Wireless Waffle - A whole spectrum of radio related rubbish
CBGB (Citizens Band Great Britain)signal strength
Friday 11 March, 2016, 13:34 - Radio Randomness
Posted by Administrator
dukesofhazzardWireless Waffle has been contacted by Will Hogan who is putting together a book entitled 'CBGB' which will celebrate the culture of CB radios across Great Britain in the 1980s. To let Will take over the commentary:
Inspired by the amazing artwork of Eyeball cards, we aim to interview enthusiasts to get a real insight from the people that made it happen, and explore the cards themselves.

We already have a bank of cards from Suffolk, and a few interviewees, but we really need more to show the national scope of CB culture at this time. I'll be working with award-winning photographer, David Titlow who specialises in portraits (his work can be seen at the National Gallery as he's the latest recipient of the Taylor Wessing portrait prize).

Absolutely any help we could get - even looking at Eyeball cards that anyone has - would be amazing. There's no pressure to talk or be quoted, but anyone who would be willing to would be fantastically helpful.

If you could help Will out, please get in touch with him. His telephone number is +44 (0) 7966 072826.
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Is the UK overpaying for the digital dividend?signal strength
Monday 29 February, 2016, 08:16 - Broadcasting, Licensed
Posted by Administrator
Some time ago, Wireless Waffle discussed the various bidders to provide the television transmitter network for the UK's fledgling local TV stations. As part of this, the company responsible for providing the transmitters and masts for all of the other UK digital terrestrial television stations, tax evading transmitter supremos Arqiva, provided indicative figures for the costs of building the local TV transmitters. Their 'Reference Offer' details, on a site-by-site basis, the costs, as Arqiva saw them, of providing the requisite service together with the cost of providing 'network access' only (e.g. the rental of space on their masts). The figures vary by a factor of about 8 to 1 between different sites. But to what extent are Arqiva beefing up the actual costs to make a profit on their largely monopolistic position?

sheffield tv transmitterMaybe an example would be useful, so let's consider their proposals for the Sheffield transmitter, one of the cheapest in their offer. Their prices are as follows:
  • GBP 147,397 one-off costs, and;
  • an annual fee of GBP 17,783.
The one-off costs include site planning, preparation and installation, antennas, transmitter and multiplexer and the annual fees include rental of the site, a management fee, electricity, rent, light and heating.

According to Ofcom's local TV feasibility study, the technical details for the Sheffield site are:
  • Frequency: Television Channel 55, vertically polarised
  • Transmitter power: 100 Watts e.r.p. requiring a transmitter output power of 28 Watts (taking into account antenna gain and cable loss)
  • Antenna height: 43 metres
  • Antenna type: 2 x log periodic on a bearing of 110 degrees
Let's start with the stuff we have to buy. A 28 Watt DVB-T transmitter costs around GBP 10,000. Antennas can be had for GBP 100 each and we need two. Cable (let's assume 60 metres to allow a few metres at the bottom of the mast to reach the transmitter and a few left spare) of LDF4-50 which gives less than 3dB of loss, is around GBP5 per metre, making a total of GBP 300 for the cable. The mast of the tower is 52 metres high, so let's assume GBP 2500 to make space for the local TV antenna. And to be generous, let's add in another GBP 5000 for sundries such as connections to electricity, rack space and so on. Much of the remaining DTT functions (e.g. multiplexer and encoder) can be done in software, so GBP 2500 for a high-end PC to do some storage, playout, encoding and multiplexing. This makes a total capital spend of GBP 18000. Even accounting for a very healthy profit margin this means that Arqiva are charging well over GBP 100,000 for 'site planning, preparation and installation'. Maybe television engineers are particularly expensive in Sheffield?

working on transmitterAs for the annual costs, let's say it requires a visit every month to check on how it's working and this is one person dedicated for the day (though no doubt they would be checking on all the other transmitters on the site too), at a reasonable estimate of GBP 500 per day, to include the cost of petrol and transport, this equates to GBP 6000 per year. The power required for a 28 Watt transmitter assuming it is 20% efficient, is 140 Watts (equating to 1,227 kWh of electricity per year) which at today's prices would cost around GBP 122 per year. Allowing a further GBP 500 per month towards the maintenance of the buildings, air conditioning, mast and so forth (noting that these will have already been paid for by the existing tennants), the total annual fees would be around GBP 12,122. The annual fee proposed by Arqiva is therefore not as badly over-egged, no doubt the 'management fee' covers a lot of this difference.

