Full Freeview on the Crystal Palace (Greater London, England) transmitter
Google Streetview | Google map | Bing map | Google Earth | 51.424,-0.076 or 51°25'26"N 0°4'32"W | SE19 1UE |
The symbol shows the location of the Crystal Palace (Greater London, England) transmitter which serves 4,490,000 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.
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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 Crystal Palace 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 Crystal Palace transmitter?
![regional news image](/styles/images/regionalnews/302x152/bbc-london.jpg)
BBC London 4.9m homes 18.4%
from London W1A 1AA, 12km north-northwest (335°)
to BBC London region - 55 masts.
![regional news image](/styles/images/regionalnews/302x152/itv-london.jpg)
ITV London News 4.9m homes 18.4%
from London WC1X 8XZ, 11km north-northwest (345°)
to ITV London region - 55 masts.
Are there any self-help relays?
Charlton Athletic | Transposer | Redeveloped north stand Charlton Athletic Football Club | 130 homes |
Deptford | Transposer | south-east London | 100 homes |
Greenford | Transposer | 12 km N Heathrow Airport | 203 homes |
Hendon | Transposer | Graham Park estate | 50 homes |
White City | Transposer | 9 km W central London | 80 homes |
How will the Crystal Palace (Greater London, England) transmission frequencies change over time?
1950s-80s | 1984-97 | 1997-98 | 1998-2012 | 2012-13 | 21 Mar 2018 | ||||
VHF | A K T | A K T | A K T | A K T | W T | ||||
C1 | BBCtvwaves | ||||||||
C22 | ArqA | ArqA | |||||||
C23 | ITVwaves | ITVwaves | ITVwaves | BBCA | BBCA | ||||
C25 | SDN | SDN | |||||||
C26 | BBC1waves | BBC1waves | BBC1waves | D3+4 | D3+4 | ||||
C28 | -ArqB | ArqB | |||||||
C29 | LW | ||||||||
C30 | C4waves | C4waves | C4waves | -BBCB | BBCB | ||||
C33 | BBC2waves | BBC2waves | BBC2waves | com7 | |||||
C35 | com8 | ||||||||
C55tv_off | com7tv_off | ||||||||
C56tv_off | COM8tv_off |
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 4 Apr 12 and 18 Apr 12.
How do the old analogue and currrent digital signal levels compare?
Analogue 1-4 | 1000kW | |
SDN, ARQA, ARQB, BBCA, D3+4, BBCB | (-7dB) 200kW | |
com7 | (-13.7dB) 43.1kW | |
com8 | (-14dB) 39.8kW | |
Mux 1*, Mux 2*, Mux A*, Mux B*, Mux C*, Mux D*, LW | (-17dB) 20kW |
Local transmitter maps
Crystal Palace Freeview Crystal Palace DAB Crystal Palace TV region BBC London LondonWhich companies have run the Channel 3 services in the Crystal Palace transmitter area
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Sunday, 10 June 2012
M
martyh10:45 PM
From martyh Ash Vale.
PICTURE PROBLEMS WITH FREEVIEW DONGLE.
Further to my postings regarding my digital TV and it being unable to use the new signal from April 4th, I purchased a scart plug in device (scart adapter) from Currys as suggested by jb38. It's a type that plugs in to a scart socket at the rear of my TV. However, I am extremely disappointed by the picture quality I'm getting and the fact that I have lost some part of the picture at the top and to the right of my screen. From the adapter remote menu, I would say that Im, getting (on average) about 80% quality and 80% signal (variable). My pictures lack true depth of colour and can also be grainy. I have also noticed colour saturation problems (especially black and white in lack of definition, for example no definition on suit lapels). I have tried adjusting elements such as sharpness, colour, contrast etc, using my TVs menu without success. In addition, I have also tried altering between the RGB and CVBS modes on the adapter remote menu. When I switch between the two the screen options, the picture moves (flickers) to the left like its offset. CVBS mode seems richer in colour but gives a less defined image, almost blurred. I have also selected combinations of 16:9 and 4:3, and combinations of these with the letterbox/full frame options. I have also tried several retunes, to see if that helps, to no avail, though I do get 115 TV and radio channels. Compared to the pictures I was getting on the 2k signal, direct through my TV Ariel into my TV, I am really not impressed with what I am seeing, especially as quality of pictures I now receive are actually straining my eyes. I thought the new format was supposed to be an improvement but it seems not. Any ideas. Please refer to my previous posts if youd like to revise. Thanks! Martyh. Manual for my adapter can be found here: http://documents.knowhow.….pdf
ps.I have had my adapter for about 4 weeks.
