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The 'AM death watch' thread...


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Old 29-04-2015, 20:46
Mike_1101
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There may be a niche for lower power AM stations, tightly focussed on local travel to/from work audiences? It's nearly the reverse of the DAB situation; AM can't be pronounced dead until it's not on car radio dials.
Or maybe even small transmitters of a few watts for people who want to create their own AM signals if they have an old radio. Some of the earliest cordless phones went quite a long way, I heard some from over a mile away but nothing remotely interesting.

Why not? medium wave isn't much use for anything else.
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Old 29-04-2015, 21:56
Beacon Hill
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Or maybe even small transmitters of a few watts for people who want to create their own AM signals if they have an old radio. Some of the earliest cordless phones went quite a long way, I heard some from over a mile away but nothing remotely interesting.

Why not? medium wave isn't much use for anything else.
You mean something similar to the 'part 15' stations in the USA & Canada? 0.1 watt on am, good for a mile or so outdoor reception & no broadcast licence required.
Brilliant idea, but existing community stations would poo poo it straight away.
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Old 29-04-2015, 22:23
Mike_1101
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You mean something similar to the 'part 15' stations in the USA & Canada? 0.1 watt on am, good for a mile or so outdoor reception & no broadcast licence required.
Brilliant idea, but existing community stations would poo poo it straight away.
Yes, something along those lines maybe with more power, maximum of 5 watts perhaps?

How many licensed community stations will want to stay on AM when large chunks of the FM band become available?

As the medium wave band is emptying maybe it is time to start thinking about a new frequency plan
531 - 1197khz - existing higher power stations wishing to continue on AM
1206 - 1395khz - local and community stations wanting to continue on AM.
1404 - 1602khz - the low power devices I described.

Obviously there would have to be minimum technical standards and some rules regarding content.
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Old 30-04-2015, 05:34
hanssolo
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1206 - 1395khz - local and community stations wanting to continue on AM.
1404 - 1602khz - the low power devices I described.
Whilst the higher frequencies are best suited to community radio and LPAM licences as the mast can be less high than using the lower frequencies (and even then 3 London stations handed back AM community licences as they could not find suitable sites) in the past some of these AM frequencies were used in a unique way for evening and night skywave transmission to other countries,
I've just taken a look at the AM listings on the excellent 'Frequency Finder' website, which have just been updated

http://www.frequencyfinder.org.uk/AM_Stations.pdf

Look at how many gaps have opened up since some of the European flamethrowers closed down.
but checking 1440 Luxembourg is no longer used for CRI English (now 558 ground wave London), Voice of Russia 1323 from East Germany (now silent other than Smooth in Brighton and VoR programming is now Sputnik on DAB), 1395 was Bigl now silent, 1467 Monaco (France) was TWR English all evening, but now Arabic.
http://www.twr.org/site_schedule/?site=France
1296 was AM and DRM from Norfolk into Netherlands, Germany and Poland now silent
The only station now left using AM Skywave into UK seems to be Seagull from the Netherlands
http://www.radioseagull.com
Radio Seagull can be heard on 1602 KHz AM in the Netherlands, across the North Sea and along the East Coast of England. At night the signal has been received as far away as Finland, Germany and Switzerland.
But low power and shared with BBC Kent (maybe closing soon?) and West London Desi radio which prevents skywave reception of Seagull in these areas.
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Old 30-04-2015, 11:40
Vectorsum
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Or maybe even small transmitters of a few watts for people who want to create their own AM signals if they have an old radio....Why not? medium wave isn't much use for anything else.
By low power I meant 30-300 Watts EMRP, not the 3-30 Watts bracket of the LPAM or 0.3-3 Watts of the highly local hobby AM broadcasters.

The advantage of around 300W EMRP is that you can run it and a studio with battery backup from a fairly modest 5 to 10kW wind turbine or PV array (assuming around 10% TX efficiency from a 15m or so mast), thus taking cost of energy concerns out of the equation after an initial investment. Lots of bodies make grants of up to 50% available for that type of CAPEX.

The existing FM community licences envisage a coverage area of around 5km radius around the TX site, but with the 'Caroline' licences coming up, Ofcom have signalled a much larger acceptable radius without actually fleshing this out; I'm assuming 20km/12 mile radius.

