kids encyclopedia robot

Rowridge transmitting station facts for kids

Kids Encyclopedia Facts
Quick facts for kids
Rowridge
Rowridge from entrance gate 200704270010.jpg
The Rowridge transmitting station
Rowridge transmitting station is located in Isle of Wight
Rowridge transmitting station
Location in Isle of Wight
Mast height 149.6 metres (491 ft)
Coordinates 50°40′35″N 1°22′07″W / 50.676389°N 1.368611°W / 50.676389; -1.368611
Grid reference SZ447865
BBC region BBC South
ITV region Southern (1969–1981)
TVS (1982–1992)
ITV Meridian (1993–present)
Local TV service That's Solent

The Rowridge transmitting station is a facility for FM radio and television transmission at Rowridge on the Isle of Wight in southern England.

It currently has a 172 metres (564 ft) tall guyed mast, owned and operated by Arqiva (previously National Grid Wireless). There is a smaller tower on the site belonging to British Telecom. Prior to Digital Switchover (DSO) the station broadcast with a power of 250 kW (ERP) for FM radio, 500 kW for analogue television, and 20 kW for digital television. In July 2007, Ofcom confirmed that Rowridge would remain an A Group transmitter at Digital switchover; the digital television transmission signal was then boosted to 200 kW. From March 2018 MUXES 7 & 8 moved out of the A group to channels 55 & 56 (see graph), though these are due to be turned off between 2020 and 2022.

Rowridge is one of only two main transmitters (the other is the rather smaller transmitter of Rosneath in Scotland) to broadcast its output on both horizontal and vertical polarities. Only the main 6 MUXES are transmitted in vertical polarity. The reason for this dual polarity transmission is to give a second option to those experiencing co-channel interference from transmitters on the continent.

Analogue Channel 5 was not transmitted from Rowridge but was broadcast (at 10 kW) from Fawley Power Station, with the antenna located on the main chimney. Transmissions all fitted within the A group and were horizontally polarised. On 25 March 2009, Channel 5's analogue signal was turned off from Fawley Power Station, due to the digital switchover in the neighbouring Westcountry region.

Population coverage for the main four analogue channels was about 1.75 million.

History

Rowridge mast, IW, UK

The station was first built to provide BBC 405-line television coverage for an area including Southampton, Portsmouth, Bournemouth, Chichester, Brighton, Winchester and Salisbury. Sites on the mainland and the Isle of Wight were considered, and three were tested by BBC Research Department. A temporary 200 ft lattice mast was built with a main antenna at 175 ft and a reserve antenna lower down. These aerials were directional to enhance the signal northwards and reduce unwanted coverage to the south.

The service opened on 12 November 1954, bringing television to the area for the first time.

A programme feed was obtained via a Post Office radio link, using refurbished equipment that provided the original picture feed for the Wenvoe Transmitter on the British Telecom Microwave Network. A site for this near Alton, Hampshire was acquired and named after a nearby pub: Golden Pot. Here the TV signal from Alexandra Palace was picked up and relayed via a one-hop 4 GHz microwave link to Rowridge. This was brought into service on 18 October 1954. Later, the microwave link ran from the Museum telephone exchange in London to Rowridge, using Golden Pot as an intermediate site.

In 1965 the UHF antenna was added making the total height of the structure 149.6 metres (491 ft). This addition allowed Rowridge to radiate the PAL 625-line transmission that allowed broadcasts in colour and eventually stereo sound, using NICAM.

On 25 March 2009, Channel 5's analogue signal was turned off from Fawley Power Station. Later on in the day, "existing digital terrestrial TV services moved to new frequencies", due to the digital switchover happening in the region in 2012.

Arqiva applied for planning permission to replace the existing 150m (492') mast with one 187m (614') high on 22 May 2009.

Channels listed by frequency

Analogue radio

Frequency kW Service
88.5 MHz 250 BBC Radio 2
90.7 MHz 250 BBC Radio 3
92.9 MHz 250 BBC Radio 4
96.1 MHz 10 BBC Radio Solent
98.2 MHz 250 BBC Radio 1
100.3 MHz 125 Classic FM

Digital radio

Frequency Block kW Operator
225.648 MHz 12B 5 BBC National DAB

Analogue television

12 November 1954 – 15 January 1966

Frequency VHF kW Service
56.75 MHz 3 100 BBC1

15 January 1966 – 13 December 1969

Frequency VHF UHF kW Service
56.75 MHz 3 — 100 BBC1
495.25 MHz — 24 500 BBC2

13 December 1969 – 27 December 1969

Frequency VHF UHF kW Service
56.75 MHz 3 — 100 BBC1
495.25 MHz — 24 500 BBC2
519.25 MHz — 27 500 Southern

27 December 1969 – 4 December 1982

Frequency VHF UHF kW Service
56.75 MHz 3 100 BBC1
495.25 MHz — 24 500 BBC2
519.25 MHz — 27 500 TVS (Southern until 1982)
551.25 MHz — 31 500 BBC1

4 December 1982 – 3 January 1985

Frequency VHF UHF kW Service
56.75 MHz 3 — 100 BBC1
471.25 MHz — 21 500 Channel 4
495.25 MHz — 24 500 BBC2
519.25 MHz — 27 500 TVS
551.25 MHz — 31 500 BBC1

