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The 'AM death watch' thread...


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Old 09-04-2016, 13:03
Mr_Boltar
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As David says MW does not have the bandwidth for FM or even narrowband FM as it only has 9khz slots.
Of course there's the bandwidth. A 9Khz wide FM signal will give you the same fidelity as an AM signal of the same width - 4.5Khz mono. I wasn't suggesting 15Khz FM stereo as per VHF! My main concern would be late night interference , FM signals don't mix well so you tend to get noise or the receiver flip flopping between signals instead of 2 signals superimposed with a bit of heterodyning as on AM.
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Old 10-04-2016, 15:07
MikeBr
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Interesting R Maria restarting local MW (rather than national) in the Netherlands, must have found a new mast location?
The antenna is on the roof of Heilig Bloed monastry 15km NE of Eindhovenm scroll down to bottom for three photos. Transmitter power 1kw.
http://radioforum.foren.mysnip.de/re...1354757,page=1

It' went on the air 1800 yesterday, weak on the Twente receiver
http://websdr.ewi.utwente.nl:8901/

but you can confirm it by narrowing the bandwidth on Twente and using mute and checking on their webstream which can also be muted.
http://www.radiomaria.nl/wp/player/
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Old 14-04-2016, 10:15
commseng
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I see that a temporary replacement for the 693kHz Radio 5 site at Start Point has appeared on mb21 - West Prawle (thanks Martin Watkins)
http://tx.mb21.co.uk/gallery/gallerypage.php?txid=2145
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Old 14-04-2016, 11:20
martinwatkins
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Well spotted! Made a nice day out...

I'll PM you.
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Old 14-04-2016, 12:57
Vectorsum
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A Datatrak mast, eh? I didn't know any of those were still standing.... OT for the 'AM Deathwatch', but I worked for Securicor in the early nineties, with the PMR tentacle down in Radstock, in what was then Avon.

The techs downstairs who had been trained to service the Datatrak VHF/UHF uplink units would talk now and again about how the 'RF module' was a bare push-pull power FET stage connected pretty much directly to the antenna. The uplink was a time division system over all units using that frequency everywhere in the UK and Ireland, and had such a miniscule duty cycle that neither any ATU nor any heatsinking was required for the RF stage.

I would love to have actually seen one, but none came into the workshop in the year I was around as they were, quite literally, bomb-proof.
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Old 14-04-2016, 15:57
martinwatkins
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Interesting, thank you Vectorsum.
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Old 09-05-2016, 12:13
MikeBr
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Redmoss 990kHz always was a very strange outpost of Gaeldom; that the service vanished without a whimper shows that the "audience" was probably in the low double figures. It didn't even get a mention on the Beeb's own reception advice news. It would actually be quite interesting to know the thought process of whichever Beeb wonk thought it would be a great idea to put RnG onto 990 after Radio Aberdeen's disappearance.
Alan Pennington of the British DX Club sent a FOI request to the BBC about the closure of 990 Radio nan Gaidheal, the answer to which is published in the latest issue of their magazine Communication. IT includes after mentioning the introduction of the Meldrum 104.2 FM channel for RnG in 2003:

"Over time it was believed that listeners would migrate to FM reception. By 2015 it was considered that very few (if any) listeners would still be using 990.

The transmission was closed on a trial basis on 23 November 2015. The trial was intended to confirm the BBC's assertion.

"No announcement was made by the BBC ahead of this trial however to ensure that any relevant responses from the public were shared all relevant departments in the BBC were briefed ahead of the trial including Audience Services, Reception Advice, BBC Scotland Communications and of course Radio Nan Gaidheal.

Over a two month period the BBC received no enquiries from the public regarding the closure. As such the decision was taken to make the cessation final on 29 January 2016."
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Old 09-05-2016, 13:06
Vectorsum
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...Over a two month period the BBC received no enquiries from the public regarding the closure [of Redmoss 990 kHz RnG]. As such the decision was taken to make the cessation final on 29 January 2016.
Even if the Gaels had called to complain, the phrase they would probably have used to indicate that their radio wasn't working: "...Tha an rèidio agam aig a cheann-ùidhe..." literally translates as "my radio has reached the end of its working life". Poetic, in a sense.
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Old 09-05-2016, 13:09
Colin_London
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Alan Pennington of the British DX Club sent a FOI request to the BBC about the closure of 990 Radio nan Gaidheal, the answer to which is published in the latest issue of their magazine Communication. IT includes after mentioning the introduction of the Meldrum 104.2 FM channel for RnG in 2003:

"Over time it was believed that listeners would migrate to FM reception. By 2015 it was considered that very few (if any) listeners would still be using 990.

The transmission was closed on a trial basis on 23 November 2015. The trial was intended to confirm the BBC's assertion.

"No announcement was made by the BBC ahead of this trial however to ensure that any relevant responses from the public were shared all relevant departments in the BBC were briefed ahead of the trial including Audience Services, Reception Advice, BBC Scotland Communications and of course Radio Nan Gaidheal.