Over half of the population outside London have a commute less than 15 minutes; travelling by car, this could easily take you out of the coverage area of your local FM community station, but you'd likely still be in coverage from your community AM station.
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Old 30-04-2015, 15:07
MikeBr
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Bayerischer Rundfunk is closing its remaining medium wave transmitters on September 30. The two higher-powered transmitters (Munich 100 kW, Nürnberg 20 kW) are on 801. The two smaller transmitters (Würzburg and Hof, both in the northern part of Bavaria) are on 729.
http://www.br.de/unternehmen/inhalt/...radio-100.html
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Old 30-04-2015, 19:21
jimbo
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I think you will find that the big move happened in November 1978 wrt BBC changes. It also happened throughout Europe although one or two networks didn't change setting up some interesting heterodyne whistles as dusk approached.
Radio 3 left 1546 kHz (194m) in 1972. That was to make way for indepe3ndent local radio.

The big changes happened in 1978 on November 23 but there were other changes in December 1972.
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Old 01-05-2015, 00:25
Ex Pat
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By low power I meant 30-300 Watts EMRP, not the 3-30 Watts bracket of the LPAM or 0.3-3 Watts of the highly local hobby AM broadcasters.

The advantage of around 300W EMRP is that you can run it and a studio with battery backup from a fairly modest 5 to 10kW wind turbine or PV array (assuming around 10% TX efficiency from a 15m or so mast), thus taking cost of energy concerns out of the equation after an initial investment. Lots of bodies make grants of up to 50% available for that type of CAPEX.

The existing FM community licences envisage a coverage area of around 5km radius around the TX site, but with the 'Caroline' licences coming up, Ofcom have signalled a much larger acceptable radius without actually fleshing this out; I'm assuming 20km/12 mile radius.

Over half of the population outside London have a commute less than 15 minutes; travelling by car, this could easily take you out of the coverage area of your local FM community station, but you'd likely still be in coverage from your community AM station.
To run 300 watts erp with the mast you suggest would require a TX of a couple of KW. I'm not sure that a battery backup would fit the bill.
Using wind/solar power would still require a connection to the grid and the cost would take many years to recoup. Nice idea but not necessarily the best option.

For a 12 mile radius, i would expect an effective power level of no more than 100 watts (open country) would suffice, depending on frequency.
I ran a 1000 watt TX into a 50 foot antenna (middle of the MW band so efficiency was low) and coverage that met Ofcoms ideal level of local coverage, about 2 mV, was limited to about 12 or 13 miles. Of course it travelled for miles further.
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Old 01-05-2015, 18:30
MikeBr
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Westdeutscher Rundfunk have said that the transmitters at Langenberg 720 85kw and Bonn 774 5kw will be switched off early July.
https://www.infosat.de/radio/auch-wd...ittelwelle-ein
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Old 01-05-2015, 18:46
Mike_1101
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By low power I meant 30-300 Watts EMRP, not the 3-30 Watts bracket of the LPAM or 0.3-3 Watts of the highly local hobby AM broadcasters.

The advantage of around 300W EMRP is that you can run it and a studio with battery backup from a fairly modest 5 to 10kW wind turbine or PV array (assuming around 10% TX efficiency from a 15m or so mast), thus taking cost of energy concerns out of the equation after an initial investment. Lots of bodies make grants of up to 50% available for that type of CAPEX.

The existing FM community licences envisage a coverage area of around 5km radius around the TX site, but with the 'Caroline' licences coming up, Ofcom have signalled a much larger acceptable radius without actually fleshing this out; I'm assuming 20km/12 mile radius.

Over half of the population outside London have a commute less than 15 minutes; travelling by car, this could easily take you out of the coverage area of your local FM community station, but you'd likely still be in coverage from your community AM station.
That would be a good idea in poor countries with unreliable electricity supplies. I can't believe mains electricity costs are more than a 1 or 2% of the operating costs of any british local station.

Do community stations have to pay business rates, or is there an exemption?
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Old 02-05-2015, 11:49
MikeBr
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France Info Nice 1557 will close August 31st, the date when the contract with the operator expires.
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Old 02-05-2015, 12:07
swb1964
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1404 - 1602khz - the low power devices I described.

