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RTE Long Wave 252 reprieve ?


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Old 14-10-2016, 23:11
Ex Pat
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I believe that RTE have said that the mast insulators/stay wires will need to be replaced before the end of the decade ?
I think they would replace the insulators every 30 years. It was about that for the Tullamore mast.
I also think its the same with the BBC.
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Old 14-10-2016, 23:59
Maggie_King
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I think they would replace the insulators every 30 years. It was about that for the Tullamore mast.
I also think its the same with the BBC.
Tullamore 567 was taken off air for an number of months while that job was being done in 2004, without any fuss at all but a couple of years later when it was announced that it was closing for good, certain people whipped up a frenzy claiming that elderly people wouldn't know what to do
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Old 15-10-2016, 08:39
hanssolo
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Tullamore 567 was taken off air for an number of months while that job was being done in 2004, without any fuss at all but a couple of years later when it was announced that it was closing for good, certain people whipped up a frenzy claiming that elderly people wouldn't know what to do
Presumably RTE were looking for a new commercial operator to take on 252 from 2002 when Teamtalk closed to 2006, when no operator came forward and they had to chose from closing 567 or 252. They chose to close 576 and the 567 mast work was effectively waisted, and some listeners to the religous and sports programmes had to get sets with long wave if their sets in 2008 did not have it?

Wonder had the analogue signal remained on 567, and 252 could have became DRM full time (rather than just overnight) with help from commercial groups. Also Roberts (as a leading radio set brand, rather than Morphy Richards) released their DRM prototype set in High Street shops with the help of Radio Luxemburg and religous stations on SW, DRM might have taken off in UK and Ireland? But sadly was not to be.

Now to replace guys and insulators (one of which holds the whole weight of the mast) at Clarkstown before 2020 will be expensive, and RTE have decided to take the opertunity to close the site in 2017.
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Old 15-10-2016, 16:45
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...Wonder had the analogue signal remained on 567, and 252 could have became DRM full time (rather than just overnight) with help from commercial groups. Also Roberts (as a leading radio set brand, rather than Morphy Richards) released their DRM prototype set in High Street shops with the help of Radio Luxemburg and religous stations on SW, DRM might have taken off in UK and Ireland? But sadly was not to be....
Even if DRM30 receivers had become widely available, one of the findings of the Project Mayflower Trial was that fully to unlock the performance improvement possible with DRM30, it would be necessary to re-plan MW networks around a larger number of lower power TXs, so that field strengths never fall below the digital cliff threshold. The Beeb also suggested relaxation of the AM-DRM backoff for stations wishing to convert, although this is less of a show-stopper particularly as AM and DRM mean powers are already dissimilar due to COFDM's crest factor.

After the Plymouth trial DRM30 was effectively dead, as the Bright Young Things at the Beeb were already down on the "ancient modulation" network, never mind being asked to cough for roughly three times the number of site locations for an SFN. Had there been sets available though, DRM from Clarkstown would have been a winner due to the much greater night-time coverage area alone, never might any of the other quality benefits.

BIB. Inductors and coils are the same things. The ATU, or matching unit, is to match the base impedance of the antenna to the transmitter/feedline. It doesn't actually tune the aerial.
<scratches head>Still recovering from the traditional Friday evening shenanigans here, but isn't that the same thing? What does BIB mean?

Third year 'Electrical Machines' lectures at Glasgow Uni are now quite hazy in Vectorsum's bonce, but I thought that inductors 'induced', i.e. you needed either a self-tap or a coupled/coaxial counterpart inductor to have current 'induced' in it by the lines of magnetic flux. Coils simply act in-line to present an inductive impedance, i.e. voltage preceding current by 90 degrees.

Having said that, I can only think of one true instance of a coil around an AM site, the coil that usually forms part of the earth side of the lightning flashover assembly.