So, in conclusion:
  • Arqiva seem to have extensively overpriced the capital work associated with providing and installing the local TV transmitter; but
  • The proposed annual fee seems much more reasonable.
Moving forward to today, the European Commission has just published a report by consultants LS telcom and VVA which, amongst other things, examines the cost of changing the frequency of all the digital television transmitters in Europe to clear the 700 MHz band, whilst at the same time migrating to DVB-T2. The costs detailed in the report, catchily entitled, 'Study on Economic and Social Impact of Repurposing the 700 MHz band for Wireless Broadband Services in the EU', are that to do this mammoth re-engineering task would cost between EUR 456 and EUR 888 million.

The study makes the assumptions that:
  • Existing antennas are broadband and can be re-used;
  • Existing transmitters will be upgraded rather than replaced.
These two assumptions are open to challenge. Whilst most new UHF antennas are broadband and thus in theory would not need changing, there can be instances where antennas have been designed to provide very specific radiation patterns (e.g. to provide nulls in certain directions for co-ordination purposes) and thus a change in frequency would affect their radiation pattern and may require a new antenna. Evidence suggests, however, that the transmitters themselves should be able to be converted from DVB-T to DVB-T2 by only replacing the modulator.

dvb t2 conversion
Source: Assessing the technical requirements and implications of DVB-T transitions

The 'cost per transmitter' given in the report ranges from EUR 20,000 to around EUR 50,000, which seems reasonable given the assumptions made. Arqiva's estimate for re-tuning the UK's transmitter network to clear the 700 MHz band provides values ranging from GBP 310 to GBP 470 million (approximately EUR 400 to EUR 600 million) putting the price for re-farming the 700 MHz band in the UK at approximately the same level as the Commission report identifies for the whole of the EU!

There are approximately 1,200 transmitter sites in the UK, the smaller ones with three multiplexes on them and the larger 90 or so with six, seven or eight, making roughly 4,000 transmitters in the UK. Taking the consultants' report's 'per transmitter' value, the price for re-farming the spectrum in the UK ought to be nearer to EUR 80 to 200 million, a factor of 2 to 8 times removed from the prices quoted by Arqiva, depending on which end of the ranges quoted you take.

So who is right? It seems that the two reports are doing something slightly different:
  • The Commission's report assumes that existing multiplexes and frequencies are converted to DVB-T2 and as such fewer are needed. In only very few cases would there therefore need to be a change in frequency, as the additional capacity of T2 (and MPEG-4) would mean existing frequencies could largely be re-used.
  • The Arqiva report is trying to move all existing multiplexes (whether DVB-T or DVB-T2) to new frequencies, which is (clearly!) a much more expensive undertaking.
arqiva happy moneyPerhaps Ofcom should take a leaf from the Commission's book, and instead of trying to re-engineer the UK's DTT network to be the same, should instead take the opportunity to convert the network to be DVB-T2 only and save a lot of money in the process. Given the timetable for the clearance of the 700 MHz band (e.g. around 2020), and that typical television replacement cycles are 7 years, the average British household would already have a T2 receiver by then... Then again, no doubt Arqiva could find some 'management costs' to soak up any savings!
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Pirate radio to go digitalsignal strength
Saturday 23 January, 2016, 11:49 - Broadcasting, Licensed, Pirate/Clandestine, Radio Randomness, Spectrum Management
Posted by Administrator
The number of pirate radio stations on-air in London does not appear to have diminished over the past 10 or more years, despite there now being many legal ways in which stations could reach their audiences, most recently though streaming audio on-line.