Obviously there would have to be minimum technical standards and some rules regarding content.
Yes, my only concern would be 'who is going to enforce those rules'? It's not an insoluble problem, but I can see it making OFCOM very busy, especially in cities like London and maybe Manchester/Brum. Who is going to pay for that?
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Old 02-05-2015, 14:16
hanssolo
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By low power I meant 30-300 Watts EMRP, not the 3-30 Watts bracket of the LPAM or 0.3-3 Watts of the highly local hobby AM broadcasters.

The advantage of around 300W EMRP is that you can run it and a studio with battery backup from a fairly modest 5 to 10kW wind turbine or PV array (assuming around 10% TX efficiency from a 15m or so mast), thus taking cost of energy concerns out of the equation after an initial investment. Lots of bodies make grants of up to 50% available for that type of CAPEX.

The existing FM community licences envisage a coverage area of around 5km radius around the TX site, but with the 'Caroline' licences coming up, Ofcom have signalled a much larger acceptable radius without actually fleshing this out; I'm assuming 20km/12 mile radius.

Over half of the population outside London have a commute less than 15 minutes; travelling by car, this could easily take you out of the coverage area of your local FM community station, but you'd likely still be in coverage from your community AM station.
But in London there are possibly only 5 sites (such as Bow, Southall, Heathrow, Lea Bridge and Crystal Palace) that could house a suitable AM mast, From the first community radio round only one AM station Desi is still on air, Last community round 2 in 2010 there were 33 applications http://radiotoday.co.uk/round2/
and only one (Betar-Bangla) of the 4 AM licences awarded made it on air.

There were 6 applications for 972/963 in London so it is possible some of the bid loosers (4 Asian and one Business (Share)) might apply for an AM licence next community round in 2015 sharing an existing AM site, but a new AM site in London may be costly and impractical, whereas finding mast space for a FM or DAB aerial and interference free reception on sets (even online) is more straight forward.
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Old 02-05-2015, 18:48
Colin_London
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France Info Nice 1557 will close August 31st, the date when the contract with the operator expires.
They have different contract dates for different transmitters?!
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Old 02-05-2015, 20:06
Mike_1101
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Yes, my only concern would be 'who is going to enforce those rules'? It's not an insoluble problem, but I can see it making OFCOM very busy, especially in cities like London and maybe Manchester/Brum. Who is going to pay for that?
My guess is that in 5 years time there will be very, very few listeners to AM and it won't really matter. I was thinking in terms of people using the devices to relay DAB, FM or the internet for their own radios and any listeners nearby. I don't think many would bother producing their "own programmes" as the potential audience would be so small.

If anyone started being really stupid and transmitting inflammatory or obscene material, OFCOM could confiscate the device. I think the main users of these devices would be older people, people under 40 probably regard AM as something out of a museum.
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Old 03-05-2015, 11:30
anthony david
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I think the main users of these devices would be older people, people under 40 probably regard AM as something out of a museum.
Sorry to disappoint you but your view on "older people" is out of date by more than a decade, possibly from watching too many soaps on TV or reading "red top" newspapers. Speaking as an "oldie", we use FM and DAB but seldom AM except in the car for 5 Live as it doesn't have DAB. As you get older your hearing dulls and the better quality of FM and DAB helps considerably.

Your Idea of home AM modulators would be abused instantly, even a very low power one would go a long way if connected to a simple long wire aerial to the end of a typical garden. I suspect you would like to do this, probably thinking your choice of music should be heard. Sorry but your choice is no more interesting than my choice to our respective neighbours. In this era of cheap DAB radios why on earth would anyone want to transmit their sound to an AM one. AM radio collectors could connect an extremely low power one (milliwatts) directly to them if they wanted to as long as they didn't radiate.
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Old 03-05-2015, 11:36
lundavra
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Sorry to disappoint you but your view on "older people" is out of date by more than a decade, possibly from watching too many soaps on TV or reading "red top" newspapers. Speaking as an "oldie", we use FM and DAB but seldom AM except in the car for 5 Live as it doesn't have DAB. As you get older your hearing dulls and the better quality of FM and DAB helps considerably.

