Full Freeview on the Sandy Heath (Central Bedfordshire, England) transmitter
|Google Streetview||Google map||Bing map||Google Earth||52.130,-0.242 or 52°7'47"N 0°14'33"W||SG19 2NH|
The symbol shows the location of the Sandy Heath (Central Bedfordshire, England) transmitter which serves 920,000 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.
This transmitter has no current reported problemsThe BBC and Digital UK report there are no faults or engineering work on the Sandy Heath (Central Bedfordshire, England) transmitter.
Which Freeview channels does the Sandy Heath 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.
1 BBC One (SD) Cambridge, 2 BBC Two England, 9 BBC Four, 23 BBC Three, 201 CBBC, 202 CBeebies, 231 BBC News, 232 BBC Parliament, 250 BBC Red Button, plus 15 others 700 BBC Radio 1, 701 BBC Radio 1Xtra, 702 BBC Radio 2, 703 BBC Radio 3, 704 BBC Radio 4 (FM), 705 BBC Radio 5 Live, 706 BBC Radio 5 Live Sports Extra, 707 BBC Radio 6 Music, 708 BBC Radio 4 Extra, 709 BBC Asian Network, 710 BBC World Service, 719 BBC Norfolk (BBC local radio), 720 BBC Three Counties (BBC local radio), 722 BBC Cambridge (BBC local radio), 734 BBC Northampton (BBC local radio),
3 ITV 1 (SD) (Anglia (West micro region)), 4 Channel 4 (SD) South ads, 5 Channel 5, 6 ITV 2, 10 ITV3, 13 E4, 14 Film4, 15 Channel 4 +1 South ads, 18 More4, 26 ITV4, 30 E4 +1, 35 ITV1 +1 (Anglia east),
56 5SELECT, 101 BBC One HD (England no regional news), 102 BBC Two HD (England), 103 ITV 1 HD (ITV Meridian Southampton), 104 Channel 4 HD South ads, 105 Channel 5 HD, 106 BBC Four HD, 109 BBC Three HD, 204 CBBC HD, 205 CBeebies HD, plus 1 others 66 TBN UK,
20 Drama, 21 5USA, 29 ITV2 +1, 32 5STAR, 33 5Action, 41 Legend, 42 GREAT! movies action, 46 Channel 5 +1, 58 ITVBe +1, 59 ITV3 +1, 64 Blaze, 67 CBS Reality, 74 Dave ja vu, 78 TCC, 81 Blaze +1, 89 ITV4 +1, 203 CITV, 208 Pop Player, 209 Ketchup TV, 210 Ketchup Too, 211 YAAAS!, plus 15 others Racing TV, Kiss Chat & Date, Proud Dating, ADULT Xpanded2, 16 QVC, 22 TJC, 237 TalkTV, 263 SonLife, 264 VisionTV, 265 On Demand 365, 269 Arise News, 670 ADULT Section (start), 724 Capital, 727 Absolute Radio, 728 Heart,
11 Sky Arts, 17 Really, 19 Dave, 31 E4 Extra, 36 pick, 40 Quest Red, 43 Food Network, 47 Film4 +1, 48 Challenge, 49 4seven, 57 Smithsonian Channel, 60 Drama +1, 70 Quest +1, 75 Yesterday +1, 83 Together TV, 233 Sky News, plus 9 others CRAFT EXTRA , 45 Gems TV, 85 Create & Craft, 673 ADULT smileTV3, 723 talkSPORT, 730 RNIB Connect, 731 Classic FM, 732 LBC, 733 Trans World Radio,
12 Quest, 25 W, 27 Yesterday, 34 GREAT! movies, 39 DMAX, 44 HGTV, 71 Quest Red +1, 73 HobbyMaker, 82 Talking Pictures TV, 84 PBS America, 88 Classic Hits, 235 Al Jazeera Eng, plus 19 others ADULT smileTV2, ADULT Studio 66, 37 QVC Beauty, 38 QVC Style, 51 Ideal World, 72 Jewellery Maker, 206 Pop, 674 ADULT Babestn, 678 Xpanded TV, 699 ADULT Section, 711 Hits Radio, 712 KISS FRESH, 713 KISS, 714 KISSTORY, 715 Magic, 716 Greatest Hits Radio, 717 Kerrang!, 718 Smooth Radio, 725 Premier Radio,
H/V: aerial position (horizontal or vertical)
Which BBC and ITV regional news can I watch from the Sandy Heath transmitter?
