Full Freeview on the Emley Moor (Kirklees, England) transmitter
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The symbol shows the location of the Emley Moor (Kirklees, England) transmitter which serves 1,550,000 homes. The bright green areas shown where the signal from this transmitter is strong, dark green areas are poorer signals. Those parts shown in yellow may have interference on the same frequency from other masts.
Are there any planned engineering works or unexpected transmitter faults on the Emley Moor (Kirklees, England) mast?
Emley Moor transmitter - Emley Moor transmitter: Possible effect on TV reception week commencing 25/11/2024 Pixelation or flickering on some or all channels 
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Digital television services are broadcast on a multiplexes (or Mux) where many stations occupy a single broadcast frequency, as shown below.
64QAM 8K 3/4 27.1Mb/s DVB-T MPEG2
DTG-12 QSPK 8K 3/4 8.0Mb/s DVB-T MPEG2
H/V: aerial position (horizontal or vertical)
Which Freeview channels does the Emley Moor transmitter broadcast?
If you have any kind of Freeview fault, follow this Freeview reset procedure first.Digital television services are broadcast on a multiplexes (or Mux) where many stations occupy a single broadcast frequency, as shown below.
64QAM 8K 3/4 27.1Mb/s DVB-T MPEG2
DTG-12 QSPK 8K 3/4 8.0Mb/s DVB-T MPEG2
H/V: aerial position (horizontal or vertical)
Which BBC and ITV regional news can I watch from the Emley Moor transmitter?
BBC Look North (Leeds) 1.9m homes 7.4%
from Leeds LS9 8AH, 22km north-northeast (22°)
to BBC Yorkshire region - 56 masts.
ITV Calendar 1.9m homes 7.4%
from Leeds LS3 1JS, 22km north-northeast (16°)
to ITV Yorkshire (Emley Moor) region - 59 masts.
All of lunch, weekend and 80% evening news is shared with Belmont region
Are there any self-help relays?
| Derwent B | Active deflector | 74 homes | |
| Derwent C | Active deflector | (second level) | |
| Dunford Bridge | Active deflector | 14 km S Huddersfield | 15 homes |
| Hmp Leeds | Transposer | 30 homes | |
| Thixendale | Transposer | 25 km ENE York | 40 homes |
How will the Emley Moor (Kirklees, England) transmission frequencies change over time?
| 1956-80s | 1984-97 | 1997-98 | 1998-2011 | 2011-13 | 5 Feb 2020 | ||||
| VHF | B E T | B E T | B E T | B E T | W T | ||||
| C10 | ITVwaves | ||||||||
| C32 | com7 | ||||||||
| C33 | SDN | ||||||||
| C34 | com8 | ||||||||
| C36 | ArqA | ||||||||
| C37 | C5waves | C5waves | |||||||
| C39 | _local | ||||||||
| C41 | C4waves | C4waves | C4waves | BBCB | BBCB | ||||
| C44 | BBC1waves | BBC1waves | BBC1waves | D3+4 | D3+4 | ||||
| C47 | ITVwaves | ITVwaves | ITVwaves | BBCA | BBCA | ||||
| C48 | ArqB | ArqB | |||||||
| C51tv_off | BBC2waves | BBC2waves | BBC2waves | SDN | |||||
| C52tv_off | ArqA | ||||||||
| C55tv_off | com7tv_off | ||||||||
| C56tv_off | LLS |
tv_off Being removed from Freeview (for 5G use) after November 2020 / June 2022 - more
Table shows multiplexes names see this article;
green background for transmission frequencies
Notes: + and - denote 166kHz offset; aerial group are shown as A B C/D E K W T
waves denotes analogue; digital switchover was 7 Sep 11 and 21 Sep 11.
How do the old analogue and currrent digital signal levels compare?
| Analogue 1-5 | 870kW | |
| SDN, ARQA, ARQB, BBCA, D3+4, BBCB | (-7dB) 174kW | |
| com7 | (-12dB) 54.8kW | |
| com8 | (-12.3dB) 51.2kW | |
| Mux 1*, Mux 2*, Mux B*, Mux C* | (-19.4dB) 10kW | |
| Mux A*, LLS | (-22.4dB) 5kW | |
| Mux D* | (-23.4dB) 4kW |
Which companies have run the Channel 3 services in the Emley Moor transmitter area
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Thursday, 20 October 2011
mike Roberts : They are all at the same strength in terms of ERP, but the radiation patterns may not be identical.
However, I don't actually know or not, because the information was redacted as a "state secret" when I asked the BBC for the information.
You may also have interference from other transmitters on the same frequencies.