Your Idea of home AM modulators would be abused instantly, even a very low power one would go a long way if connected to a simple long wire aerial to the end of a typical garden. I suspect you would like to do this, probably thinking your choice of music should be heard. Sorry but your choice is no more interesting than my choice to our respective neighbours. In this era of cheap DAB radios why on earth would anyone want to transmit their sound to an AM one. AM radio collectors could connect an extremely low power one (milliwatts) directly to them if they wanted to as long as they didn't radiate.
And the idea that 300 watts is 'low power' is ridiculous, give free access to that with no restrictions then people would be buying cheap amplifiers online to increase the power. There would end up a war to outdo others as has happened in other countries and with most of them having no technical knowledge there would lots of interference problems.
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Old 03-05-2015, 11:43
Vectorsum
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That would be a good idea in poor countries with unreliable electricity supplies. I can't believe mains electricity costs are more than a 1 or 2% of the operating costs of any british local station. Do community stations have to pay business rates, or is there an exemption?
A very small mast is likely to be only 5-10% efficient depending on assigned frequency in the MW band. Drive that with a 60% efficient TX to get 100W out and you have annual electricity costs in excess of £3000. A 2.5kW micro-generation turbine costs about £10k.

A quick AltaVista using search terms "community radio" and "business rates" brought forth the following as the first hit, from the Community Radio Toolkit
Charitable company

The main advantages of registering your not-for-profit company as a charity are financial and include:

Tax, VAT and rates relief. Charities are exempt from corporation tax, get an automatic 80% discount on their business rates and don’t pay VAT on certain supplies;
...
although I suspect much would depend on whether the premises where you set up have a history of organisations there previously paying UBR.

But in London there are possibly only 5 sites (such as Bow, Southall, Heathrow, Lea Bridge and Crystal Palace) that could house a suitable AM mast....a new AM site in London may be costly and impractical, whereas finding mast space for a FM or DAB aerial and interference free reception on sets (even online) is more straight forward.
Fair point, if you have an abundance of high-rise buildings and third party masts then it's much easier to plonk a Band II folded dipole on one of these and a similar antenna for Band III small-scale DAB is even easier.

However, to give the Highlands and Hebrides as an example, the only games in town are Wireless Infrastructure and Arqiva. The former won't talk to community organisations and the latter want to build you a nice new cabin outside their existing radio room/cabin, saddling you with £15k in costs before you've purchased anything else. AM self-build solutions start to look attractive in those circumstances.

My guess is that in 5 years time there will be very, very few listeners to AM and it won't really matter. I was thinking in terms of people using the devices to relay DAB, FM or the internet for their own radios and any listeners nearby...
There are a couple of 10μW 18kHz-wide licence-exempt allocations at 36.7 and 37.1 MHz precisely for this - check out IR2030/26/1. You don't even have to home-brew your own kit, companies like WireFreeAV will supply you with ready-made L/R channel stuff.

Back on topic I'm illustrating that, with the AM band readily available on car radios for the forseeable future, an AM "death watch" really only applies to the big-iron installations of tens to hundreds of kW; with a bit of forward-planning AM should be able to live on in the community radio sphere, especially when the 'Caroline' CR licences are eventually dished out.
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Old 03-05-2015, 11:50
Mike_1101
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Sorry to disappoint you but your view on "older people" is out of date by more than a decade, possibly from watching too many soaps on TV or reading "red top" newspapers. Speaking as an "oldie", we use FM and DAB but seldom AM except in the car for 5 Live as it doesn't have DAB. As you get older your hearing dulls and the better quality of FM and DAB helps considerably.

Your Idea of home AM modulators would be abused instantly, even a very low power one would go a long way if connected to a simple long wire aerial to the end of a typical garden. I suspect you would like to do this, probably thinking your choice of music should be heard. Sorry but your choice is no more interesting than my choice to our respective neighbours. In this era of cheap DAB radios why on earth would anyone want to transmit their sound to an AM one. AM radio collectors could connect an extremely low power one (milliwatts) directly to them if they wanted to as long as they didn't radiate.
No, I am in that age group myself and was referring to people who used AM regularly on a daily basis for many years. People (probably not very many these days) can still use CB radios to transmit, I have not heard any complaints of interference or obscene language for a many years.

