Ofcom FM Frequency Availability


We’ve had LOADS of enquiries about FM frequency availability – it seems Ofcom want to “outsource” this activity whilst retaining the cards to make a final decision, and without informing consultants like us who could help.

We are sympathetic to the cause of new “challenger “broadcasters, but without the resources available to a big Government machine like Ofcom, it can seem difficult for stations to engage with them in a constructive way.

We believe the best way is to look at the situation through the “Ofcom periscope” and see the likelihood or not of a given request being viable according to their rules. BUT it’s difficult to give an honest, solid opinion because in addition to Ofcom’s tight technical restrictions (which we can model), they also have to apply judgement decisions – for example is a given interference area significant in terms of size or location? Also as a regulator they have to balance conflicting demand between (say) a Heart FM relay and a new local radio service for your area. We know where the balance should lie, but they have other external pressures!

We now think we may have developed a commercially-viable solution that strikes the right balance to estimate FM frequency availability in an area. We base our judgements upon the latest (current) Ofcom technical rules that they use. Some people may suggest that you to adopt alternative rules (like field measurements) to argue against Ofcom (good luck persuading a Government Quango to do that!). But if you want an honest, balanced judgement on frequency availability (using their rules) in your area, from the Ofcom perspective, then we can help.

FM Frequency Scan

What we CAN do:
– Analyse every FM frequency in your area and estimate incoming interference from every licensed transmitter in the UK
– Rule-out lots of frequencies that are blatantly illegal according to Ofcom rules (including many that may be non-intuitive that would not be obvious from on-site measurements)
– Identify the “most likely” or “least worst” available frequencies in your area
– Give an experience-based, plain English opinion on the viability of your chances, including modifications to your transmitter characteristics that may help in your application. “(eg: “No Chance mate”, “Difficult”, “Maybe”, “What’s the problem” “No problem” etc!)
– If you want to go to the next stage, we can offer a detailed analysis of a particular situation to challenge Ofcom on a particular decision. (This involves a LOT of work, so to reduce the risk of a negative result, we would advise you before starting if there were no chance)

What we CANNOT Do
– Any guarantee that a frequency we suggest is suitable is actually acceptable to Ofcom. They seem to apply additional criteria that we, (and you) do not know about

Some more detail available here.


Here is the News – A Review of Radio News Providers


Here is the news

Coming to you every hour on the hour
Here is the news
The weather’s fine but there may be a meteor shower

No prizes for recognising that 1981 song from Electric Light Orchestra!   But if you are a community, internet or small radio broadcaster, what are your options for a reliable news bulletin at the top of each hour?   In this blog we review the pros and cons of three services, and give our independent recommendations.

The three services we review below are:

  1. IRN/Sky – Well known provider that has been providing news bulletins since the start of UK commercial radio back in 1973
  2. FSN – Feature Story News – London and Washington-based organisation that produces affordable international news bulletins
  3. Radio News Hub – UK-based team of journalists producing updates around the clock for radio stations.

For each news service we assess the aspects that we think are most important for any UK-based station:-

  • Quality – relevance to UK audience, presentation, updates etc
  • Delivery – the ease and flexibility, or not, of delivery methods
  • Cost – there is a surprising variation!

IRN / Sky News

Perhaps the most well known radio news service, IRN/Sky deliver a ready to air hourly bulletin 24/7. The service also includes regular audio and scripts on entertainment news, finance,
technology and sport, including match reporting rights on the Premier League.


Quality is generally good – plus exclusively UK voices as far as we have heard.  However we hear regular complaints that their timeliness is not great – sometimes a second or two early or late starting, or finishing!


The main delivery method is live satellite feed.  There are two alternatives:-

  1. Astra 2A – receivable on a normal 50cm Sky dish (in most of UK) and Sky box.  The audio is delayed by 2 ½ seconds
  2. Astra 4A – needs a larger 90cm dish in UK (which is more tricky to align correctly) but you could still use connect it to a standard Sky box.  Delayed by only ¾  second.

Both satellite feeds can be received on a standard Sky receiver (very cheap on Ebay) but you need to tune it in using the “secret” installer menu.  Also be aware that unless you have battery backup, when the power fails your standard Skybox will no longer relay IRN until you re-select it in the menus!