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Robert11:06 PM
Val Tilley: As a TV/Video amateur with a computer background what I understand is Error Pixels or block on the screen start to appear when the block of data which make up the video audio stream come through with uncorrectable (unrecoverable) data errors due to too much noise or interference on the modulated UHF signal from the aerial.
Digital transmission is fault tolerant, you can have a degree of noise or interference but it has to be within the bounds of the error correction circuits. This is its greatest strength. Your tuner not only knows the data is damaged but can correct it so the picture and sound generate are perfect so you never know but looking at the TV.
However, the fact the data had to be corrected is reported in the statistics used for either Signal Quality or bit rate error. This is a feature most tuner have somewhere in their menu structure.
Missing channel 12 (Yesterday) probably means that your tuner failed to find one of the Multiplexers. Crystal Palace transmits all TV and radio over six multiplexers. To check I my tuner has found each one I should have BBC1 (1), ITV1 (3), ITV3 (10), Pick TV(11), Yesterday (12) and BBC1HD(50). Information on what TV station is on what Mux is explained elsewhere on the website but BBC2 shares with BBC1, ITV1 shares with Channel 4 & 5.
My recent experience with automatic scanning suggest that it is not very fault tolerant. The TV's tuner had a perfect picture yet the PVR which I was tuning missed the Mux. I was just manually tuning the Mux with ITV1 on it yet Channel 4 and Channel 5 were not in the list yet worked if I tapped 4 or 5 on the remote. So not very robust either.
Missing muxes are a common problem if you were setting up to watch Freeview via an indoor aerial but prior to DSO finding the sweet spot for the aerial was a 5 or 10 minute task once found it was reliable. I never knew there were seven muxes before DSO because I did not have to be able to diagnose reception problems before.
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Monday, 11 June 2012
J
jb388:30 AM
martyh: Just to clarify a point insomuch that I did "not" recommend that particular brand of device to you, but had said that you should purchase a Freeview box or alternatively a Freeview adaptor and provided a link purely for reference purposes, the link being for a Konig brand device which is somewhat superior to anything with a Logic tag attached to it.
That said, have you went into this devices set up menu and selected settings to suit the TV you are using? this described on page 24, plus made sure that the same settings have been used on the actual TV? as your type of problem is usually caused by them having been set different to each over.
You have to also consider the other aspect concerning the level of Freeview signal you are receiving, as when your Philips TV stopped working after switch over this means that you will not be aware of the level of signal you are receiving from higher powered transmitters, and with neither myself or anyone else being able to assess this as you haven't provided a post code, or at least one from a nearby shop or pub, and a level predictor requires this info.
Maybe you could give an update on the aspects mentioned.
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martyh11:35 AM
From martyh GU12 Ash Vale Surrey/Hants
Hi jb38. Comments noted re Konig recommendation. If you read my previous posts, I did ask if it matters what make adapter was used, and had no reply, so thought any would do. No offence in my last post, as not blaming you on that. On settings, I have scart plugged into EXT1, and have selected this as my decoder on the actual TV settings. On the actual adapter remote menu have selected widescreen 16:9 (TV is widescreen), and full frame. Again, as per previous post have tried different settings on the logic and my TV menus to see if it makes a difference but it seems not to. The only thing I have not re-tried (again as it didn't seem make any difference at first set-up), is take an RF output from the logic to my TV Ariel 'in' socket. Re: signal levels. On the 2k signal pre April 4th (with Ariel plugged direct to my TV), I had 114 channels - all pulling in good pictures - and in full frame. However, built in to the TV there is a signal strength indicator, and for the most part it indicated signal strength to my location GU12 as always being poor - indication a red square, where red is poor, yellow good, and green excellent. Again, even so, I still got all the channels and very good pictures. Just to clarify that the Logic does have a signal quality and strength indicator, with bar type displays, and this is what I was referring to previously. As far as I can tell, I have unified both the Logic and TV settings. Hope this helps.