Most if not all phoneline RFI filters I have seen are bandpass, not notch. They usually come in different ranges. e.g. 500 KHz to 1.5 MHz.
Chances are that the filters used there are good for the whole LW band. Incidentally, I've used the ASDL filters with reasonable good success for eliminating RFI on my phone.
I think you mean band-stop instead of bandpass? Sure you can use band-stop filters as well, but you need twice the number of components as each side of the incoming two wires needs a filter due to poor common-mode rejection in the phone plus attachment cord. An RF notch filter, OTOH, is just an L and a C in series, shunting the line as close to the phone as practical. A disclaimer being that, same as everyone else posting here, I've no idea what RTÉ has dished out to the punters around Summerhill.
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Old 15-10-2016, 19:07
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[quote=Vectorsum;84230600

<scratches head>Still recovering from the traditional Friday evening shenanigans here, but isn't that the same thing? What does BIB mean?

Third year 'Electrical Machines' lectures at Glasgow Uni are now quite hazy in Vectorsum's bonce, but I thought that inductors 'induced', i.e. you needed either a self-tap or a coupled/coaxial counterpart inductor to have current 'induced' in it by the lines of magnetic flux. Coils simply act in-line to present an inductive impedance, i.e. voltage preceding current by 90 degrees.

Having said that, I can only think of one true instance of a coil around an AM site, the coil that usually forms part of the earth side of the lightning flashover assembly.

[/QUOTE]

BIB means Bit in Bold.
A coil provides the inductance, therefore an inductor, in this instance it's simply a coil. You may find 1, 2 or 3 in an AMU depending on the arrangement.
There are other ways of getting inductance, but not relevant here.
I'm not sure of the "one true instance of a coil" is that you're referring to.
There is a static drain choke, also a coil, connected directly to the feed to the mast after the AMU to drain any build up of static to earth. This has NOTHING to do with lightning protection.
The only other "coil" is a large single turn often found on the mast side of the AMU feedthrough insulator . This is to add delay if lightning does get through.
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Old 15-10-2016, 22:44
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BIB means Bit in Bold.
A coil provides the inductance, therefore an inductor, in this instance it's simply a coil. You may find 1, 2 or 3 in an AMU depending on the arrangement.
There are other ways of getting inductance, but not relevant here.
I'm not sure of the "one true instance of a coil" is that you're referring to.
There is a static drain choke, also a coil, connected directly to the feed to the mast after the AMU to drain any build up of static to earth. This has NOTHING to do with lightning protection.
The only other "coil" is a large single turn often found on the mast side of the AMU feedthrough insulator . This is to add delay if lightning does get through.
This is skidding completely OT but what I mean is the coil you can see in these pics of Ingřy as one example. The rising edge of any direct lightning strike Fourier transforms to high frequencies to which the 'pigtail' coil presents a high enough impedance that these preferentially break down the air gap either side of the probes attached to the corona rings, (hopefully) conducting the entire strike to earth.