Over a two month period the BBC received no enquiries from the public regarding the closure. As such the decision was taken to make the cessation final on 29 January 2016."
The fact that the transmitter was switched off and no-one noticed (except months later through reviewing a transmitter parameter spreadsheet) says it all. Totally justified.

Incidentally why did BDXC think this merited a FOI request (and hence more expense to the BBC?).
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Old 09-05-2016, 13:21
MikeBr
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The fact that the transmitter was switched off and no-one noticed (except months later through reviewing a transmitter parameter spreadsheet) says it all. Totally justified.

Incidentally why did BDXC think this merited a FOI request (and hence more expense to the BBC?).
Because they publish a very useful list of radio stations in the United Kingdom as well as having a monthly UK news column. The BBC had failed to respond to enquiries confirming the closure of RnG, as this had not been publicly announced as closures usually are, or if there were any plans to restart transmissions from Redmoss on 990. The BBC said there were not.
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Old 09-05-2016, 15:23
Orangy
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Quite honestly, where contracts can now be broken out of/expired, the BBC really should be switching BBC LR AM stations off where DAB coverage is now sufficient.

Funding is critically tight for the BBC and AM is a money sucking resource which is just duplication in many cases.

The BBC doesn't like shutting much down, but I can't see it not happening soon - especially as it was part of Delivering Quality First.
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Old 09-05-2016, 15:40
kev
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Quite honestly, where contracts can now be broken out of/expired, the BBC really should be switching BBC LR AM stations off where DAB coverage is now sufficient.

Funding is critically tight for the BBC and AM is a money sucking resource which is just duplication in many cases.

The BBC doesn't like shutting much down, but I can't see it not happening soon - especially as it was part of Delivering Quality First.
The Nottingham one sticks out like a sore thumb - an area without MW except a small relay for years, well covered by FM and even better covered by DAB yet still hanging on in there, in a multiplex area where > 50% of listening is digital
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Old 09-05-2016, 15:47
Tony Richards
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Still a lot of BBC Locals on AM. Are they really needed? We seem obsessed with putting radio stations on as many platforms as possible. To save money the BBC should close all AM transmitters that have FM equivalents then think about really promoting DAB for what is left on AM. If the ultimate aim of putting services on DAB, satellite, Freeview and of course, on line, is to move to digital only how long before anything significant happens?
The experience of closing RnG on AM (a unique language station in areas where there isn't a mass of alternative listening) seems to prove that changes can be made.
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Old 09-05-2016, 16:28
Gerry1
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MW coverage can have its uses during special events. For example, a weekend or two ago BBC Essex covered three football matches simultaneously, one on each of their three MW frequencies.

However, I must admit I'm surprised that stations such as BBC Essex don't make better use of DAB/DAB+ for split programming. They could have three matches at 32kbit/s DAB+ while keeping the faith by simulcasting the normal programming on FM stereo and 32kbit/s DAB+ stereo.

Alternatively if they really fear a flood of complaints from a handful of listeners with only a Pure Evoke-1, they could split it as football 3 x 24kbit/s DAB+ plus normal programming on 56kbit/s DAB mono.

Either way, they could save money by closing the MW outlets without cutting any services.
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Old 09-05-2016, 17:37
hanssolo
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The BBC doesn't like shutting much down, but I can't see it not happening soon - especially as it was part of Delivering Quality First.
The first report seemed to say shutting down R4 LW and local English MW could be straightforward with MW staying in some areas like Derbyshire, Cumbria and Gloucestershire, but the final report showed more caution.
http://downloads.bbc.co.uk/bbctrust/...onclusions.pdf
Not re-invest in Long Wave technology once the current infrastructure, which relies on technology that is no longer being manufactured, has reached the end of its life. Although this is unlikely to happen for several years, we welcome the Executive‟s commitment to make the existing programmes provided on LW available on other analogue BBC radio stations, so remaining as accessible to
listeners as they are now

We also agree with the principle to try and reduce medium wave transmission for local radio in places where coverage duplicates that of FM. However, establishing the audience impact of these changes is not straightforward, and the Executive needs to undertake further technical and feasibility work to establish the costs and impact of these changes within each part of the country. We will engage further with the Executive on this issue over the coming months before any final decisions are taken.
Agree now Redmoss and Bristol AM have closed might see more AM closures.
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Old 09-05-2016, 18:51
Orangy
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The first report seemed to say shutting down R4 LW and local English MW could be straightforward with MW staying in some areas like Derbyshire, Cumbria and Gloucestershire, but the final report showed more caution.
http://downloads.bbc.co.uk/bbctrust/...onclusions.pdf

Agree now Redmoss and Bristol AM have closed might see more AM closures.
Think how much money the BBC could have saved had they implemented this 3-4 years ago. The local DAB rollout could potentially (had it not been for the wrangling over who pays for what) have been funded sooner.