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S
Steve2:11 PM
I've been reading with interest the problems others are experiencing with their Freeview reception and it prompts me to ask a few basic questions:
First, I presume that transmitters are mounted on tall masts so as to ensure the signal emitted is presented with the least obstruction over the greatest possible distance - but what is the profile (shape) of the signal? Does it start off narrow and spread out wider with distance?
I note that several of the people with reception problems are quite close to the Crystal Palace transmitter and I understand that sometimes this might result in the signal they are receiving being too strong and requiring attenuation - but given the height of the mast, is it also possible to be so close to the transmitter that the signal passes over the top of a roof mounted aerial and hence misses it completely?
Finally, I live around 25 to 30 miles from CP and receive excellent freeview reception via an indoor aerial - obviously, the signal has to pass through the walls of my property - so why would something like leaves on a tree disrupt reception?
Thanks in advance.
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NICK ADSL UK 4:14 PM
There's just one other thing that i have just come across in that all leads that go into equipment need to be of quality as most leads do have a habit of starting out OK but then if moved or touched losing the connection for some odd reason
So it's vital that you use leads of a high standard to rule this out
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Mike Dimmick5:56 PM
Steve: Signals from plain dipoles are diffused in a ring-doughnut shape. With more tiers of panels connected in-phase with each other, you get more gain in one plane and a number of additional smaller lobes. There are some angles that would indeed get no or nearly-no signal, referred to as nulls. The antenna designer therefore adds small differences in the lengths of the connections to each panel, which has the effect of reducing the nulls, at the cost of some efficiency. This is called 'null filling'.
Also, the main lobe of the transmitted signal would normally be exactly horizontal, which - due to the curve of the earth - actually misses the ground completely. Again, the changes to the relative phases allow this to be adjusted down a bit so that the peak signal lands at a reasonable point just short of the horizon - this is called 'beam tilt'.
Both null-filling and beam-tilt adjustment are performed to ensure that even those living very close will get sufficient signal. It will be less than the full 200kW, but people living this close do not need anything like that amount of power.
We don't have the design for the current transmitting aerial, but the BBC report for the old analogue aerial, with graphs showing its performance, is available at http://downloads.bbc.co.u….pdf . The vertical radiation patterns are on p13-p15 (figures 10-12). One-tenth or one-twentieth of the field strength is still very high indeed, there are many local relays intended to serve areas 1-2km away from the mast that have less than 100W. There are transmitters with less than 2W output, indeed there are some 'Link' sites with less than 1W, although these are really to get the signal to another relay . People that close to CP are more likely to have too much signal than too little.
As for the leaves: I believe they're more effective at blocking radio signals at UHF than your walls are, because they're mainly water (even worse when wet leaves). They also move in and out of the path when the wind blows, making for a lot of additional variation.
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jb388:38 PM
martyh: With regards to your query as to whether it matters what make of adaptor is used, I have to apologise for missing that posting and which on searching back I see was made on April 25th @ 7.41pm, although I would always advise anyone thinking on purchasing any digital receiving equipment to avoid the cheap end of the market, the Konig I used for an example not being as well as having a reputation for good performance, albeit of course as with all digital equipment there will always be someone with a problem.
However, on studying what you have reported I see its really a case of you having two separate issues, that of the picture ratio being incorrect plus that you cant find a happy medium when trying to balance out the colours etc on the TV. Your TV has four ratio modes 16:9 / 14:9 / 4:3 and Auto format, so what happens if you leave it on Auto and try a combination of settings on the logic? because to put it in a factual way a satisfactory outcome can only be achieved by experimenting with the setting options offered on the device as nothing external can be done to alter this.