From experience we know that inexperienced presenters have difficulty in “hitting” the news on time with a live feed.  This is exacerbated because the IRN feed plays other audio almost up to the hour – so they cannot open the fader too early!

IRN do provide a ftp downloadable version of the previous hour’s bulletin.  It is easy to automate download of this file every hour, however it contains the time check from the previous hour!


The cost of IRN depends upon what type of station you are. The price for an online station is £2000 plus VAT per year. If however you are a charity or Community Interest Company then there is a nominal charge of £293.17 plus VAT per year. Rather strangely, Rajar stations (only) can take their Newslink package free of charge, which includes an advert after the end of the news – this is not open to stations who are not on Rajar.


FSN – Feature Story News

Founded in 1992 by journalist Simon Marks, FSN covers news and events as they occur via a network of bureaus in global news capitals across the Americas, Europe and Africa.


FSN offer a choice of 30 second, 3 Minute and 5 Minute world news updates.   Quality is quite good, although in our experience, on average we have found it to be slightly biased towards a more American audience.  Some of the news presenters have American accents, some British.   At weekends, although delivered hourly, it does not seem to change much, so by Sunday evening it can sometimes sound a bit “stale”.


FSN news is delivered hourly online.  It is relatively easy to automatically download the audio files using wget, or a less geeky program as you prefer.   We found that used unedited, the news did not sound “tight” enough due to variable gaps at the start and end of the audio.  This is quite easily fixed by using some software called mp3splt which can automatically top and tail the audio based upon your preferred silence threshold.


FSN’s news bulletins are prices at $15 per month – for that you can choose which one you broadcast, and have rights for on-air and online.

Radio News Hub

Launched in 2015 as a competitor to IRN, Radio News Hub provide news, sport, business and showbiz bulletins to client stations around the UK and around the World 24×7.

Radio News Hub provide an English speaking service from a team based in Leeds.  The on air team consists of Jamie Fletcher (ex Real Radio & Sky Sports News Radio), Stephanie Otty (ex The Pulse & Sky Sports News Radio) and Jon Francis (ex Teamtalk & Sky Sports News Radio).


The bulletin is delivered hourly as a 192kbps mp3 file, which is generally good enough quality for voice.  The quality of delivery is very good, with English voices.   The news bulletin is 1 minute long followed by a 30 second advert.  There are options available for stations that do not want to have the advert and/or community stations that cannot take adverts.


Delivery uses Shared Dropbox folder, which in our experience is the nicest, easiest way to receive such content.  The Dropbox folder will sit locally on your computer and will sync automatically at ten to each hour. Most playout systems can be configured to pick up the news.mp3 file each hour from the same folder.  The sample provided to us did not contain undue silence at start or end, so would not need the topping and tailing stage mentioned above.


The Radio News Hub service costs from £14.99 per month for a one-minute bulletin which contains a 30-second ad.  For that price you also get 10-second national weather + one minute of sport, business and showbiz twice daily Mon-Fri.  So all in all quite good value for around 20 hours of quality audio a month.   Extra premium services are available such as Weekend Sport £5.99 per month, Extended 30 second weather £5.99 per month and International News Bulletins for £49.99 per month


The best choice of news provider will depend upon where your priorities lie.  On one hand, you could say IRN – although it’s expensive, a bit like IBM or Ford, you won’t get sacked for making that choice – they have a proven track record.  On the other hand cost may be king and you’ll select FSN – but remember as in most things in life you get what you pay for!   Radio News Hub looks like it might have hit the optimum compromise for a news service.

Radio News Comparison

Quality – WINNER – Radio News Hub

– IRN and Radio News Hub lead the pack with entirely British voices, best suited for a British audience.  If we had to choose one, we’d select Radio News Hub because being file-based it can be delivered when needed, rather than with a variable delay around the top of the hour with IRN feeds.

Delivery – WINNER Radio News Hub

– Running a small radio station is hard work, so you want to make things as easy as possible.  Hands-down winner for convenience is Radio News Hub.  They use Dropbox which is an elegant and simple solution.  Definitely much easier than fiddling around with satellite hardware and secret installer menus, and easier than using command-line programs like wget and mp3splt on the FSN files.

