thebigtower


selkirk

 


THE SELKIRK TRANSMITTER is the UHF and DAB main station that serves the majority of the Scottish Border area.

Sited on Lindean Moor towards the east of Selkirk town centre, this former ITV 405-line VHF site shares the vicinity with the former BBC 405-line equivalent at Ashkirk (now the area BBC FM transmitter), although unlike most other examples of adjacent siting the Selkirk transmitter came into operation before the BBC counterpart.

 

UHF COVERAGE

Selkirk serves a relatively small radius of approximately thirty miles extending principally towards the north-eastern coastline. This encompasses the main populated towns within the area although all of these (Galashiels, Hawick, Jedburgh) are supported by Selkirk-dependent relays.

The Berwick-upon-Tweed relay, formerly a dependent of Selkirk, is now fed by the Chatton main station in Northumberland.  


Aerials>  Station Images 740x420 or 930x550 pixels>  Supersize Images>  UHF Coverage Maps


 


DIGITAL SWITCHOVER

The Selkirk transmitter is notable for being the first UHF main station in the United Kingdom to complete the Digital Switchover process, the two stages of the procedure taking place as follows -

Stage 1 (DSO1) 6 November 2008
BBC Two analogue (Channel 62) switched off and the first BBC multiplex - BBCA (PSB1) launched.

Stage 2 (DSO2) 20 November 2008
All other analogue and low powered digital services ceased broadcasting permanently and the high powered digital multiplexes launched.

Full switchover in the Border area (the first to complete this in the UK) was achieved when the region's primary main station at Caldbeck (and associated relays) completed the process on 22 July 2009.  This completion date was later than original scheduled due mainly to the delays associated with the construction of the new mast at Caldbeck.

TRANSMISSION STRUCTURE

Selkirk transmissions are carried on a 229.8 metre (754-ft) square cross-section lattice stayed mast.  With the inclusion of the main UHF aerial mounted above the structure, the overall height is 238.8 Metres (783-ft).

It is unique for being the only lattice stayed-mast of ITA-origin to feature a square cross-section.  The adjacent mast at Ashkirk is coincidentally the only 228 metre (750-ft) mast of BBC origin to utilise a square cross-section design.

The Selkirk mast was previously used at the Black Hill station.  (See STATION HISTORY below).


 

 

 

 

 

 

 

 

 

 

 

 

 

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Aerials>  Station Images 740x420 or 930x550 pixels>  Supersize Images>  UHF Coverage Maps


STATION HISTORY

VHF

Selkirk was built by the Independent Television Authority (ITA) as the second of two stations designed to provide ITV coverage to the Border Television region on the original 405-line VHF Band III system.

The primary station was sited in the south-west of the region at Caldbeck and served the main areas of population in and around the city of Carlisle, plus parts of Dumfries and Galloway.  A second station was however needed to link these areas with the more remote sectors in the north-east of the region.

Being designated a relay of Caldbeck, it was decided to construct Selkirk as an unattended remotely-controlled satellite station, the first such installation to be built by the ITA, receiving broadcast feed directly from Caldbeck and then rebroadcasting the signal on a different channel.

Allocated VHF Channel 13, the Selkirk station was equipped with two vision transmitters both rated at 0.5 kilowatts and two sound transmitters both rated at 0.125 kilowatts, the secondary transmitters being redundancy provision as part of the specification for unattended operation.  The directional aerial would deliver a maximum Effective Radiated Power (ERP) of 25 kilowatts (vision) beamed mainly towards Berwick-upon-Tweed on the east coast.

To carry the transmissions, the ITA hastily re-deployed the 229 metre (750-ft mast) that had only recently been dismantled at Black Hill, having been superceded there by a taller structure.  Even though completion of the Caldbeck mast had also suffered delays, the provision of the Selkirk mast at such short notice meant that the station would be unable to commence operation from the same date as it's parent.

Regular service from Selkirk commenced on 1 December 1961, exactly three months after the inauguration of Border Television from the Caldbeck transmitter.  The estimated population coverage from Selkirk was 71,000 within the primary service area with fringe reception increasing this to approximately 97,000.

UHF

Selkirk commenced UHF-Colour transmission in 1972, upgrading to main station status in the process.  The coverage achieved under VHF was more or less matched under UHF by doubling the station's Effective Radiated Power to 50 kilowatts (vision).


 

 

 

 

 

 

 

Aerials

 

Station Images 740x420 or 930x550 pixels

 

UHF Coverage Maps

 

 

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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SITE INFORMATION


Location:

Lindean Moor, Selkirk, Scottish Borders

Grid Reference:

NT500294

Landlord:

Arqiva (Legacy: ITA/IBA/NTL)

Ground Height:

288.0m

BBC Region:

Scotland

Mast Height:

229.8m

ITV Region:

Border

Aerial Height (*):

519.0m

 

UHF Tx Number:

16100

(*) UHF aerial height above sea level (a.o.d)   

 

 


 CURRENT TRANSMISSIONS

Digital Television 

 

 

 

Analogue Radio (FM)

 

 

 

 

 

 

 

 

 

Service

: Ch/Polarisation/e.r.p

 

 

 Service:

(MHz)

(e.r.p)

PSB1

: 50 / H / 10kW  

 

 

Classic FM:

100.9

10kW

PSB2

: 59 / H / 10kW  

 

 

Radio Borders:

96.8

5kW

PSB3

: 55 / H / 10kW  

 

    BBC National Radio transmitted from Ashkirk

COM4

: 57 / H / 5kW 

 

 

COM5

: 53 / H / 5kW 

Digital Radio (DAB)

COM6

: 60 / H / 5kW

 

 

 

 

 

 

 

 

 

 

BBC National (Block 12B)

 

 

 

 

 

Digital One (Block 12A)

 

 

 

 

 

 

CEASED TRANSMISSIONS

(Shutdown completed 20 November 2008)

Analogue Television 

 

 

 

Digital Television

 

 

 

 

 

 

 

 

 

Service

  Ch/Polar/e.r.p

 

 

 

 

Service

 Ch/Polar/e.r.p

BBC1

: 55 / H / 50kW

 

 

 

 

Mux1

: 53 / H / 3.0kW

BBC2

: 62 / H / 50kW  

 

 

 

 

Mux2

: 67 / H / 3.0kW

ITV1

: 59 / H / 50kW 

 

 

 

 

MuxA

: 60 / H / 3.0kW

Ch4

: 65 / H / 50kW

 

 

 

 

MuxB

: 63 / H / 3.0kW

Ch5

: 52 / H / 50kW

 

 

 

 

MuxC

: 66 / H / 0.5kW

 

 

 

 

 

 

 

MuxD

: 56 / H / 0.5kW

 

 

 

 

 

 

 

 

 


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