But in any case that protective action doesn't depend on the tuned frequency of the ATU; my main point several posts ago was that the bits and bobs in the ATU itself are likely to have been built with a narrow adjustment range around 252 kHz in mind. The assembly is unlikely to be able to cope with a 10% change in operating frequency to 279 kHz without a major or more likely complete rebuild, in the fantastically unlikely scenario that RTÉ thinks that both keeping Clarkstown and changing frequency to 279 kHz are a great idea. There's not a prayer that RTÉ would fork out for this kind of investment.
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Old 15-10-2016, 22:56
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Do you think 2RN will have the mast removed if/when 252 shuts down ?
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Old 15-10-2016, 23:25
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But in any case that protective action doesn't depend on the tuned frequency of the ATU; my main point several posts ago was that the bits and bobs in the ATU itself are likely to have been built with a narrow adjustment range around 252 kHz in mind. The assembly is unlikely to be able to cope with a 10% change in operating frequency to 279 kHz without a major or more likely complete rebuild, in the fantastically unlikely scenario that RTÉ thinks that both keeping Clarkstown and changing frequency to 279 kHz are a great idea. There's not a prayer that RTÉ would fork out for this kind of investment.
You are simply wrong!
I have explained why earlier. I'm not going to repeat myself.
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Old 15-10-2016, 23:49
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This is skidding completely OT but what I mean is the coil you can see in these pics of Ingřy as one example. The rising edge of any direct lightning strike Fourier transforms to high frequencies to which the 'pigtail' coil presents a high enough impedance that these preferentially break down the air gap either side of the probes attached to the corona rings, (hopefully) conducting the entire strike to earth.
You've been Googling a lot.
Yes, that's the other coil. It has low inductance.
Not all installations use it.
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Old 15-10-2016, 23:53
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Do you think 2RN will have the mast removed if/when 252 shuts down ?
Would make more sense than replacing the insulators and have it sitting there doing nothing.
Other option would be to get someone else take it over but what are the chances of that.
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Old 16-10-2016, 00:09
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You've been Googling a lot...
Steady on old chap. Anything with the evil *google* in the domain name never gets past /etc/hosts here. AltaVista/Yahoo Search all the way.... Unless someone turns up that's actually worked on Clarkstown and can enlighten us as to whether the fat being chewed on this thread in terms of options for the future can actually be turned into reality, we're neither of us any the wiser.
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Old 16-10-2016, 00:20
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Would make more sense than replacing the insulators and have it sitting there doing nothing.
Thats what they did with Tullamore tho
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Old 16-10-2016, 01:12
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Thats what they did with Tullamore tho
Yes of course but they did use it for a while after the makeover. I guess at the time it was expected to continue for longer.
That really was a waste of money.
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Old 16-10-2016, 09:45
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In 2004 RTE must have been confident they will find another commercial partner to replace RTL and Teamsport for 252 and keep 567 for radio1. But by 2008 no commercial operator partner was forthcoming and DRM was not going to work in Europe.
The main save 252 campaginers still think RTE 252 has a long term future in drm mode, they have been waiting for that shipment of drm radios to come to the uk market from India since about 2005 http://www.twitter.com/EndaOKane/sta...1911921665?p=v
After the Plymouth trial DRM30 was effectively dead,
Looked promising in 2005/2006 but sadly did not work, the DRM consortium are still hoping DRM will work in India where 18khz is possible with dual analogue and digital signals which was not possible in Europe. But even now sets are still not in mass production in China or India.
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Old 17-10-2016, 15:32
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...Looked promising in 2005/2006 but sadly did not work, the DRM consortium are still hoping DRM will work in India where 18khz is possible with dual analogue and digital signals which was not possible in Europe. But even now sets are still not in mass production in China or India.
It depends how you define "didn't work". Apart from the findings about night-time performance the tech worked very well wherever it was trialled. Even the night-time performance would have been mitigated if it had been DRM30 vs DRM30 in the same co-channel, rather than high-powered AM.

DRM30's failure to get traction with broadcasters shows that it's not enough to demonstrate technical success, you also have to have a champion or champions within broadcasters in order to compete for finite resources. It didn't do anything spectacularly well that couldn't be done by other means, and unlike DAB and before that FM wasn't a solution to any outstanding quality or listener-experience problem, so was just ignored by decision-makers. As has already been demonstrated from country to country, these had already mentally consigned their AM networks to the scrapheap anyway, before DRM30's advent.