Cost – WINNER FSN, Radio News Hub close second

– Unsurprisingly the incumbent IRN is the most expensive at £351 per year (including VAT).  The challenger service provided by Radio News Hub is quite a lot less at £180 per year.  FSN is the cheapest at £145 (exchange rate 10 April) – but obviously with some currency uncertainty.


Finding an FM Frequency



We are often told by Ofcom that “there are no available FM frequencies” in an area. We find this an unfortunate situation which can often seem impossible to address. Yet life is seldom that simple, as with all things in life it depends upon what assumptions we use, and what engineering solutions we consider. Here at ABC we contest that in most situations we can find a technical solution to such an assertion. Although we admit that, in the limit, things may be difficult and such solutions may not always be economically or practically viable. But in most situations we can suggest a realistic solution.  IF the regulator is willing to consider it.

We recommend a three-step approach:

1. Assess frequency availability in general, following Ofcom guidelines
2. Verify clear frequencies locally on a radio in several locations or driving around in the target area
3. Analyse the best frequencies in detail, assessing interference from and to other radio services

Step 2 can be done by anyone, steps 1 and 3 need to be done by a radio engineer with access to the right tools.

The ABC Approach

Here at ABC we have recently developed a method to perform step 1 that is very similar to the approach demonstrated by Ofcom in a meeting a couple of years back.  But we believe it has an important enhancement. We believe there is an inherent weakness with the Ofcom approach, because their initial frequency scan is performed from the local broadcast site. By nature the broadcast site is in an elevated location, so it will tend to exaggerate incoming interference compared to the typical listener location.  Real listeners are normally in a town/city centre, low down and amongst building clutter.  We don’t care if sheep on the hillsides get interference!

The ABC approach considers a realistic location in the centre of the target coverage area. We then consider incoming signals from EVERY licenced FM signal in the UK using the latest Ofcom database.  We also take account of first adjacent, second adjacent and +/- 10.7MHz signals as specified in Ofcom recommendations.  Of course we also consider transmit aerial height, aerial pattern and receiver aerial height.  Oh and we factor-in the (controversial to some) Ofcom/ITU protection ratios.  The result is an understanding of the total interference environment in an area, as opposed to on-site snapshot frequency scans that can only be done in a limited number of locations.

Our Results

Our results are displayed as a chart to aid selection of an appropriate frequency.  When all the rules are factored in,we’re often surprised how many of the 205 possible channels get ruled-out from use.  For example see below example for the city of Gloucester – a relatively “quiet” area for FM spectrum (click to enlarge):

Chart showing FM spectrum utilisation in Gloucester

The red columns are channels that we rule-out by Ofcom’s +/- 10.7MHz rule.   Ideally, for full protection a channel we would have a total signal power less than the lower blue line, although the upper line is acceptable for Community radio according to Ofcom rules.  Using this tool we can show that although the spectrum is fairly busy, there are still several potential frequencies.

The Next Step

If we choose 95.4, we can check the feasibility using ABC’s Frequency Viewer tool here:

Map showing utilisation of 95.4 MHz and adjacent channels

This tool indicates that the closest co-channel interferer is Radio Berkshire, but with only 500w at 25m height.  It also displays potential adjacent channel interferers – in the map above we have clicked on one and see that it is Radio Nottingham from Fishpond Hill with 1kW on 95.5.

The Final Stage

Using this information, combined with local drive-round surveys, the next step would be to perform a detailed interference analysis with the most significant surrounding radio services. This involves modelling the “Source” and “Interferer” transmitter in detail in a coverage modelling tool.  Then we’d calculate for every pixel (normally 9 million) whether or not the required Ofcom protection ratio was met.

This last stage involves significant effort, but it is worth the effort – we’ve successfully used this approach to challenge Ofcom’s preliminary allocation and secure double the power for a station!

ABC have over 25 years experience in this sort of analysis – contact us for more information!


ABC Wins Nationwide FM Contract


Map of Middle EastAssociated Broadcast Consultants are proud to announce that we recently won a contract to deliver a nationwide FM network plan for a major economy in the Middle East.  Our Teir 1 client chose ABC to assess the technical and financial feasibility of utilising their existing sites portfolio to host the network.

