Full Freeview on the Mendip (Somerset, England) transmitter
 | Google Streetview |  | Google map |  | Bing map |  | Google Earth |  | 51.237,-2.626 or 51°14'12"N 2°37'33"W |  | BA5 3LB |
The symbol shows the location of the Mendip (Somerset, England) transmitter which serves 720,000 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 Mendip (Somerset, England) mast?
Mendip transmitter - Mendip transmitter: Possible effect on TV reception week commencing 22/04/2024 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 Mendip 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 Mendip transmitter?
ITV West Country News (East) 0.9m homes 3.4%
from Bristol BS4 3HG, 23km north (11°)
to ITV West region - 61 masts.
All of lunch, weekend and 50% evening news is shared with West Country (West)
Are there any self-help relays?
| Cheddar | Transposer | 15 km E Weston-super-Mare | 1674 homes |
| Luccombe | Active deflector | 6 km w Minehead | 38 homes |
How will the Mendip (Somerset, England) transmission frequencies change over time?
| 1984-97 | 1997-98 | 1998-2010 | 2010-13 | 2013-18 | 2013-17 | 27 Feb 2018 | |||
| C/D E | E | E | C/D E | C/D E T | W T | W T | |||
| C30 | _local | ||||||||
| C32 | BBCA | ||||||||
| C33 | com7 | com7 | |||||||
| C34 | D3+4 | ||||||||
| C35 | com8 | com8 | |||||||
| C36 | ArqB | ||||||||
| C37 | C5waves | C5waves | |||||||
| C48 | SDN | SDN | SDN | SDN | |||||
| C49tv_off | BBCA | BBCA | |||||||
| C51tv_off | LBS | LBS | |||||||
| C52tv_off | ArqB | ArqB | ArqB | ||||||
| C54tv_off | C4waves | C4waves | C4waves | D3+4 | D3+4 | D3+4 | |||
| C55tv_off | com7tv_off | ||||||||
| C56tv_off | ArqA | ArqA | ArqA | COM8tv_off | |||||
| C58tv_off | BBC1waves | BBC1waves | BBC1waves | BBCB | BBCB | BBCB | |||
| C61 | ITVwaves | ITVwaves | ITVwaves | BBCA | |||||
| C64 | BBC2waves | BBC2waves | BBC2waves |
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 24 Mar 10 and 7 Apr 10.
How do the old analogue and currrent digital signal levels compare?
| Analogue 1-4 | 500kW | |
| Analogue 5 | (-6dB) 126kW | |
| SDN, ARQA, ARQB, BBCA, D3+4, BBCB | (-7dB) 100kW | |
| com7 | (-8.4dB) 72.4kW | |
| com8 | (-8.6dB) 69.1kW | |
| Mux 1*, Mux 2*, Mux A*, Mux B*, Mux C*, Mux D*, LBS | (-17dB) 10kW |
Which companies have run the Channel 3 services in the Mendip transmitter area
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Tuesday, 5 December 2023
C
Chris.SE12:22 AM
Peter Salmon:
Despite being predicted to get good reception in normal circumstances, you are most likely correct as your line of sight to Mendip is obscured by the local hills in any event.
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Thx for reply Chris.SE, my postcode is BA14 0EY, i did check the signal strength on affected channels, and there down alot from usual, there around 50% and bit error level like 3 to 7, usually there ok(strength 80 and no errors), so will just wait for them to be put on normal power, thx
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Christopher's: mapC's Freeview map terrainC's terrain plot wavesC's frequency data C's Freeview Detailed Coverage
Wednesday, 6 December 2023
C
Chris.SE12:27 AM
Christopher Sercombe:
Hi. Your postcode should have clear line of sight to Mendip and you shouldn't have any problems getting a good signal. The aerial should point at compass bearing 254 degrees, that's slightly W of WSW for your postcode, with the rods (or squashed Xs) horizontal.
That's on the assumption that you don't have any very local obstructions, large buildings, trees, scaffolding, other metal objects, etc. Such situations will be made worse if the aerial is low down . If in a loft, water tanks, metal flues, lead flashing, solar panels could all cause problems.
Have you had a postcard from Restore TV?
I put your postcode in here https://restoretv.uk/post…ure/ to check and it says Yes, you should have had one, but we know many cases where people haven't had them.
If there's a new/upgraded phone mast near you, it could be causing interference problems, cause desensitisation of your receiver tuner and give the sort of symptoms you see when the transmitter is on reduced power.
If you haven't got a filter, get in touch with them and request a free filter to see if that helps.
If you have a pre-amp/splitter to feed more than one TV, the filter should go before the amp.
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Chris.SE
Thankyou for reply, yes we have a really large tree literally in line with aerial right next to us, but its been there like 20 years, not really caused a problem, i did get a filter sent from restore tv last year, also my amplifier has a built in filter that is meant to do same job, i have had issues last 5 years on and off, but just been worse lately, i bought new aerial and cable the other month, but no difference really, whats mad is, some days/wee or so it can be perfect, thx for reply.
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C
Chris.SE12:08 PM
Christopher Sercombe:
The filter in your amplifier is probably not a "5G" 700MHz one, it'll more likely be for 4G LTE 800MHz.
You need the Filter from Restore TV. That will also clobber the 4G stuff.
