View source for Mendip transmitting station

{{Short description|Broadcasting and telecommunications facility}}
{{More sources|date=March 2024}}
{{Use dmy dates|date=July 2019}}
{{Use British English|date=April 2022}}
{{Infobox UK Transmitter |
|name = Mendip
|image = Mendipmastjune2005.jpg 
|caption = The Mendip UHF television mast
|map_name = Somerset
|coordinates = {{coord|51.2370|-2.6253|type:landmark_region:GB|display=inline,title}}
|height = {{cvt|293|m}}
|gridref=ST564488
|built = 1967
|demolished = 
|collapsed = 
|BBC = [[BBC West]]
|ITV = {{plainlist|
* [[ITV West Country]]
* (formerly [[ITV Wales & West|ITV West]])
}}
|localtv = [[Local TV Bristol]]
}}

The '''Mendip transmitting station''' is a [[broadcasting]] and [[telecommunication]]s facility on the summit of [[Pen Hill]], part of the [[Mendip Hills]] range in Somerset, England, at {{convert|305|m|ft|0}} above sea level. The station is in [[St Cuthbert Out]] civil parish, approximately {{convert|2|mi|km}} north-east of [[Wells, Somerset|Wells]]. Its mast, {{Cvt|293|m}} high, was built in 1967 and is the tallest structure in [[South West England]]. The mast broadcasts digital television, FM analogue radio and DAB digital radio, and had broadcast analogue colour television from 1967 until 2010.

== Description ==
The station is owned and operated by [[Arqiva]] (which acquired National Grid Wireless, previously Crown Castle).

Until 2008 a [[glass-reinforced plastic]] aerial cylinder, containing the analogue television transmitting [[Antenna (radio)|antennas]], was mounted at the top of the mast, bringing the total height of the structure to {{convert|305|m|ft|0}}. With a mean height of {{convert|596|m|ft|0}} above sea level, these antennas were among the highest in the UK. They were removed in 2010, the antenna cylinder being replaced with a new antenna assembly, ready for [[Digital terrestrial television in the United Kingdom#Digital switchover|digital switchover]] later that year. The present assembly is slightly shorter than the previous cylinder, causing the overall mast height to be reduced from {{convert|305|m|ft|0}} to {{convert|293|m|ft|0}}.<ref>{{cite web|title=Mendip|url=https://www.thebigtower.com/live/Mendip/Index.htm|website=The Big Tower|access-date=6 April 2018}}</ref>

There are red [[aircraft warning lamps]] (six sets of two lights) on the mast, and two lights on top. The mast can be seen from as far away as [[Puriton]] during the day, and the aircraft warning lights make it visible at night from most of the [[Somerset Levels]] and from areas of South Wales, such as the high ground near the [[Wenvoe transmitting station]].{{Citation needed|date=November 2024}}

==Television==
Mendip was configured as a C/D group transmitter when it entered service with analogue [[PAL]] transmissions. In July 2007, [[Ofcom]] confirmed that it would remain a C/D group transmitter at [[Digital switchover dates in the United Kingdom|digital switchover]]. The mast broadcasts digital television over a large area of the west of England, including [[Somerset]], [[Wiltshire]], [[Bristol]], southern [[Gloucestershire]], and northern [[Dorset]]. Northern Gloucestershire – such as most of [[Cheltenham]] and [[Tewkesbury]] – is outside the coverage area, instead receiving signals from [[Ridge Hill transmitting station]] in Herefordshire.<ref>{{Cite web |date=2004-05-01 |title=Ridge Hill (County of Herefordshire, England) Full Freeview transmitter |url=https://ukfree.tv/transmitters/tv/Ridge_Hill |access-date=2024-03-26 |website=UK Free TV |language=en}}</ref>

Cardiff and other parts of southeast [[Wales]] were also able to receive the analogue TV transmissions from Mendip,{{cn|date=September 2025}} and many households used it in preference to the more local Wenvoe transmitter which carries the Wales variations of BBC One, BBC Two, and ITV. This was originally because the Wenvoe transmitter broadcast [[S4C]] (with programmes in Welsh and some prime-time English programmes from Channel 4 scheduled at much later times) rather than Channel 4 itself. Even after digital switchover when transmitters in Wales also began to broadcast Channel 4 in addition to S4C, some households continued with their preference for the West variations of BBC One, BBC Two, and ITV, and having Channel 4 (not S4C) as number 4 on the electronic programme guide.

