Full Freeview on the Crystal Palace (Greater London, England) transmitter
Brian Butterworth first published this on - UK Free TV
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?
BBC London 4.9m homes 18.4%
from London W1A 1AA, 12km north-northwest (335°)
to BBC London region - 55 masts.
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 AM/FM Crystal Palace TV region BBC London LondonWhich companies have run the Channel 3 services in the Crystal Palace transmitter area
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Wednesday, 9 May 2012
T
Tony9:01 PM
jb38: The plot thickens.
I would have explained earlier (I thought this issue was a simple one, wrongly), but I have a fairly complex setup. My aerial goes into a 0-20 attenuator and then into a Labgear 16 way destribution unit. Four of the outputs from the Labgear go to my WMC PC. Four others go to TVs throughout the house, three of which are HD ready, but don't have Freeview HD. Therefore, I get the HD from WMC extenders attached to my WMC PC (wired).
My Horizon meter shows channels 22, 23, 25, 26 & 28 having a signal strength of 30db. Using WMC I am able to see that all of these channels are giving signal qualities of 100%. As you say, the Horizon meter is no good for HD, so I can only diagnose that WMC reports the HD channel signal strengths are 60%.
WMC scans for channels by region (i.e. country) rather than by transmitter. So, when I setup the TV signal, WMC actually detects more than one source for certain channels. All but the Crystal Palace sources have inferior signal qualities. Where I live in Chelmsford, I get an unrestricted signal from Crystal Palace as I am quite high up with very few houses between me and the fall away of the hill I am at the top of. The aerial is setup to point slightly upwards of horizontal.
I have spoken to an aerial installer on the phone today and was told that the only way to be certain what might be wrong (if at all) is to do a survey. Sadly, they don't cover my area. So, I'll need to find a local installer (one I can trust as I've been stung before and am a bit wary now).
I hope this explains better my setup and how I am able to quantify the signal.
Thanks for your patience
Tony
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J
jb389:01 PM
Big Mart: If you enter your 4 digit password and carry out a "full rescan" there is no danger whatsoever of you affecting anything you have already stored, and although the TV at your other property isnt an HD model it doesnt really matter anyway, as you will still be able to see the actual HD channel that the Sony is picking up / recording but with you only being able to view it in SD.
Of course it would have been more preferable if you could have managed to try some other HD device on your present aerial system as what you have suggested is a second best but is certainly "still" worth a try, as if it records glitch free then it points to the signal you are receiving at your present location being sub standard.
As far as your other property is concerned, although I dont wish to appear as being a tad pessimistic, but I take it you have been in the area since any switchover activities (if that is) have taken place? as if you havent, then it brings another variable into the equation as far as the signal strength at your other property is concerned, although if its a Freeview TV then at least this will enable you to assess the situation regarding reception.
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Big Mart11:25 PM
London
jb38: I have been to the other property since switchover, and the television has been done.
However, since posting this, I can think of somebody only a few miles away from me that I could take it to. Although obviously not on the same aerial system, we share the same transmitter! (Don't know if his tv is HD - I doubt it!).
As I look up my street, the neighbours all seem to have Sky dishes. Certainly the ones that I know to talk to have dishes.
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Big's: mapB's Freeview map terrainB's terrain plot wavesB's frequency data B's Freeview Detailed Coverage
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jb3811:42 PM
Big Mart: It doesn't really matter where you can try the Sony so long as its on a different aerial system to that presently used, and if what you have mentioned is at all possible then all good and well and I would be most interested to know the outcome of your tests.
The other fact of you having mentioned that most other people in your street all seem to have Sky dishes can obviously be interpreted in two ways, as in most places where this is seen it can ring alarm bells insomuch that the area is one of bad reception, or of course that its just the case that Sky is favoured for reception, although in my experience its usually the former reason.
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Thursday, 10 May 2012
A
Alan Tuthill9:58 AM
Reading
My mother lost reception of ITV and ITV+1 last night 9/5/12. Is it possible to trace what repeater this was coming from?