I hope your new aerial was a Group K and the coax was double screened similar to CT100.
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S
Steve Donaldson5:40 PM
Christopher Sercombe: I see there are six properties in your postcode. Four are on the north side of the road and two on the south side.
The path to the transmitter is along the line of the road, or almost, meaning that aerials are directed along the apex. This likely rules out any possibility of mounting the aerial on the front or rear wall because it would have to point along the wall and the wall will therefore impact the signal.
Having looked at Google Street View photos and satellite images, the four houses on the north side do not appear to have any tree that could potentially cause difficulty. However, the two on the south side clearly do. If I had to guess, you live in one of these houses. There is not one shared chimney at the party wall on which the aerials are mounted. Rather, each has its own chimney half way along, hence one aerial is closer to the tree than the other. It still begs the question whether the immediate neighbour has any issue with reception too.
While the tree is fenced off from the pavement by metal railings, there is another wall between the ground it is on and the house immediately adjacent to it. Skipping back to the May 2009 Street View photo I see that where there are now railings there were concrete bollards then. The ground was trimmed grass and now it is overgrown. A check of the map on the local planning register has the area the tree is on coloured green, implying it is common/public land and not part of the house it is adjacent to.
If you are indeed in one of these two properties then you might be looking at the situation as a problem that may be impossible to overcome. After all, it is not within your power to prune the tree and the only way around it would be to mount the aerial on a very very tall pole, and even then the aerial would still be pointing through the canopy. You're snookered, basically.
I think there's a relatively easy answer: mount the aerial down your garden on the shed or other outbuilding such as the garage. At your location it would seem likely that reception at lower level may be good. Looking at the backs of the two houses from Sycamore Grove (on Street View) I can see over the wall. I can see that the property closest to the tree has a single storey extension on the rear. There is the question of whether it would be desirable to have an aerial on this both from aesthetic perspective and in terms of whether it would be possible to attach one. I'm not sure either way. Attaching an aerial to anything you have to consider the effect of the wind blowing on the aerial and mast -- it's not just a case of the weight of the mast and aerial on their own, there is wind-loading.
This then leaves the shed. I see both gardens have a shed at the end, both of which are alongside the fence. The cable could be run along the fence to the house. I would give some thought as to whether to use nailed cable cleats or some other method, such as some type of adhesive that will adhere to the surface it needs to stick to. Whether it is your fence or that of your neighbour may also have bearing on the approach. The other possibility is some form of conduit buried just under the soil alongside the fence line, although this will need appropriate waterproofing so it doesn't become filled with water. It's rather pointless feeding a length of cable through conduit to give it protection from the elements if you leave the ends open for rainwater to come in!
When affixing it to the shed, use wood screws that are long enough to go through the wall into one of the studs on the inside so as to give it strength. Use a proper wall bracket and pole, not a loft bracket and 90 degree pole as these are really meant only for inside a loft where there is no wind blowing.
ATV in Sheffield has some extensive information on its website (other suppliers are available):
Poles and masts A.T.V. Poles, Brackets, Clamps & Aerials
A log periodic has low wind-loading and is one of the least aesthetically intrusive TV aerial types:
Log Periodic aerials A.T.V. Poles, Brackets, Clamps & Aerials
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Steve Donaldson
Wow, what a awesome in depth post, thx very much, you gave me alot to think about, and yes you guess right, i live at the farthest house of the semi, one without the extension, we have the big shed at bottom of garden, the other house has a brick garage and shed, just for your info, that large tree is now almost twice as high and wide as it is on google and owned by the council, so the tree is going no where, now in winter our gardens swim in leaves from that tree, and we have asked council to lob and prune the tree, but no joy, i will look at doing something you said, thx alot for great post, cheers
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Thursday, 7 December 2023
C
Chris.SE6:25 AM
Christopher Sercombe:
Steve does periodically do a very thorough analysis of some of these situations. I did take a quick look and noted two trees that were potential problems if you lived in the "wrong" house, which is why I mentioned trees in my previous post. I didn't look in depth further as you'd originally mentioned reception was ok in normal circumstances, and it seemed as though the issue was only present with this current engineering.
The booster is fine BUT iirc earlier versions did not have the 5G filtering, so you need to confirm what is marked on the packaging or the booster. If you need to try additional 5G Filtering, as previously mentioned, it should be on the input side of the amp/booster.
The "problem" with that aerial, from such suppliers as Argos, is they don't say which version it is. Although some previous versions were CAI approved, they were also Wideband. Some later versions had 4G filtering and some versions were what's called by some as"bacofoil" aerials - easily damaged by winds and pigeons perching on them. You may only know from what it said on the packaging, and keep an eye on it for damage.
I certainly wouldn't be rushing to change anything, the aerial is high gain which you probably need because of the tree, albeit the highest gain is at the "wrong" end of the band - nearest/into the 700MHz band, hence the importance of the 5G filtering. You'll probably struggle to get as much gain from a standard log-periodic although Blake make a 56 element Group K which has high gain.
If problems were to continue after the engineering was completed then I'd look at the possibility of relocating the aerial first.
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Chris.SE
As with all your great posts, thx, i do apricate your help, aerial is in loft, not ideal, but should not get damaged, i will see how it goes after work finished on mendip transmitter.
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