Work started at the end of 2015 and was completed today.  The delivered feasibility study provided three alternative deployment plans, with further options on transmitter vendor – Nautel or Broadcast Warehouse.  In addition a complete set of Bill of Materials was provided catering for each category of sites, a Total Network Cost Model, and ABC’s unique interactive online “Coverage Explorer” tool.  This tool permits the customer to explore the planned coverage in detail using the power of Google mapping API’s.  They can compare network plans, and switch individual sites on and off to see how much coverage each provides.  We believe this gives our customers powerful and unique insights into their network plans.

If you think ABC can help with your radio network engineering, then Contact Us!


Is Radio 1 Ten Times Better than Commercial Radio? – FM Spectrum Consumption in the UK


It’s a deliberately provocative title – “Is Radio 1 Ten Times Better than Commercial Radio?”  That is to say, does it deserve to be able to use 11 times the FM spectrum resource per listener than Commercial radio?  We could equally have asked:-

  • Is Radio Cymru fourteen hundred times better than Community radio?”  or
  • “Is BBC Radio 3 twice as good as Classic FM?”

These questions stem from an analysis we have done of the way our FM radio spectrum is consumed in the UK.  All things being equal, then approximately the same amount of this precious resource called “spectrum” should be consumed for each listener.  But as we will see, things are far from equal.

FM Spectrum Profligacy?

We’ve long harboured a suspicion that the BBC consumes an inordinate amount of FM spectrum in the UK.  Particularly for local radio there seem to be numerous examples of excessively high powered transmitters on massive hills with huge masts.   This gives a wonderfully strong and reliable signal, but an unfortunate side-effect is that they effectively sterilise that frequency over huge areas of the country – preventing it from being re-used for other services – hence the “no frequencies available” response that many new services get from Ofcom.   One such example is Holme Moss, half a kilometre above sea level atop the Pennines.  It broadcasts three “BBC Local” services from a further 168m up its mast at powers of 4000-5600 watts.  It’s rather bizarre sitting in your student flat in Manchester being able to receive a clear stereo signal for Radio Leeds and Radio Sheffield – cities the other side of the Pennines.  What a waste of FM spectrum resources!

Facts & Figures

But maybe this is an isolated example and we have a distorted view?   We need facts and figures to properly look at this.  So we set-about getting some facts and figures – using the latest Ofcom FM database, and the Q12015 RAJAR figures.

To start at the beginning.  There are three key factors that determine how much FM resource any particular station, or group of stations consumes:

  1. How many transmitters are used for the service/s
  2. The power (ie: watts or kilowatts) of those transmitters
  3. The height of the transmitting antennas above the area they are covering

In the UK there are 205 available FM channels for FM services.  The Ofcom database indicates that there are 1918 licensed FM transmitters using those channels – meaning that on average each channel is re-used 9.4 times up and down the country.   In actual fact some channels are re-used more than this, and some substantially less (see our previous analysis).

The power of these transmitters ranges from 0.05 Watts to 125,000 Watts, and they are broadcast from sites ranging from 1 to 1097 metres above sea level with masts from 3 to 305 metres in height.  Each transmitter (presuming it is stereo) uses approximately one quarter of a MHz of radio spectrum.

To compare the FM spectrum consumption of each transmitter, we chose the unit MHz-Watt. That’s not MHz per Watt – its MHz times Watts.  Just like your electricity meter measures your consumption in Watt-Hours.

As an illustration a service that uses three transmitters of 0.5,1 and 2 kWatts to deliver its service consumes (0.5+1+2)x1000/4 = 875MHz-Watts of FM spectrum (the 4 is because each transmitter uses one quarter of a MHz of spectrum to deliver a stereo service)

Note:- We also tried MHz-Watt-Metres but found that although it changed the figures, it did not significantly change the results.  Use of Metres would also have led to difficult questions – should it be the height of the mast, or the height above sea level, or both combined?  In actual fact whichever metres figure was used it did not change the outcome.  

The Results

So analysis of the Ofcom database yields this top-line result of how our UK FM spectrum resources are consumed.  In short BBC consumes 81%, Commercial Radio consumes 18% and Community Radio consumes only 0.06%.

Watt-MHz utilisation of UK FM services

We can split that down and look at some of the detail – it turns out that BBC Local services do not consume nearly so much spectrum as we had imagined (8.9% versus 8.1% for local commercial services).