BBC Look East (West) 1.0m homes 3.7%
from Cambridge CB4 0WZ, 29km east-northeast (66°)
to BBC Cambridge region - 4 masts.
70% of BBC East (East) and BBC East (West) is shared output
How will the Sandy Heath (Central Bedfordshire, England) transmission frequencies change over time?
|1965-80s||1984-97||1997-98||1998-2011||2011-13||12 Feb 2020|
|VHF||A K T||K T||K T||W T||W T|
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 30 Mar 11 and 13 Apr 11.
How do the old analogue and currrent digital signal levels compare?
|BBCA, D3+4, BBCB||(-7.4dB) 180kW|
|SDN, ARQA, ARQB||(-7.7dB) 170kW|
|Mux 1*, Mux 2*, Mux A*, Mux B*, Mux C*, Mux D*||(-17dB) 20kW|
|Analogue 5||(-20dB) 10kW|
Which companies have run the Channel 3 services in the Sandy Heath transmitter area
Tim Newton: The model used on ukfree.tv is written by me, and is not that actual "UK Planning Model" because every time I have asked for it, I have been told it is a state secret, see Update on transmitter radiation patterns (BBC FOI request) | ukfree.tv - 10 years of independent, free digital TV advice for example.
The model used here on ukfree.tv is derrived from information provided by the OS, Ofcom and other bodies.
I am happy to provide anyone who wants it with the output of these calculations.
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I think I have solved my interference problem. Today I had fitted an A0968 28 element log periodic aerial, this replaced the 52 element HG10 WF aerial that was fitted. The improvement in reception is considerable. Although the gain of the new aerial is 4dB lower than the old one, the reception is greatly improved with no bit errors detected on any channel. I have to say the new aerial is mounted on a longer pole, putting the aerial 6ft higher above the roof top. But that said, it may now be necessary to turn down the gain of the distribution amp mux, as all Sandy Heath channel are at the top of the equipment signal strength range, close to overload on one of the DVRs.
Interestingly the new log periodic is smaller than the old aerial, and clearly offers a much lower wind loading.
What I do no understand is why the old aerial produced such poor reception only on one RF channel, channel 27.
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NJ: The reason why it only affected one UHF channel is probably down to the fact that they won't all be exactly the same. Had you had more gain, then maybe it would have started to affect other channels.
The is surely not to run it so high rather than wondering why one channel is degraded when others are not!
Digital reception requires good quality. Don't try to run it as close to full strength as possible.
With analogue, the stronger the signal the better the picture. With digital there is a threshold over which the signal can be received. Whilst it is a good idea to have a good margin over that threshold to allow for natural fluctuations, there is no need to strive for as high as you can as it gives no benefit to the picture.
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The argument that gain was the issue is clearly incorrect as my new aerial has a slightly lower gain than the old one and experiments were conducted using an aerial preamp that indicating front end gain was not a factor.
As I reported in my earlier postings, my receivers were all reporting high levels of signal, the problem was poor bit error rate.
The way in which the bit error rate changed with time of day suggested that the interferer was a strong reflection subject to Rayleigh or Rician fading.
Since the new aerial made such a difference, I can only conclude that either the old aerial had a notch in its frequency response due to an impedance mismatch problem, maybe the result of a poorly connected cable, which seems unlikely or the small increase in height and the slight change in aerial direction, was sufficient to mask the co-channel interferer. I will not know if the problem has been truly solved until we have experienced the full range of weather conditions.
Given the beam width of the old aerial is 32 degrees, the slight change in direction also seems unlikely to have resolved the problem.
It is worth note that the minimum front to back ratio of the new aerial is better than the old one, with large attenuation peaks across the band. A more complete comparison of the aerial specifications is impossible as the old aerial spec lacks the necessary gain plots.
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