brighton dab transmitterOfcom has recently proposed that many local radio stations could be accommodated on 'small scale DAB' transmitters which provide a localised service, and it is conducting a number of trials around the UK of such a service. The idea is to use low cost hardware and software to develop the DAB signals, for example using a USRP software radio, and the various software tools provided by the Open Digital Radio project. Using these, it is possible to put a (very) low power DAB station on-air for less than GBP1000 and with a suitable power amplifier (for example a 30 Watt Mitsubishi amplifier module, or how's about a 1.2 kW amplifier module), a DAB transmitter with reasonable coverage can be built for not that much more. Indeed research conducted for Ofcom suggests that a 100 Watt e.r.p. service using such technology could be provided to broadcasters for around GBP1400 per year (at a bit rate of 160 kbps which is far higher quality than most of the existing UK DAB services!)

An article in spectrum newsletter PolicyTracker entitled, 'Can DAB save us from the pirates?' (note - a subscription is required to read the full article), makes the point that the criteria which the UK has set to begin the digital switch-over of radio services (e.g. the turning off of analogue services in favour of digital) is almost upon us. The criteria is that 50% of UK listening should be on a digital platform (whether DAB, on-line, cable, satellite or other) and the latest figures show this is now up to 43%, though as Wireless Waffle has pointed out before, the proportion of digital listening appears to have stagnated. If the UK does set a date for the winding down of FM radio, one of two things could happen:
  1. pirates may move to digital platforms, in order to be found on the same dial as other stations; or
  2. pirates may take the opportunity of an emptier FM band to choose clearer frequencies, increase their power, or just increase the number of services.

The problem is that in either case there is no guarantee that the pirates would do this in a legal fashion. Pirate radio stations are not renowned for co-operating with each other so why would they pay to be on a DAB platform, rather than buy the equipment themselves and set up digital pirate stations? The answer might come in the form of the reduced number of frequencies available. In the FM band, assuming a station every 300 kHz (which is just about OK from an interference perspective), there is room for 68 stations on the dial. Taking into account the 20 or so legal stations already on-air in London (depending on what you count as London), this leaves a potential for 48 pirates. For DAB radio, which requires 1.4 MHz of spectrum to operate, there is room for just 32 transmissions in any one location. In London 4 of these frequency blocks are in use, leaving 28 'available'.

local dab radio"Ah", you say, "but each DAB multiplex can carry 10 or more stations, so really the number is 280". That is true, but this requires the pirates to club together to buy and operate the equipment and, as already stated, they aren't that good at this. Perhaps the business model they employ could change, and a smaller number of illegal transmitter operators could provide services to multiple pirate stations. Or perhaps a small number of legal transmitter operators could provide the same service. The problem here seems to be that in order to legitimise the pirates, they would have to be invited to 'come in from the cold', and Ofcom would have to have a set of licensing policies that were sufficiently lax to permit 24 stations all playing the same kind of electro-shed, play-house or garage-door music onto the dial. It is almost certain that the existing legitimate stations would object to this on the grounds that it would provide unfair competition. But the fact is that such competition already exists on the FM band, and at least if it were done under a licensed framework, there would be some control over what went on, and thus greater protection of the existing 'big boys'.

Maybe Ofcom could take a leaf out of the book of the Lebanese regulator (the TRA) who offered all unlicensed FM operators (which was a large proportion of the country's stations at the time), a licence, if they came forward and provided the necessary details of their transmitting facilities (power, frequency, antenna height and so on). Most stations did this, wishing to gain legitimacy for their service. As soon as they did, however, the TRA could begin to change frequencies, powers and so on to bring the stations in-line, through a proper legal framework that allowed them to inflict penalties if people refused.

pirate surrenderAnother model might be for Ofcom to licence small-scale DAB operators, but not to set any criteria over which stations are carried on the multiplex, other than their normal broadcasting code which is designed, for example, to stop politically motivated stations from using the airwaves in an partial way. Other than a bit of swearing here and there, most pirate stations would probably already meet most of the rules. This is not dissimilar to the way in which Ofcom licenses digital television, with multiplexes being awarded to companies who are then largely at liberty to select which programmes they include.