Power on analogue transmissions was 500&nbsp;kW ([[Effective radiated power|ERP]]) for BBC 1, BBC2, HTV West, Channel 4, and 126&nbsp;kW (ERP) for Channel 5. The latter was transmitted outside of the original C/D grouping of the transmitter but most homes in reasonable signal areas for the C/D group could receive it with their C/D group aerial. All six digital multiplexes were transmitted at 10&nbsp;kW until switchover in 2010 when the power on the "BBC A", "BBC B/HD" and "D3&4" multiplexes was boosted to 100&nbsp;kW. In 2011, SDN was boosted to 50&nbsp;kW and in 2012 the remaining two Arqiva multiplexes were boosted to 50&nbsp;kW too.

In June 2019, as part of the 700MHz clearance programme, Mendip became K group (excluding muxes 7 and 8, which are due to be switched off between 2020 and 2022). This means that homes in poor signal areas which still have a C/D group aerial may have difficulty in receiving all multiplexes.{{cn|date=August 2025}}

Mendip's population coverage is around 1.5 million, although some homes in the immediate vicinity, such as those in [[Cheddar, Somerset|Cheddar]], are unable to receive a signal due to being in the shadow of the Mendip Hills and therefore depend on local relays.

==Radio==
Mendip broadcasts [[FM broadcasting|FM]] (analogue VHF) radio for [[BBC Radio Somerset]] and the Severn Estuary regional service [[Kiss 101]]. Mendip also transmits high power [[Digital Audio Broadcasting]] (DAB) signals for the [[Digital One]], Sound Digital and [[BBC National DAB]] multiplexes. An additional DAB multiplex, [[MuxCo Somerset]], was awarded a licence in 2008 to broadcast local and national services to Somerset, and began transmission in 2014.<ref>{{cite web|title=South West England and Wales|url=http://frequencyfinder.org.uk/DAB_SW_map1.pdf|publisher=Frequency Finder|access-date=23 August 2011|url-status=dead|archive-url=https://web.archive.org/web/20090219112854/http://frequencyfinder.org.uk/DAB_SW_map1.pdf|archive-date=19 February 2009}}</ref> After the closure of the Severn Estuary digital radio multiplex, the equipment from Mendip was reused to improve coverage on the Welsh coastline for the Cardiff & Newport, now South East Wales, multiplex.<ref name="auto1">{{Cite web |date=January 2015 |title=DAB Coverage Plan: South East Wales Local Multiplex |url=https://www.ofcom.org.uk/siteassets/resources/documents/tv-radio-and-on-demand/dab-coverage-plans/south_east_wales_dab_coverage_plan_final_report_jan15.pdf?v=335045 |website=Ofcom}}</ref><ref>{{Cite web |date=2022-05-09 |title=Technical parameters for broadcast radio transmitters |url=https://www.ofcom.org.uk/spectrum/information/radio-tech-parameters |access-date=2023-04-17 |website=Ofcom |language=en}}</ref>

==Output==

===Radio===

====Analogue====
{| class="wikitable sortable"
!Frequency
!kW<ref name="auto">Radio Listeners Guide 2010</ref>
!Service
!Notes
|-
|95.5&nbsp;[[MHz]]
|5
|[[BBC Radio Somerset]]
|
|-
|101.0&nbsp;MHz
|40
|[[Hits Radio]]
|Directional antenna towards South Wales<ref>{{Cite web |title=Photo of effective power map |url=https://fmscan.org/power.png.php?i=2801161}}</ref>
|-
|102.6&nbsp;MHz
|4
|[[Heart West]]
|
|}