Watt-MHz utilisation of UK FM services

If we tried an imaginary scenario where all national services vacated the FM band the split would look like this.  Community radio at last starts to become visible, but would still be tiny.

Watt-MHz utilisation of UK FM services

But of course this does not tell the whole story because it does not factor in how many listeners each station has.  Perhaps the Community Radio share of the FM cake is so small because they have so few listeners?  And vice versa for the BBC national stations?   So now we use a new metric to also take into account each station’s Reach (000’s) as declared in the Q1 2015 RAJAR results.  The unit is Watt-MHz/Reach 000’s.

Watt-MHz per 1000 listeners of UK FM radio services

The result you will see is both surprising and unsurprising.  Radio Cymru consumes most FM spectrum per listener (1123 Watt-MHz per 1000 listeners) – but considering the low population density, and difficulty of Welsh terrain, then this does not seem very surprising.   The consumption per listener of Local vs National radio is interesting – no doubt driven by geographic/population targets for national stations that don’t apply for local services?   The stand-out figure has got to be Community Radio though at only 0.8 Watt-MHz per 1000 listeners.  Admittedly it uses the “Other Radio” RAJAR figure which may over-estimate their share – but even if it over estimates their share by 4 times, Community Radio still consumes half the amount of FM spectrum per listener as BBC and Commercial local radio – and as you will see – 1400 times less per listener than Radio Cymru!


Small Scale DAB Demo


If after 8 weeks you are getting impatient waiting for Ofcom to announce a decision on the successful Small Scale DAB applicants, we thought this video of our Small Scale DAB demonstration might distract you for a while!  Don’t forget to hit the [ ] icon bottom right to view it full screen.  Apologies for the slight sibilance – it’s not Roger Shcott narrating – it seems to be an artefact caused by YouTube’s transcoding!


Small Scale DAB Applications are in!


Ofcom logo

…and they’re off!   Ofcom has published all 51 Small Scale DAB trial applications.   Martin Steers has rather usefully plotted them on a map.

Rather strangely, this map indicates there were no applications received from Wales or Northern Ireland – so it seems this will be an exclusively English and Scottish affair! [Edit – since writing we now can see Hollywood FM BFBS on the map in Northern Ireland!]

The vast majority of applications appear to be from radio stations – thus indicating that Small Scale DAB might follow a different model from National, Regional and Local DAB which embedded a clear demarcation between DAB Multiplex providers (Muxco etc) and programme providers.   However it appears there are some potential “mini-Mux-operators” in the mix – including Ringtone.net who are known to be very active in the Open Digital Radio development community.  ODR is the organisation that has developed, and continues to develop the open-source software through which these trials will be delivered.

Ringtone.net small scale DAB trialMore than one of the applicants (eg: Ringtone.net and Seaside Radio) indicate that they already have operational DAB transmission chains.  This suggests a high state of readiness and must surely increase Ofcom’s confidence that they can deliver operational Muxes within the target 12 weeks from licence award.  We know from our own experience building a DAB transmission chain using the ODR tools that it is not so straightforward as FM, but ultimately achievable, and very reliable once completed.

It is heartening to see Radio Caroline in the mix on both of the above applications – it seems certain that Small Scale DAB will deliver much-needed variety to the DAB airwaves – even for old anoraks like us!

It is interesting to see Celador radio in the list of applicants, despite them already being present on existing “big scale DAB”.  Maybe they see this as a negotiating lever with their current Mux providers, or even a serious alternative?   Or perhaps just a pragmatic way to cost-effectively get a DAB presence for all of their stations.

More interesting still is to see UKRD on the list who already operate 3 “big scale DAB” mux’s.   We wonder whether Ofcom will welcome and encourage such interest, or perceive it as a potential blocking move from an incumbent!


Ofcom Small Scale DAB trial – Too Small?


Basic CMYKWith their latest announcement it is now official – the previous Ofcom Low-Cost DAB trial has seamlessly morphed into a “Small-Scale DAB” trial.   This is an important difference that will impact (negatively) on many radio stations’ commercial viability.

