“Efail Fach television relay station”的意思、由来-开放百科全书

词条

Efail Fach television relay station

释义

Channels listed by frequency
Analogue television 1980s - 12 August 2009 Analogue and digital television 12 August 2009 - 9 September 2009 Digital television 9 September 2009 - present 13 March 2013
References
External links

{{Infobox UK transmitter
|name = Efail Fach
|image =
|map = {{Location map+
| Wales Neath Port Talbot
| width = 250
| float = center
| caption =
| places ={{Location map~
| Wales Neath Port Talbot
| label = Efail Fach
| position =
| mark =
| coordinates = {{coord|51.648309|-3.755346|type:landmark_region:GB|display=inline}}

}}{{Location map~

| Wales Neath Port Talbot
| label = Kilvey Hill
| position =
| mark = Green pog.svg
| coordinates = {{coord|51.629167|-3.920278|type:landmark_region:GB|display=inline}}
}}
}}
|height = {{convert|15|m|ft|0}}
|gridref = SS786958
|built = 1980s
|demolished =
|collapsed =
|relay = Kilvey Hill
|BBC = BBC Wales
|ITV = ITV Wales
}}

The Efail Fach television relay station is sited on a hill west of the villages of Efail Fach, Cwm Pelenna and Tonmawr. It was originally built in the 1980s as a fill-in relay for UHF analogue colour television serving all of those settlements. It consists of a 15 m self-supporting lattice mast standing on a hill which is itself about 160 m above sea level. The transmissions are beamed to the east towards the Pelenna valley. The Efail Fach transmission station is owned and operated by Arqiva.

The "Transmission Gallery" site claims^[1] that the Efail Fach transmitter re-radiates the signal received off-air from Cilfrew television relay station near Neath, itself a repeater of Kilvey Hill at Swansea. However, Efail Fach used the same frequencies as Cilfrew in the analogue TV days, and shares two frequencies with Cilfrew in the digital TV era.

OFCOM claims^[2] that the site re-radiates Kilvey Hill directly. Efail Fach does indeed have a clear line-of-sight to Kilvey Hill (which is about 11.6 km away at a bearing of 259.5°).

When it came, the digital switchover process for Efail Fach duplicated the timing at the Kilvey Hill parent station, with the first stage taking place on Wednesday 12 August 2009 and the second stage was completed on Wednesday 9 September 2009, with the Kilvey Hill transmitter-group becoming the first in Wales to complete digital switchover. After the switchover process, analogue channels had ceased broadcasting permanently and the Freeview digital TV services were radiated at an ERP of 2 W each.^[3]

Channels listed by frequency

Analogue television

1980s - 12 August 2009

Efail Fach (being in Wales) transmitted the S4C variant of Channel 4.

{{no2Frequency	{{no2UHF	{{no2kW	{{no2Service
ch=39}}	39	0.008	BBC One Wales
ch=45}}	45	0.008	BBC Two Wales
ch=49}}	49	0.008	ITV1 Wales (HTV Wales until 2002)
ch=52}}	52	0.008	S4C

Analogue and digital television

12 August 2009 - 9 September 2009

The UK's digital switchover commenced at Kilvey Hill (and therefore at Efail Fach and all its other relays) on 12 August 2009. Analogue BBC Two Wales on channel 45 was first to close, and ITV1 Wales was moved from channel 49 to channel 45 for its last month of service. Channel 49 was replaced by the new digital BBC A mux which started up in 64-QAM and at full power (i.e. 2 W).

{{no2Frequency	{{no2UHF	{{no2kW	{{no2Service	{{no2System
ch=39}}	39	0.008	BBC One Wales	PAL System I
ch=45}}	45	0.008	ITV1 Wales	PAL System I
ch=49}}	49	0.002	BBC A	DVB-T
ch=52}}	52	0.008	S4C	PAL System I

Digital television

9 September 2009 - present

The remaining analogue TV services were closed down and the digital multiplexes took over on the original analogue channels' frequencies.

Frequency	UHF	kW	Operator
ch=45}}	45	0.002	Digital 3&4
ch=49}}	49	0.002	BBC A
ch=52}}	52	0.002	BBC B

13 March 2013

As a side-effect of frequency-changes elsewhere in the region to do with clearance of the 800 MHz band for 4G mobile phone use,^[4] Efail Fach's "BBC B" multiplex will have to be moved from channel 49 to channel 39.^[5]

{{Yes2Frequency	{{Yes2UHF	{{Yes2kW	{{Yes2Operator
ch=39}}	39	0.002	BBC A
ch=45}}	45	0.002	Digital 3&4
ch=52}}	52	0.002	BBC B

{{See also|List of digital terrestrial television channels (UK)}}

References

1. ^http://tx.mb21.co.uk/gallery/efail-fach.php
2. ^http://www.digitaluk.co.uk/transmitternetwork/tools__and__resources/almanac/installer_newsletters_transmitter_groups2009_pdfs/Installer_Newsletter_Kilvey_Hill__1_month_out_FINAL_24_July_09.pdf
3. ^{{cite web |url=http://www.ukfree.tv/txdetail.php?a=SS786958 |title=Freeview on Efail Fach TV transmitter |publisher=ukfree.tv |accessdate=2012-02-21}}
4. ^https://thenextweb.com/eu/2012/02/15/eu-states-must-allow-4g-internet-use-on-analogue-tv-spectrum-by-january-2013/
5. ^http://www.a516digital.com/2012/10/digital-uk-confirms-further-4g-retune.html

External links

The Transmission Gallery: Efail Fach

{{Transmitter sites in Wales}}{{Wenvoe UHF 625-line Transmitter Group}}{{Kilvey Hill UHF DVB Transmitter Group}}{{Television transmitters in the UK}}

2 : Transmitter sites in Wales|Wenvoe UHF 625-line Transmitter Group

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