====Digital====
{| class="wikitable sortable"
!Frequency
!Block
!kW<ref name="auto"/>
!Operator
!Notes
|-
|211.648&nbsp;MHz
|10B
|1.2
|[[MuxCo Somerset]]
|
|-
|216.928&nbsp;MHz
|11A
|
|[[Sound_Digital|Sound Digital Limited]]
|
|-
|222.064&nbsp;MHz
|11D
|5
|[[Digital One]]
|
|-
|225.648&nbsp;MHz
|12B
|5
|[[BBC National DAB]]
|
|-
|227.360 MHz
|12C
|1.5<ref name="auto1"/>
|South East Wales
|For improved coverage on the Welsh coastline{{cn|date=September 2025}}
|}

===Television===

====Analogue====

=====1 December 1969 – 11 May 1970=====
{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Service
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|}

=====11 May 1970 – 30 May 1970=====
{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Service
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|}

=====30 May 1970 – 2 November 1982=====
{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Service
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|-
|{{UK System I|ch=61}}
|61
|500
|[[ITV Wales & West|HTV West]]
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|}

=====2 November 1982 – 30 March 1997=====
{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Service
|-
|{{UK System I|ch=54}}
|54
|500
|[[Channel 4]]
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|-
|{{UK System I|ch=61}}
|61
|500
|[[ITV Wales & West|HTV West]]
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|}

=====30 March 1997 – 15 November 1998=====
{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Service
|-
|{{UK System I|ch=37}}
|37
|126
|[[Channel 5 (British TV channel)|Channel 5]]
|-
|{{UK System I|ch=54}}
|54
|500
|[[Channel 4]]
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|-
|{{UK System I|ch=61}}
|61
|500
|[[ITV Wales & West|HTV West]]
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|}

====Analogue and digital====

=====15 November 1998 – 24 March 2010=====
Digital terrestrial television was first transmitted from the Mendip mast from 15 November 1998 using the frequency gaps between the analogue TV broadcasts. To limit interference to the analogue transmissions, power output on the digital multiplexes was low.

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK System I|ch=37}}
|37
|126
|[[Channel 5 (British TV channel)|Channel 5]]
|[[PAL]] System I
|-
|{{UK System I|ch=54}}
|54
|500
|[[Channel 4]]
|PAL System I
|-
|{{UK DVB-T|ch=55|off=pos}}
|55+
|10
|[[Digital 3&4]] (Mux 2)
|[[DVB-T]]
|-
|{{UK DVB-T|ch=56|off=pos}}
|56+
|10
|[[Arqiva]] (Mux C)
|DVB-T
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|PAL System I
|-
|{{UK DVB-T|ch=59|off=pos}}
|59+
|10
|[[BBC]] (Mux 1)
|DVB-T
|-
|{{UK System I|ch=61}}
|61
|500
|HTV West
|PAL System I
|-
|{{UK DVB-T|ch=62|off=pos}}
|62+
|10
|[[S4C Digital Networks|SDN]] (Mux A)
|DVB-T
|-
|{{UK System I|ch=64}}
|64
|500
|[[BBC Two|BBC2 West]]
|PAL System I
|-
|{{UK DVB-T|ch=65|off=pos}}
|65+
|10
|BBC (Mux B)
|DVB-T
|-
|{{UK DVB-T|ch=67}}
|67
|10
|Arqiva (Mux D)
|DVB-T
|}

=====24 March 2010 – 7 April 2010=====
On 24 March 2010 BBC2 was switched off on UHF 64 and HTV West was switched from UHF 61 for its final weeks of service. Multiplex 1 on UHF 59+ was closed and replaced by BBC A on UHF 61 (which had just been vacated by analogue HTV West). BBC A was transmitted at full power (100&nbsp;kW) and in 64QAM, 8k carriers mode from the start.