3 January 1985 – 15 November 1998

Frequency UHF kW Service
471.25 MHz 21 500 Channel 4
495.25 MHz 24 500 BBC Two
519.25 MHz 27 500 Meridian (TVS until 1993)
551.25 MHz 31 500 BBC One

Analogue and digital television

15 November 1998 – 31 October 2002

Frequency UHF kW Service System
471.25 MHz 21 500 Channel 4 PAL System I
489.833 MHz 23- 20 BBC (Mux 1) DVB-T
495.25 MHz 24 500 BBC Two PAL System I
513.833 MHz 26- 20 Arqiva (Mux C) DVB-T
519.25 MHz 27 500 ITV1 (Meridian until 2002) PAL System I
530.000 MHz 28 20 Digital 3&4 (Mux 2) DVB-T
546.000 MHz 30 20 SDN (Mux A) DVB-T
551.25 MHz 31 500 BBC One PAL System I
562.166 MHz 32+ 20 BBC (Mux B) DVB-T
570.166 MHz 33+ 20 Arqiva (Mux D) DVB-T

31 October 2002 – 24 May 2007

Frequency UHF kW Service System
471.25 MHz 21 500 Channel 4 PAL System I
489.833 MHz 23- 20 BBC (Mux 1) DVB-T
495.25 MHz 24 500 BBC Two PAL System I
513.833 MHz 26- 20 Arqiva (Mux C) DVB-T
519.25 MHz 27 500 ITV1 PAL System I
530.000 MHz 28 20 Digital 3&4 (Mux 2) DVB-T
546.000 MHz 30 20 SDN (Mux A) DVB-T
551.25 MHz 31 500 BBC One PAL System I
562.166 MHz 32+ 20 BBC (Mux B) DVB-T
570.166 MHz 33+ 20 Arqiva (Mux D) DVB-T
735.25 MHz 54 2 Solent TV PAL System I

24 May 2007 – 25 March 2009

Frequency UHF kW Service System
471.25 MHz 21 500 Channel 4 PAL System I
489.833 MHz 23- 20 BBC (Mux 1) DVB-T
495.25 MHz 24 500 BBC Two PAL System I
513.833 MHz 26- 20 Arqiva (Mux C) DVB-T
519.25 MHz 27 500 ITV1 PAL System I
530.000 MHz 28 20 Digital 3&4 (Mux 2) DVB-T
546.000 MHz 30 20 SDN (Mux A) DVB-T
551.25 MHz 31 500 BBC One PAL System I
562.166 MHz 32+ 20 BBC (Mux B) DVB-T
570.166 MHz 33+ 20 Arqiva (Mux D) DVB-T

25 March 2009 – 7 March 2012

Frequency UHF kW Service System
471.25 MHz 21 500 Channel 4 PAL System I
495.25 MHz 24 500 BBC Two PAL System I
519.25 MHz 27 500 ITV1 PAL System I
530.166 MHz 28+ 20 BBC (Mux B) DVB-T
545.833 MHz 30- 20 SDN (Mux A) DVB-T
551.25 MHz 31 500 BBC One PAL System I
562.166 MHz 32+ 20 Digital 3&4 (Mux 2) DVB-T
570.166 MHz 33+ 20 Arqiva (Mux D) DVB-T
578.000 MHz 34 20 BBC (Mux 1) DVB-T
602.166 MHz 37+ 20 Arqiva (Mux C) DVB-T

7 March 2012 – 21 March 2012

Frequency UHF kW Service System
H V
471.25 MHz 21 500 — Channel 4 PAL System I
498.000 MHz 24 200 200 BBC A DVB-T
519.25 MHz 27 500 — ITV1 PAL System I
530.166 MHz 28+ 20 — BBC (Mux B) DVB-T
545.833 MHz 30- 20 — SDN (Mux A) DVB-T
551.25 MHz 31 500 — BBC One PAL System I
562.166 MHz 32+ 20 — Digital 3&4 (Mux 2) DVB-T
570.166 MHz 33+ 20 — Arqiva (Mux D) DVB-T
602.166 MHz 37+ 20 — Arqiva (Mux C) DVB-T

Digital television

21 March 2012 – 18 April 2012

Frequency UHF kW Operator System
H V
474.166 MHz 21+ 200 200 BBC B DVB-T2
498.000 MHz 24 200 200 BBC A DVB-T
522.000 MHz 27 200 200 Digital 3&4 DVB-T
545.833 MHz 30- 50 — SDN DVB-T
570.166 MHz 33+ 50 — Arqiva B DVB-T
602.166 MHz 37+ 50 — Arqiva A DVB-T

18 April 2012 – present

The commercial multiplexes were situated on their pre-DSO frequencies until 18 April 2012, when they started transmitting at vertical polarisation.

Frequency UHF kW Operator System
H V
474.166 MHz 21+ 200 200 BBC B DVB-T2
482.166 MHz 22+ 50 200 Arqiva A DVB-T
498.000 MHz 24 200 200 BBC A DVB-T
506.000 MHz 25 50 200 SDN DVB-T
522.000 MHz 27 200 200 Digital 3&4 DVB-T
530.000 MHz 28 50 200 Arqiva B DVB-T
602.000 MHz 37 10 - Local Multiplex DVB-T
kids search engine
All content from Kiddle encyclopedia articles (including the article images and facts) can be freely used under Attribution-ShareAlike license, unless stated otherwise. Cite this article:
Rowridge transmitting station Facts for Kids. Kiddle Encyclopedia.