In either of the above cases, whether the idea that Ofcom could have an 'amnesty' for pirates, if they agreed to go onto small DAB multiplexes, or if the operation of the DAB multiplexes were made flexible enough to accommodate pirate stations being on them, there might be a sufficient increase the listening to DAB services such that the necessary 50% switch-over threshold is reached sooner rather than later. A 'win-win' situation?
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Investing in VoIP for cheaper callssignal strength
Monday 28 December, 2015, 17:39 - Equipment Reviews
Posted by Administrator
Making phone calls in the UK has rarely been as cheap as it is today. Most mobile contracts provide almost limitless free UK calls and even low cost pay-as-you-go services such as those provided by GiffGaff offer plenty of bundled call minutes.

However, calling from fixed-lines remains relatively expensive. Though the fixed line operators provide packages with bundles of calls, these are surprisingly costly and without these packages, the call rates are often high. The table below sets out the relative costs of different phone (and broadband) packages from some of the bigger suppliers, based on someone making one hour of phone calls a month (to a fixed line), an hour per week and one hour of phone calls a day (to a fixed line).

OperatorCost per minuteCost per month
Unlimited Package*(60 mins per month)(60 mins per week)(60 mins per day)
Virgin Media10.6p£8.00£6.36£27.56£193.58

* Additional monthly cost for unlimited calls over and above standard package

It is absolutely clear, therefore, that anyone who makes more than cursory use of their fixed line (to call other fixed lines) should be taking the operators' all inclusive packages for calls as the break-even point is arond the one hour of calls per month level (or two minutes per day).

But the situation becomes far more complicated in the case that anyone wishes to make international calls whether from a fixed line or a mobile. International calls are generally far more expensive than domestic fixed line calls and though some operators offer bundles of minutes for some destinations, and even though there are a myriad of calling cards and other methods for reducing the cost of calls, they tend to be complicated to use.

At the Wireless Waffle HQ, calls to UK fixed lines, as well as to international destinations, are a day-to-day requirement and the cost of these calls was becoming significant. At the same time, a method which allows these calls to be made whilst being so user friendly that it was no different to a standard phone was essential to ensure that the rest of the residents of the HQ did not have to dial short-codes or press extra buttons when making a call.

gigasetThe answer came in the form of the Gigaset N300IP DECT base station, teamed with a matching DECT handset (such as the Gigaset A510). This canny device allows a standard fixed-line and a Voice over IP (VoIP) line to be integrated seamlessly. What this means is that incoming calls (on either line) ring the phone as usual, but that outgoing calls go via the VoIP line. VoIP has been around for a long time - it uses the Internet to make phone calls. Years ago, the quality was poor and calls somewhat unreliable but today with a reasonable broadband connection, the quality is excellent and most importantly, the call rates are cheap - very cheap.

https   www miso comms net  miso logoThe VoIP provider used at the WW HQ is Miso Comms. Whilst there are endless VoIP providers available, some of who are even cheaper than Miso for certain calls, the company is run by a team of telecommunications professionals who really know what they are doing. Of course they're out to make a profit just as anyone else, but with such a credible background, the service and prices are both excellent. Most international calls are under 2p per minute and UK fixed line calls are just 0.63p per minute (e.g. 38 pence per hour) and the call quality is far better than many VoIP services that we at WW have tried in the past. What's more, in addition to using their service on the Gigaset unit, it can also be programmed into mobile phones (using the SIP protocol) and an app such as CSipSimple such that these low call rates can also be used from a mobile device connected to, for example WiFi. This means the low cost calls can be made from just about anywhere with a decent internet connection and not just home.

The Gigaset units will set you back around œ70 for the base-station and the handset together which amounts to around a full year's subscription to unlimited calls from the main phone providers. But for international calls, the savings clock up virtually immediately. In most cases, anyone making 60 minutes per month of international calls will pay for the equipment in less than a year and in many cases, much more quickly. If you just put the CSipSimple app on your phone, the savings are instantaneous. If you have family around the world (or around the corner), why not give VoIP a go.
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