Still, if Whittingdale and his cronies gets their way by systematically destroying PSB in the UK - BBC and C4, then we won't have to worry at all!
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Old 09-05-2016, 19:04
buglawton
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Of course there's the bandwidth. A 9Khz wide FM signal will give you the same fidelity as an AM signal of the same width - 4.5Khz mono. I wasn't suggesting 15Khz FM stereo as per VHF! My main concern would be late night interference , FM signals don't mix well so you tend to get noise or the receiver flip flopping between signals instead of 2 signals superimposed with a bit of heterodyning as on AM.
Just happened to be listening to BBC World Service on my DAB at home, this makes me one of 150m worldwide apparently. They remind people of the various relays you can listen on, just now it was the Berlin FM one so that's not going away anytime soon.

Then I recalled when I lived in Brussels in the late 70s. BBC WS was on 648 and in the centre of Brussels perfect loud & clear both day & night, no fading, interference or co-channel. As if it was being broadcast from just outside of Brussels. 648 also covered whole of Holland. Now most car radios in the Benelux still have AM. I think it was a folly to turn off 648 KHz considering it's effectiveness. Perhaps if the BBC had kept it, those Eurocrats would've been making better decisions and we wouldn't all be so Eurosceptic now!
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Old 09-05-2016, 19:46
hanssolo
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[quote=buglawton;82351304
Then I recalled when I lived in Brussels in the late 70s. BBC WS was on 648 and in the centre of Brussels perfect loud & clear both day & night, no fading, interference or co-channel.[/QUOTE]
The target is now mostly Africa and Asia so sadly the expensive Orfordness MW site went. It can still be heard on satellite, cable and internet in Europe, plus DAB+ in Brussels and via WRP Paris.
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Old 09-05-2016, 20:29
swb1964
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Was 1296 audible on the continent as well?
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Old 10-05-2016, 08:54
buglawton
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1296 was targeted at aster Europe using night propagation. Hopped over Western end of Europe so not much use for Benelux.
648 should should down in history as the most cost-effective (cost PER LISTENER) and strategic relay ever, bearing in mind how it covered Brussels. I wonder if it was audible in Strasbourg.
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Old 10-05-2016, 09:10
Vectorsum
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...648 should should down in history as the most cost-effective...and strategic relay ever, bearing in mind how it covered Brussels. I wonder if it was audible in Strasbourg.
648 kHz was perfectly audible at about S3.5 to the southwest of Stuttgart, and was my travel-to/from-work listen for two years. Strasbourg is pretty much on the same bearing r.t. Orfordness and a smidge closer so would have gotten the same or better. AFAICR it wasn't the standard WS programming but a special European service.
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Old 10-05-2016, 09:38
MikeBr
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1296 was targeted at aster Europe using night propagation. Hopped over Western end of Europe so not much use for Benelux.
648 should should down in history as the most cost-effective (cost PER LISTENER) and strategic relay ever, bearing in mind how it covered Brussels. I wonder if it was audible in Strasbourg.
The BBC schedule in the 1994 handbook gives the target area of 1296 as Central Europe with as well as some English services in Czech, German, Hungarian, Polish, Slovak, Slovene and Turkish, presumably for Turks in Germany. Didn't use it for Bulgarian or Romanian.

Dutch station Radio Nationaal and Radio Netherlands have also used 1296. Radio Caroline also used it on 19 August 2000 for a Caroline supporters day in Leeuwarden.
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Old 10-05-2016, 09:50
Gerry1
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648 kHz was perfectly audible at about S3.5 to the southwest of Stuttgart, and was my travel-to/from-work listen for two years. Strasbourg is pretty much on the same bearing r.t. Orfordness and a smidge closer so would have gotten the same or better. AFAICR it wasn't the standard WS programming but a special European service.
With Project Fear now in mega-overdrive warning us that if we leave the EU there will be plagues of locusts and the world will stop turning, it seems very odd that we've already decided that Nation Shall No Longer Speak Unto Nation !
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Old 10-05-2016, 10:01
MikeBr
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With Project Fear now in mega-overdrive warning us that if we leave the EU there will be plagues of locusts and the world will stop turning, it seems very odd that we've already decided that Nation Shall No Longer Speak Unto Nation !
Except we haven't as the world has moved on since the 1950's, BBC World Service is part of a multiplatform service including television, the internet, local FM relays etc and has a record audience. Medium wave stations are closing down all over Europe hence the title of this thread and since the Cold War Europe has never been a particular target area of BBC WS anyway.

http://www.bbc.co.uk/mediacentre/lat...lobal-audience

To put this 348 million in context the population of the world is 7.4 billion. I doubt the majority of licence fee payers would wish to fund 648 just for a few people driving around in the Benelux.
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Old 10-05-2016, 10:20
swb1964
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Until Katla eurpts and they find themselves stranded abroad with no source of news....
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