The key difference between FM and DAB is the concept of a DAB multiplex – which combines several stations that take a finite (roughly 7 times more, and no less) amount of radio spectrum more than a single stereo FM station – even if only one station is carried.  Put that the other way – in a “small scale” area we need 7 stations to fill the small-scale-DAB multiplex just to break-even with what is technically possible with FM. That’s fine as long as the rules of the DAB game  permit an adequate coverage area to capture 7 stations.  Yet Ofcom are imposing an arbitrary limit of 100w which in many situations is unlikely to encompass 7 commercially-viable radio stations.

Two respondents to their consultation expressed concern at the arbitrary 100w limit set in the document was not congruent with the parallel Ofcom requirement of:

  • 100w maximum effective radiated power
  • no larger than 40% of the local commercial DAB Mux area.

The latter seemed a reasonable compromise to protect the monopoly incumbents (if really necessary?), whilst the former is an arbitrary power limit that does not make sense compared to the second point (ie: the lower the power permitted the more the transmitters required = £cost).

The Ofcom response was “it is not necessarily the case that allowing a higher power will in all cases reduce the number of transmitters needed” – which answers a question which was not asked!  (hint – sometimes a power above 100w will reduce the number of transmitters needed!)

As far as we understand the DAB infrastructure in the UK is currently provided by a monopoly provider (Arqiva) – a company which claims an EBITDA (profit) margin of 51% – substantially higher than traditional regulator targets like mobile phone companies.  Say no more.

The original low-cost DAB concept trialled by Ofcom offered a potential route to break this monopoly and lower the cost of entry for a new tier of broadcasters.    Their offer to supply equipment for the trial is to be applauded.

Yet in parallel we have a trial licence that is likely to seamlessly morph into the permanent licence regime that handcuffs small broadcasters in a similar way to the current Community Radio Licences – Is it impertinent of us to ask why we have such arbitrary power limitations on this wonderful new concept?


DCMS Community Radio Consultation Response – Part 2


Well finally the DCMS have responded!  Up and down the country community radio station managers are celebrating the decision with magnums of Pol Roger champagne, while small commercial stations contemplate the rapid demise of their business…

We jest of course, but you’d be forgiven for believing us if you had read RadioCentre’s comments on Radio Today!

In reality it’s all a bit of a damp squib as we predicted in our post on Monday.   By DCMS’s own admission (in their Impact Assessment) it is actually a “Modest Change”.  You can see for yourself in their document and on other radio news websites.   Community radio currently has a 0.7% share of radio advertising in the UK (source Ofcom Communications Market report 2014). If all CR stations take 100% advantage of the new £15k advertising ability it will increase to around 1.4% – hardly earth shattering.   In reality though many community stations will use the new “disregard figure” to reduce the considerable time and effort they currently spend raising funds through non-radio means.

And it is also likely that community radio’s share of the radio advertising market is actually increasing the market size.  After all, how many big advertisers have you heard on your local community radio station?  The reality is that these small radio stations with 25watt transmitters run by part-time volunteers attract a different tier of advertisers who cannot afford to advertise on commercial stations.

So in effect today’s announcement from the DCMS is preserving the status quo and nudging it slightly in favour of the community stations.  In the Government’s mind there seems to be a clear divide between community radio and commercial radio, so they have sought to preserve the regulations that ensure no blurring of the lines.

There are a couple of interesting points buried on page 12 of the DCMS impact analysis:-

  1. Community stations will have to request (and pay to apply) to use the new DCMS rules: “where stations will want to take advantage of new conditions a small cost would be incurred by a station to meet Ofcom’s administrative and resource costs – to cover application form, guidance note, assessment and decision”
  2. Perhaps if community stations maintain the pressure there is scope to review the £15k “income disregard” limit over time without waiting for slow legislation: “the income disregard figure will fall to Ofcom to review, on an annual basis, to ensure it retains its worth and benefit to the community radio sector. It should be noted it will be possible for the income disregard figure to be adjusted either up down or to remain unchanged”

We wonder what the radio landscape could have looked like if the DCMS had recommended Option 4 in their Impact Assessment (and learned how to spell!) “4. Full deregulation – Not considered as it would turn community radio into commercial radio undermining wider policy goals. Option 2 is the prefered option.”   A renaissance in local commercial radio could be just the tonic that Radio in the UK needs!

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