RG5 postcode
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Alan's: mapA's Freeview map terrainA's terrain plot wavesA's frequency data A's Freeview Detailed Coverage
J
jb3810:05 AM
Tony: Having gone over everything you have reported and noting the info regarding the distribution amplifier etc given on your latest update, I would like you to try your Horizon meter connected directly onto the end of the aerial lead before it goes into anything, as although the 30db reading you have reported is quite capable of giving good reception it should really be quite a bit higher than this (45db+) to keep well above the reception threshold of the tuner, or the slight variations in signal levels that occur on a daily basis due to weather conditions etc can start to cause problems.
The other unfortunate aspect about your set up is that you do not have any way of checking the HD reception via the aerial system used except on your WMC card, and there isn't enough info around about this device (the card) regarding its performance to be able to assess certain aspects about its performance, like for example if its known to be stable on a channel that has a negative offset on its frequency such as applies with C/P's HD mux, this being why I enquired if you had tried to receive HD from Sudbury as it transmits bang on frequency.
If your Horizon is giving a reasonably accurate indication of the signal strength you receive then take the attenuator out of line, as rather than attenuate the signal it could benefit from a slight boost, so if you find that the signal level is higher directly from the aerial than when measured at the WMC, then for a test link the aerial directly onto the coax that's used to feed to the WMC, giving an update on results.
It would be interesting though to know what kind of results you would get if your aerial was directed towards Sudbury rather than Crystal Palace
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TW15 1LU10:57 AM
Ashford
Sirs,
I have found that the addition of a High Pass Filter, to ones aerial wire can vastly improve reception. It does this by cutting out the transmissions from cab radios, radio hams and generalUHF interference. Obviously, the signal strength reaching your TV is affected but inbuilt amplifiers can take care of that. A real pleasure to watch with one of these fitted.
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TW15's: mapT's Freeview map terrainT's terrain plot wavesT's frequency data T's Freeview Detailed Coverage
J
jb3812:33 PM
Alan Tuthill: Go into the signal checking screen and observe the mux channel number thats shown associated with the strength / quality indication, if Ch26 its Crystal Palace whereas if Ch42 its Hannington, the only other alternatives are so low in level that its doubtful if they would be received.
By the way the BBC match for these channels is Ch23 (C/P) and Ch45 (Hannington).
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Tony8:05 PM
jb38: Thank you for your detailed analysis of my situation.
I will try what you suggest and take the attenuator out of the system and measure the reading on the Horizon meter straight from the aerial. I have to say that, as you also suggest, I was expecting a much higher db reading after switchover since the wattage should have gone up to 200,000 watts. It occurs to me that the Horizon meter might be limited to what it can display - so I'll contact Horizon to ask that question.
To switch my aerial around to Sudbury I would need to get a tv engineer out and that is out until I establish the true state of affairs.
FYI, I am using BlackGold BGT 3620 cards in my WMC PC.
I'll get back to you when I have tested the points above. Sigh.....
Tony
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Friday, 11 May 2012
T
Tony5:52 PM
jb38: Okay. I think I've got the story straight.
Firstly, I've been abit of a klutz and was not reporting the correct signal category from my Horizon meter. What I should have reported is as follows:
Channel dbuv
22 56
23 59
25 60
26 62
28 63
These values, which are direct from the aerial, seem to be well over the value predicted by the 'UK digital TV reception predictor' which suggests the normal value to be 46. So, it looks like there is nothing wrong with my setup. I have now removed the attenuator and a couple of splitters I had in my system. The readings after the signal has been distributed by the Labgear splitter are as follows:
Channel dbuv
22 63
23 64
25 65
26 66
28 67
The SN readings from the Horizon meter are showing no errors.
I telephoned Horizon and spoke to a very helpful chap who indicated that HD reception will never give the same signal qualities as standard channels - he said that some meter manufacturers fiddle the signal scale for HD channels to make it seem that the signal qualities are the same for standard and HD channels. He thought that a signal quality for HD of 60% compared to 100% for standard channels is about right.
Does all this make sense to you?
Tony
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