What the exercise has achieved, though, is put down a placeholder for a future wholesale replanning of the AM bands, including shortwave. If the ITU's mindset can be changed to accepting 20 kHz channelisation as the way forward, then we might be in business again. The big question is, who will get the setmakers on board? There was a window of opportunity with set-piece broadcaster/captive audience situations with RTÉ1X/Clarkstown that is now gone, where is the next opportunity going to come from? A community radio DRM30 deployment, perhaps?
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Old 18-10-2016, 10:30
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What would happen if the insulators weren't replaced? Could the mast tip over? When was the last time the Droitwich masts had new insulators fitted ?
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Old 18-10-2016, 12:32
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Great shame there are no commercial broadcasters who could/would be able to make use of it leased back from RTE. But would a LW station such as this cover its costs. ??? Difficult.
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Old 18-10-2016, 13:33
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Great shame there are no commercial broadcasters who could/would be able to make use of it leased back from RTE. But would a LW station such as this cover its costs. ??? Difficult.

Probably the most likely candidate would be something like China Radio International, timesharing with RTE R1 to keep at least some RTE service on air. But would RTE and the Irish government be happy to be associated with this sort of service? Would it be clear what was CRI and what was RTE?

They could also talk to religious broadcasters, but again similar issues would occur.


Sadly I still think it is time to let go and spend the money on other platforms.
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Old 18-10-2016, 20:33
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Sadly I still think it is time to let go and spend the money on other platforms.
Indeed, the roll out of DAB in the ROI really should be the priority at this stage. The current state of affairs is appalling.
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Old 19-10-2016, 00:31
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DAB rollout in the Republic seems to have been abandoned around May 2013. At least, that's the point when the dedicated 'Digital Listening' pages on the RTÉ website were folded back into the 'Ways to Listen' page. None of the rest of RTÉ/2RN's thinking seems particularly joined up, why should DAB be any different.
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Old 19-10-2016, 07:11
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DAB rollout in the Republic seems to have been abandoned around May 2013.
2013 is when the Irish Goverment stopped paying free licence fees for pensioners and passed it on to RTE causing a loss and start of cutbacks (incuding 252 and DAB rollout?)
http://www.irishtimes.com/news/polit...fare-1.1662320
“RTE’s public funding has been reduced to make a saving in the budget of the Department of Social Protection. In effect, RTÉ is being asked to bear the cost of national welfare policy.”
With other costs and drop in ad revenue the loss has now increased to 20m euros.
http://m.independent.ie/business/med...-35039198.html
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Old 21-10-2016, 23:01
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I wonder do the locals stilll want the mast to go http://www.rte.ie/archives/2015/0928...2-one-year-on/
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Old 22-10-2016, 09:47
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Who's decision was it to close 252? RTE or RTL?
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Old 22-10-2016, 09:56
Maggie_King
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Who's decision was it to close 252? RTE or RTL?
Well RTL sold their share to Teamtalk media, who rebranded and relaunched it as Teamtalk 252 and of course Teamtalk 252 went bankrupt after only 6/7 months
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Old 11-11-2016, 18:15
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No, knock out the carrier frequency and that's pretty much it. The stray audio arises from old-fashioned envelope detection at spurious non-linear junctions, so no envelope = no detection. For normal speech frequencies, as carried by RTÉ 1 Extra, most of the energy is concentrated around +/- 2 kHz. So a notch on 252 kHz is going to leave pretty much just higher sideband energy which, if it's audible at all, will just sound like periodic background noise and won't be obtrusive.
Just to clarify, 252LW usually carries the regular RTE Radio 1 (as on FM) service not the digital radio service (on DAB/DTT/online) called 'RTE R1 Extra', EXCEPT on Sunday mornings when religious output is on LW and RTE Radio 1-Extra and also for occasional sports outputs.

There is sideband energy beyond 2kHz, otherwise it would sound extremely muffled (notwithstanding that many modern receivers sound that way on MW/LW due to the poor design of the receivers!).
Any filter would have to knock out all the sidebands as well as carrier, an AM receiver (or anything acting as an AM receiver) will receive SSB (or DSBSC) transmissions for instance as an unintelligible 'duck quack' type sound despite no carrier present.
I remain unconvinced that a suggested move to 261kHz (just 7kHz higher than the original frequency used - 254kHz ) would have an impact on telephone line filters.
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