Why would it matter if people used very low power transmitters this way. The medium wave band is of no use for anything else.

Yea we do live in an era of "cheap DAB radios". The sound quality is horrible on the cheapest ones.
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Old 03-05-2015, 12:51
anthony david
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No, I am in that age group myself and was referring to people who used AM regularly on a daily basis for many years. People (probably not very many these days) can still use CB radios to transmit, I have not heard any complaints of interference or obscene language for a many years.

Why would it matter if people used very low power transmitters this way. The medium wave band is of no use for anything else.

Yea we do live in an era of "cheap DAB radios". The sound quality is horrible on the cheapest ones.
As lundavra says, low power would soon become high power blasting through on the audio circuits of neighbours equipment. All cheap radios sound horrid but I understand that "tinny sounding" ones can benefit those with severe hearing loss.
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Old 03-05-2015, 13:14
Mike_1101
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As lundavra says, low power would soon become high power blasting through on the audio circuits of neighbours equipment. All cheap radios sound horrid but I understand that "tinny sounding" ones can benefit those with severe hearing loss.
Here is an extreme example for you. A few years ago I was on a continental holiday, took a wrong turning and accidentally ended up at this transmitter site.
Europe 1 Felsberg - http://tvignaud.pagesperso-orange.fr/am/e1/fr-e1.htm
The feeder cables to the aerials actually cross a public road. Meanwhile the FM radio and electrical systems in my car were working perfectly and suffered no damage. This is a 2,000KW transmitter, I doubt if anywhere in the world has a higher signal strength than that.
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Old 03-05-2015, 13:57
Glenn A
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Why scrap AM, there's no room on FM for the three networks that use it, and also DAB isn't universal and most cars only have AM/FM radios? I'm sure someone listening to a football match isn't that bothered about hearing it in stereo and a lot of the oldies played on stations like Classic Gold are in mono anyway.
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Old 03-05-2015, 14:49
Colin_London
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Here is an extreme example for you. A few years ago I was on a continental holiday, took a wrong turning and accidentally ended up at this transmitter site.
Europe 1 Felsberg - http://tvignaud.pagesperso-orange.fr/am/e1/fr-e1.htm
The feeder cables to the aerials actually cross a public road. Meanwhile the FM radio and electrical systems in my car were working perfectly and suffered no damage. This is a 2,000KW transmitter, I doubt if anywhere in the world has a higher signal strength than that.
I parked up next to the RMC transmitter in Provence once. After a quick sortie to get photos I couldn't get back into my hire car which used an RF key fob. Had to ease off the keyhole cover to use the manual key to get back in!
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Old 03-05-2015, 14:52
kev
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Why scrap AM, there's no room on FM for the three networks that use it, and also DAB isn't universal and most cars only have AM/FM radios? I'm sure someone listening to a football match isn't that bothered about hearing it in stereo and a lot of the oldies played on stations like Classic Gold are in mono anyway.
The equipment used for the MW networks will be getting towards the end of it's life, and replacing this (or even keeping the old gear running) will cost and increasing amount of money per listener which would be better spent on programming content. In our urban areas the MW signals are getting worse all the time and becoming an increasing irrelevance.

Absolute and talkSPORT already have greater coverage on DAB than they do on MW*, and it wouldn't surprise me if Five Live falls into that boat too.

In all three cases listeners to each of those stations are also missing out on programming that is/will-only broadcast on there secondary stations. In addition once these stations become digital only the broadcasters will have more scope to shuffle programmes round to minimise interruptions to broadcasts.

The BBC are looking at increasing the amount of programming on BBC Radio 5 Live Sports Extra from the start of next year.

talkSPORT will be joined by talkSPORT2, talkRADIO, and talkBUSINESS on DAB around the same time

Absolute Radio has for years had numerous additional services, including live football coverage on DAB only.


* of course this doesn't mean every listener who gets the MW signal gets DAB - there are plenty that get DAB and no MW.
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Old 03-05-2015, 15:01
swb1964
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and a lot of the oldies played on stations like Classic Gold are in mono anyway.
Quite a lot are in stereo, but even the mono ones sound better on DAB , IMHO.
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