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Mike Dimmick3:22 PM
mike Roberts: A number of propogation conditions can mean different frequencies travel more or less well. In general, the higher the frequency, the less it bends over terrain, so you would normally expect - from the wrong side of the Pennines - that the higher frequencies will be less strong than the lower ones. In addition, reflections - causing multiple paths from the transmitter to your aerial - interact differently with different wavelengths (the difference in path length is a different number of wavelengths at different frequencies) and therefore their effect on signal strength can cause changes through measurement.
The power levels as stated are envelope power limits, not absolute limits. In the worst case the different carriers making up the signal could all align the same way at one instant, or all different directions at another instant - the difference between these two conditions is potentially 76 dB! In practice the peak-to-mean ratio is clipped at 7-10 dB, but this is still enough for programme content to mean that different muxes with the same nominal maximum power output read at different levels (source: BBC RD - Publications - White Paper 156 DVB-T and Voltage Ratings of Transmission Equipment ).
Really, the box should measure the size of the pilot and TPS carriers, which do *not* change amplitude (though they do change phase), rather than the whole bandwidth, but that is the customary approach.
Finally, as Brian says, there may be differences in the radiation patterns. The radiation pattern of a full transmitting antenna is made up by combining many smaller elements. The UHF aerial for Emley Moor's second mast (this collapsed before the current tower was built) was eight tiers of 6 panels, each panel carrying 4 elements (8 *components* were fitted to each panel, but the active part was the vertical slot *between* the components, odd as that may sound). Again, the slots behave slightly differently at different frequencies - optimal resonance is achieved at 1/4 of the wavelength, so you can never tune the response of an aerial carrying more than one service perfectly for all of them. The overall radiation pattern is made up by the reinforcing and cancelling signals from each element on each panel.
That original antenna contained transformers to feed only 60% of the power into the two panels in each tier on the south-west face, compared to the other two faces. Pushing any more power into the Pennines was considered a waste. You can see the BBC's report on that antenna at BBC RD - Publications - R&D Report 1966-47 : UHF transmitting aerial for the Emley Moor Television Station , particularly how its radiation pattern differed at C44 (BBC One) and C51 (BBC Two).
Because the Emley Moor tower is now a listed building, the external appearance had to remain the same even while changing the antennas inside the fibreglass shrouds at the top of the mast. In turn, though, that meant that Arqiva didn't have to apply for planning permission to change the antennas as they had at most other sites. So we don't know anything about what the new aerial is like and what its radiation pattern might be.
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Mike Dimmick: That document is interesting. Why might they have decided to implement differing radiation patterns for the two channels? What was the point of this?
The chart published elsewhere by UK Free TV showing the number of homes served by Emley Moor indicates that not all will receive both PSB and commercial muxes:
The commercial multiplex after switchover: ArqA, ArqB and SDN | ukfree.tv - independent free digital TV advice
Presumably some at the fringes will only be able to receive the PSBs.
This is despite them all being listed as having the same ERP of 174kW.
Is this evidence that the radiation patterns of the PSBs and Coms are different? (DN31NJ)
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mike Roberts 5:50 PM
Wigan
HI mike is it different then for FM radio? as west yorkshires local radio station the pulse, signal travels well into Greater Manchester as far has Bolton and beyond, you would be able to get it here if wish Fm was not more or less on the same frequency which is 102.5 which is fairly high up on the FM frequency list.
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mike's: mapM's Freeview map terrainM's terrain plot wavesM's frequency data M's Freeview Detailed Coverage
Friday, 21 October 2011
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Mike Dimmick4:40 PM
mike Roberts: As FM radio is on a lower frequency, it bends more over terrain and so can travel further than UHF television.
The radiation patterns for radio transmitters *are* published by Ofcom, and you can see the one for Emley Moor at FM, MW and LW radio broadcasting | ukfree.tv - independent free digital TV advice . However, The Pulse broadcasts from Vicars Lot, a site several miles to the west and omnidirectional: Vicars Lot analogue radio transmitter | ukfree.tv - independent free digital TV advice .
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Mike Dimmick5:04 PM
Dave Lindsay: The antenna would have been designed to minimize the differences between channels, but it's an inevitable consequence of having multiple channels share one aerial, that the radiation pattern of each channel is a bit of a compromise.
The picture is somewhat exaggerated as engineers normally measure differences in decibels (dB) while those graphs are shown in relative volts. To convert, take the base-10 logarithm of the voltage ratio ('log' on most calculators, LOG10 in Excel) and multiply by 20.
Giving each channel its own antenna at the same site would still be a compromise, as the coverage area is also affected by the aerial's height. Each antenna could be shorter - fewer tiers - to reduce the differences in height, but that would reduce the gain of the aerial and increase the electrical power needed to produce the same output.