This also applies to the issue of the colour / contrast / brilliance etc settings, as you really have to start afresh with these settings due to the fact that all of your original picture settings were made to suit the sets internal circuitry, and so just like as with the issue of the screen ratio a satisfactory solution has to (and can only) be achieved by experimenting with the settings offered on the TV, because this problem just like as with the picture format issue, can only be rectified via the range of settings offered on the TV's menu
That said, it would be of interest to know what kind of results would be achieved if you temporarily tried the Logic on another TV, as that would soon reveal if there was a problem with the device, as to me anyway, the quirks associated with particular Logic device is an unknown quantity.
Finally, regarding the aerial link from the Logic to the TV, you can really leave that permanently disconnected as you are in effect only using the TV as a monitor anyway.
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Tuesday, 12 June 2012
S
Steve9:25 AM
Mike, Thanks for your detailed explanations and answers to my questions - the null filling and beam tilting is most interesting - I guess there must be an optimum distance between the transmitter and the horizon where reception is just about right. Not too close and not too far. So neither attenuation nor booster needed.
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Mike Dimmick: Thanks for the insight. I have some questions for you which I will be grateful if you can answer.
The PSB networks are different to the COM ones, coverage wise, with the latter being more restricted due to channels being re-used more often (distance wise from transmitters). I have seen that you have said that coverage is generally more often restricted by interference than propagation. Helping out on this site, I have seen a number of occasions where this has been seen to be so.
Some transmitters have COMs at the same ERP as the PSBs, but according to predictions, their will be some viewers who will only be able to pick up the PSBs. (See Freeview news | ukfree.tv - independent free digital TV advice )
Referring to the Arqiva "Reference Offer for the Provision of Network Access" (page 29), Emley Moor uses two sets of panels, one for PSBs and one for COMs. Both have an ERP of 174kW. Is it likely that the COMs antenna's beam is tilted lower than the PSB one (which might account for the difference in number of people served for each)? At my location, the COMs appear lower strength and turning the aerial off-beam, when the COMs start to break-up, the PSBs are still strong.
http://www.arqiva.com/cor….pdf
Then there are those whose COMs are at half-power to the PSBs. Midhurst is one such example and its Steyning relay currently broadcasts co-channel with two of Midhurst's COMs. This is an example which illustrates why the COMs are more restricted.
Midhurst isn't shown in that document, so take Stockland Hill as an example. It apparently uses one antenna system for all six muxes (all of which are in the 20s) and the COMs are at half the power of the PSBs.
Why do some transmitters have two antenna systems and some have one? I appreciate that where channels are far apart they are likely to have to have more than one. I presume that the tilt of the beam will be the same for Stockland's PSBs and COMs as it's the same antenna.
Is the answer to the question cost and the fact that there's little to be gained having different antenna systems with smaller transmitters and that reducing ERP is a much more effective (from a cost point of view) in restricting coverage?
Then there is Belmont. The PSBs are in the 20s at 150kW, COM4 is on C30 at 50kW and COM5 and COM6 are on C53 and C60 at 100kW each.
Obviously C53 and C60 can't have as big a footprint as the PSBs as these are re-used from Oliver's Mount, for example. Some in Filey receive from Oliver's Mount and some, including those low-lying on the sea front, receive from Belmont. So there is clear overlap.
The reason I mention Belmont is because of the apparent anomaly of COM4 being half-power to COM5 and COM6. Why is this?
According to the Arqiva document, the three PSBs and COM4 use one antenna system and COM5 and COM6 use another. This makes sense due to the channel spacings.
Is the reason that C30 is at lower power so that the signal doesn't carry as far (as it's being radiated from the PSB antenna)? And again, for cost reasons: instead of having three antenna systems; one for PSBs, one for COM4 (lower power and lower tilt that the PSBs) and another for COMs 5 and 6?
I am wondering if it is cheaper to restrict coverage by reducing ERP (for COM channels) whilst using the same antenna as the PSBs (e.g Midhurst, Stockland and Belmont COM4). But for the larger transmitters it is more financially viable to have two antenna systems, even where all channels are close to each other (e.g. Emley Moor and I presume Crystal Palace).
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