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK System I|ch=37}}
|37
|126
|[[Channel 5 (British TV channel)|Channel 5]]
|[[PAL]] System I
|-
|{{UK System I|ch=54}}
|54
|500
|[[Channel 4]]
|PAL System I
|-
|{{UK DVB-T|ch=55|off=pos}}
|55+
|10
|[[Digital 3&4]] (Mux 2)
|[[DVB-T]]
|-
|{{UK DVB-T|ch=56|off=pos}}
|56+
|10
|[[Arqiva]] (Mux C)
|DVB-T
|-
|{{UK System I|ch=58}}
|58
|500
|[[BBC One|BBC1 West]]
|PAL System I
|-
|{{UK DVB-T|ch=61}}
|61
|100
|[[BBC]] A
|DVB-T
|-
|{{UK DVB-T|ch=62|off=pos}}
|62+
|10
|[[S4C Digital Networks|SDN]] (Mux A)
|DVB-T
|-
|{{UK System I|ch=64}}
|64
|500
|[[ITV Wales & West|HTV West]]
|PAL System I
|-
|{{UK DVB-T|ch=65|off=pos}}
|65+
|10
|BBC (Mux B)
|DVB-T
|-
|{{UK DVB-T|ch=67}}
|67
|10
|Arqiva (Mux D)
|DVB-T
|}

====Digital====

=====7 April 2010 – 28 September 2011=====
Following the completion of analogue TV shutdown on 7 April 2010, Mendip transmitted all of its higher powered multiplexes at 100&nbsp;kW. From this date until the second-stage switchover of 28 September 2011 the frequency allocation was:

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|[[DVB-T]]
|-
|{{UK DVB-T|ch=56|off=pos}}
|56+
|10
|[[Arqiva]] A
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|-
|{{UK DVB-T|ch=61}}
|61
|100
|BBC A
|DVB-T
|-
|{{UK DVB-T|ch=62|off=pos}}
|62+
|10
|[[S4C Digital Networks|SDN]]
|DVB-T
|-
|{{UK DVB-T|ch=67}}
|67
|26
|Arqiva B
|DVB-T
|}

=====28 September 2011 – 28 March 2012=====
With the completion of digital switchover at Oxford, all multiplexes could be moved to their final channel allocations with the exception of Arqiva A. SDN increased to half its full power output (50&nbsp;kW).

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=48}}
|48
|50
|[[S4C Digital Networks|SDN]]
|[[DVB-T]]
|-
|{{UK DVB-T|ch=52}}
|52
|25.7
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|-
|{{UK DVB-T|ch=61}}
|61
|100
|BBC A
|DVB-T
|-
|{{UK DVB-T|ch=67}}
|67
|26
|Arqiva A
|DVB-T
|}

=====28 March 2012 – 26 March 2013=====
On 28 March 2012 Arqiva A moved to its final channel allocation at UHF 56, after the completion of digital switchover at Salisbury. Arqiva A and B and SDN also increased to full power (100&nbsp;kW) on this date.<ref>{{Cite web|url=http://www.digitaluk.co.uk/transmitternetwork/tools__and__resources/almanac/special_editions/Special_edition-installers_Mendip_retune_event_March2012_Final_rev23March.pdf|title = Corporate| date=7 February 2023 }}</ref>

{| class="wikitable sortable"
!Frequency
!UHF
!kW
!Operator
!System
|-
|{{UK DVB-T|ch=48}}
|48
|100
|[[S4C Digital Networks|SDN]]
|[[DVB-T]]
|-
|{{UK DVB-T|ch=52}}
|52
|100
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=56}}
|56
|100
|Arqiva A
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|-
|{{UK DVB-T|ch=61}}
|61
|100
|BBC A
|DVB-T
|}

