people who looked at the problem in the first place have now moved on since the reorganisation that formed Ofcom and no one has been tasked with reviewing the study and taking the necessary action. I'm not sure that there's anything that can be done to 'gee-up' Ofcom, however I felt that raking up the old muck again might just stir some action somewhere.
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Roof Raiderssignal strength
Thursday 1 December, 2005, 09:38 - Pirate/Clandestine
Towards the beginning of November this year, Ofcom conducted a massive series of raids on pirate radio stations in London, and event considered news-worthy even by the BBC.

The operation closed 53 pirate FM stations in London and whilst some of the bigger stations are now back on-air, for some stations, losing a transmitter may mark the end of their broadcasts for some time. One station (On Top FM) also had a studio raid which can be devastating, and is certainly much more difficult to recover from.

What is interesting about this surge of activity by Ofcom is not that it was long overdue, or that it was so widespread, but was some of the 'anti-pirate' propaganda that Ofcom, a supposedly respectable body, spouted in their press release.

"Illegal broadcasting causes interference to the radios used by critical safety of life services such as the London Fire Brigade and National Air Traffic Services (NATS)."

firemanLet's examine this statement. The London Fire Brigade uses frequencies of 70.5 - 71.5 MHz paired with 80.0 - 82.5 MHz, 148.825 MHz (for pagers), various frequencies between 450 and 453 MHz paired with 464.9 - 467.9 and 457 - 457.5 paired with 462.5 - 463 MHz. Now unless I am mistaken, none of these frequencies are directly affected by transmissions in the FM band (87.5 - 108 MHz) otherwise they would receive interference every day from the legal stations. Indeed other than for the fourth harmonics of transmitters on 90-90.6, 93-93.5 (actually BBC Radio 4 in London), 91.4-91.5 and 92.5-92.6 MHz, it's difficult to see where their problem arises. So if the Fire Service are suffering interference from pirate transmissions it is probably from one of two sources:

(1) The FM transmitters used by the pirates are of such low quality that they emit spurious signals on lots of frequencies. This is certainly possible, especially given the low-cost nature of the transmitters that pirates use, however the chances are that any transmitters prone to spurious emissions will be tracked down immediately as they will be causing interference to potentially hundreds of users.

(2) It is not the FM transmitters that cause the problem but is, instead, the link transmitters which are used to connect the pirates' studios to the transmitter site. Such links normally operate either in Band I (47 - 68 MHz) or at microwave frequencies. Microwave links are hardly likely to cause interference but it is feasible that the Band I links might if their frequencies co-incided with those used by the Fire Service. However, I doubt that any pirate would use a frequency knowing that it might interfere with the emergency services, even though they are operating illegally, they are not stupid enough to intentionally cause interference and risk the wrath of Ofcom.

radiomoldovalogoThere is one other possibility. The frequencies used by the Fire Service in the UK are used in some Eastern European countries for FM broadcasting! The 'OIRT' band covers 66 - 74 MHz and high-power transmitters still provide service in countries such as Russia, Moldova and Hungary. During certain propagation conditions, such stations are often heard in the UK (they do use high powers after all) and whilst I suspect that most firemen would know the difference between Russian and English, if they just hear music over their radio system they are going to assume it's a pirate.

So do the pirates cause interference to the Fire Service or not? Well I have no reason to doubt John Anthony, London Fire Brigade Assistant Commissioner who claims that, "... radio transmissions interfere with, and sometimes entirely disable, the communications systems the London Fire Brigade relies on." But is it really pirates or could it be the Russians instead?

vorNext onto the Air Traffic Service. They use many frequencies but in particular use 108 - 137 MHz which is directly adjacent to the FM band. A report from 1997, 'Investigation of Interference Sources and Mechanisms...' showed that illegal transmitters were a constant source of interference to both navigation and communication. This is easier to understand as spurious emissions from a transmitter are usually close in frequency to the main transmission thus spurii in the band 108 - 137 MHz are not unlikely. Thus I don't necessarily doubt 'A spokesman for NATS' who said, "Unauthorised broadcasts on or close to frequencies used by air traffic controllers can interfere with the passing of vital information between air traffic controllers and pilots. They can also affect the navigation aids used as landmarks." Point to Ofcom!

"Illegal broadcasting also causes interference to legitimate radio stations, denying hundreds of thousands of listeners the opportunity to hear their favourite programmes."

Does it now? Well in some cases yes. Drive past a pirate transmitter and if you are tuned to a nearby frequency there is every likelihood that you will hear the pirate 'splattering' over the top of the station you were trying to listen to (though the same thing would also happen if you drove past a legal transmitter). However, some pirates operate 200 kHz or less away from legal stations which is insufficient to prevent such interference (legal stations typically leave a gap of 400 kHz to prevent these problems occuring). However legal stations typically use much more power than pirate stations and the effect is very localised (and anyway whose to say that your favourite programme isn't on a pirate station...)

londonIt is only in desperation, however, that pirates would choose a frequency likely to interfere with a legal station. In London such desparation stems from the lack of available frequencies (as most are already used by legal and other pirate stations). Given the option, most pirates choose a frequency as unlikely as possible to interfere with legal stations as it's much more likely that a complaint will be received against them if they do cause interference as if they don't.

Overall I suspect that pirate radio does cause interference in one or two cases, however in many cases it operates quite happily without causing problems to anyone else. Kudos to Ofcom for having a go at the problem, but only time will tell whether they will make any dent on the runaway train of stations that inhabit every nook and cranny of the FM band in London (and in some other major cities).

Of course there are other solutions, one being to actually licence the stations concerned and bring them into a controlled environment. Ofcom has already licensed about 30 community radio stations, however it claims that such services can only be licensed in remote areas where spare frequencies exist. A change in planning rules to recognise the low potential for interference that properly organised low-power FM stations cause might open up the band to more users and solve the pirate problem in a much more effective way.
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