In the US, it seems to be common to erect a tower with quite a wide platform that the various antennas then are mounted on - where they do share sites at all. The Empire State Building is festooned with different aerials.
As it is, the commercial multiplexes at Emley Moor are on an aerial slightly further down the mast (about 11.5 metres) than the PSB multiplexes, presumably so that each can be optimized better for the frequencies it's carrying, though it will also offer greater redundancy. The other issue is that the commercial muxes clash more with transmissions from other sites (e.g. Nottingham also uses 48/51/52) and with PSB transmissions from the relay transmitters - both co-channel, using the same channel at both sites, and adjacent-channel interference, due to the imperfect nature of the transmitter - some power leaks into adjacent channels. It is filtered, but filters with a less sharp roll-off are permitted at lower-power sites, therefore more leakage. This only affects the residents near to that site, but it still ends up reducing coverage.
There's a possibility that Emley Moor ArqB might currently be restricted to half power to avoid damage to the low-power Mux 1 at Pontop Pike - there is provision for that in Ofcom's licence documents.
Signal propogation is slightly frequency-dependent, and higher frequencies don't travel quite as well as lower ones, nor carry along cables quite as well. I also mentioned multi-path effects before.
All this put together means you may see different levels across the various multiplexes, and those differences may change over time, despite the published maximum ERPs being identical.
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Sunday, 23 October 2011
Mike Dimmick: Does each mux have its own set of panels then?
Why the gap of 11.5m?
I assumed that underneath the fibreglass shroud there would be rows of panels (without gaps) similar to these being installed at Sandy Heath:
mb21 - The Transmission Gallery (DN31NJ)
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Monday, 24 October 2011
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Mike Dimmick1:24 AM
Dave Lindsay: It's helpful to cross-reference with Arqiva's Reference Offer for Network Access from 2005.
Useful documentation
Emley Moor was originally an IBA transmitter so you'll find it under the Arqiva offer, rather than the ex-NGW (former BBC transmitters).
If you look at Appendix 3, List of Main Stations, you'll see that they intended to construct one antenna for the PSBs, and one for the COMs. The reserve antenna can act for the PSBs or for the COMs but not both at once.
My belief is that the two main antennas, PSB and COM, simply sit on top of one another with the PSBs on top, giving the appearance of forming a single antenna. The difference of 11.5 metres is the distance between the centre points of the two antennas (Ofcom use average height). Each antenna is constructed in halves to allow half-antenna running. Each panel is 1.09m in height - if they're using Radio Freqency Solutions' PHP panels - which would suggest 10 tiers, five tiers in each half antenna.
Sandy Heath's data is odd - Ofcom are listing SDN at the same height as the PSB muxes, which doesn't sound right (and the difference between the two is only 2.7m). It would certainly make sense to put 48/51/52 on a different antenna from 21/24/27. Arqiva did project a Class 2 antenna system, each antenna able to offer half-working (at 6 dB down) so I assume that the top 6 tiers are one antenna for PSBs (in 2 x 3 tiers) and the bottom 6 for the COMs.
The reason I say we don't know exactly what's in there is that at other sites, e.g. Winter Hill, the main antenna is a wrap-around of the main lattice structure - I assume RFS PHP12S which have 12 panels per tier - and at others, e.g. Hannington and Dover, the structure has five faces, e.g. RFS PHP5S. At Dover, only three of the five faces have panels fitted, to reduce the amount of power sent into France.
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mike Roberts 11:51 AM
Wigan
A few years ago I was in a bed and breakfast in Blackpool and I was flicking through the channels in my room, and came across a fussy calendar news, I checked the channel on the tuning menu and it was on 47. It just shows you the strength of Emily moor to be received over 80 miles away, I wonder if it still reaches Blackpool. And it probably makes it the only transmitter in the UK that can be received on both the west and east coasts?
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mike's: mapM's Freeview map terrainM's terrain plot wavesM's frequency data M's Freeview Detailed Coverage
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Andy4:01 PM
Leeds
Hi, Is anyone having problems with the Emley Moor transmitter as during the day where I live , the signal is great and I get nearly every channel going. But during the evening BBC channels and a few others go off and I get a weak signal. ITV channels do break up.
It just seems strange to have it happening every day in the evening.
I'm mainly wanting to sort this out as I'm looking at topping up for Sky Sports, but I can't see the point of doing it if the signals going to be doing this every time.
Cheers
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Andy's: mapA's Freeview map terrainA's terrain plot wavesA's frequency data A's Freeview Detailed Coverage
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