=====27 March 2013 – 27 February 2018=====
BBC A moved from UHF 61 to UHF 49 to allow for the clearance of the 800&nbsp;MHz band for 4G LTE mobile services.<ref>{{cite web | url=https://ukfree.tv/article/1107051940/2013_postswitchover_changes_to_Freeview_transmissi | title=2013 - post-switchover changes to Freeview transmission frequencies | publisher=ukfree.tv | date=13 January 2012 | first=Brian | last=Butterworth | access-date=22 July 2019 }}</ref><ref>{{Cite web|url=http://www.digitaluk.co.uk/when_do_i_switch/west|title=Corporate|date=7 February 2023 }}</ref>

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=48}}
|48
|100
|[[S4C Digital Networks|SDN]]
|[[DVB-T]]
|-
|-
|{{UK DVB-T|ch=49}}
|49
|100
|BBC A
|DVB-T
|-
|{{UK DVB-T|ch=52}}
|52
|100
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=56}}
|56
|100
|Arqiva A
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|}

===== 27 February 2018 -  4 April 2019 =====
Arqiva A has moved from UHF 56 to UHF 33 for the start of the 700MHz clearance programme at Mendip. 

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=33}}
|33
|100
|Arqiva A
|[[DVB-T]]
|-
|{{UK DVB-T|ch=48}}
|48
|100
|[[S4C Digital Networks|SDN]]
|DVB-T
|-
|{{UK DVB-T|ch=49}}
|49
|100
|BBC A
|DVB-T
|-
|{{UK DVB-T|ch=52}}
|52
|100
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|}

===== 4 April 2019 – 5 June 2019 =====
BBC A has moved from UHF 49 to UHF 32 as part of the 700MHz clearance programme at Mendip. 

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=32}}
|32
|100
|BBC A
|[[DVB-T]]
|-
|{{UK DVB-T|ch=33}}
|33
|100
|Arqiva A
|DVB-T
|-
|{{UK DVB-T|ch=48}}
|48
|100
|[[S4C Digital Networks|SDN]]
|DVB-T
|-
|{{UK DVB-T|ch=52}}
|52
|100
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=54}}
|54
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=58}}
|58
|100
|[[BBC]] B
|[[DVB-T2]]
|}

===== 5 June 2019 - Present =====
Digital 3&4 has moved from UHF 54 to UHF 34, and BBC B have moved as well from UHF 58 to UHF 35 as part of the 700MHz clearance programme at Mendip. Many Welsh residents also prefer Mendip's service to the Wenvoe service as it provides a stronger signal to the coastline and areas in the shadow of the Wenvoe mast. 

{| class="wikitable sortable"
!{{no2}}Frequency
!{{no2}}UHF
!{{no2}}kW
!{{no2}}Operator
!{{no2}}System
|-
|{{UK DVB-T|ch=32}}
|32
|100
|BBC A
|[[DVB-T]]
|-
|{{UK DVB-T|ch=33}}
|33
|100
|Arqiva A
|DVB-T
|-
|{{UK DVB-T|ch=34}}
|34
|100
|[[Digital 3&4]]
|DVB-T
|-
|{{UK DVB-T|ch=35}}
|35
|100
|[[BBC]] B
|[[DVB-T2]]
|-
|{{UK DVB-T|ch=36}}
|36
|100
|[[Arqiva]] B
|DVB-T
|-
|{{UK DVB-T|ch=48}}
|48
|100
|[[S4C Digital Networks|SDN]]
|DVB-T
|}

==See also==
*[[List of masts]]
*[[List of radio stations in the United Kingdom]]
*[[List of tallest buildings and structures in Great Britain]]

==References==
{{Reflist}}

==External links==
{{Commons category}}
*[http://skyscraperpage.com/cities/?buildingID=19269: Entry at skyscraperpage.com]
*[http://www.thebigtower.com/live/Mendip/Index.htm Mendip Transmitter at thebigtower.com]
*[https://tx.mb21.co.uk/gallery/gallerypage.php?txid=620 The Transmission Gallery - Mendip]

{{Television transmitters in the UK}}

[[Category:Buildings and structures in Mendip District]]
[[Category:Radio masts and towers in Europe]]
[[Category:Transmitter sites in England]]
[[Category:Mendip Hills]]