 | |
  Knock More transmitting station (Moray) | |
| Location | nearBoharm,Moray |
|---|---|
| Mast height | 113 metres (371 ft) |
| Coordinates | 57°31′56″N3°08′06″W / 57.532332°N 3.135127°W /57.532332; -3.135127 |
| Grid reference | NJ322497 |
| BBC region | BBC Scotland |
| ITV region | STV North |
TheKnock More transmitting station (sometimes spelled "Knockmore") is a broadcasting facility, located at Knock More,[1] to east of the parish ofBoharm,Scotland, inMoray (grid referenceNJ322497). It is aguyed steel lattice mast which stands 113 metres (371 ft) high. The mast is located on elevated ground which is about 355 m above sea level,[2] and is betweenElgin andKeith. It was built by theIndependent Broadcasting Authority (IBA) to improve and extend UHF television coverage in north east Scotland, and is now owned and operated byArqiva.[3]
Knock More broadcasts to an area of Scotland which lies between the transmission areas of theDurris andRosemarkie stations,[4] primarily in theMoray region ofScotland. There is good reception of Knock More inBuckie, Elgin,Dufftown, Keith,Lhanbryde andLossiemouth. TheRumster Forest station also provides an overlap and alternative television signal along the coastal area betweenBurghead andBanff. Across theMoray Firth, reception of Knock More is also possible in coastal locations fromBalintore andBrora as far north asLybster.[5]
The ITU conference held in Stockholm, Sweden in 1961[6] led to the planning of the UHF television broadcasting network in the United Kingdom.[7] A high power UHF television transmitter was allocated for 625-line colour transmissions close to Banff, with the broadcasting channels 23/26/29/33 broadcasting at 100 kW effective radiated power (erp).
The station opened on 28 October 1974[8] broadcasting the BBC and ITV colour 625-line television channels on UHF band IV, using thePAL system, with horizontal polarisation.
| Frequency | UHF | kW | Service |
|---|---|---|---|
| 487.25 MHz | 23 | 100 | ITV Grampian |
| 511.25 MHz | 26 | 100 | BBC2 |
| 567.25 MHz | 33 | 100 | BBC1 |
Previously, 405-line television (broadcasting on the VHF bands I and III) had been available for many viewers from neighbouring transmitters at Meldrum and Rosemarkie (BBC)[9] and Durris,Mounteagle and Rumster Forest (ITV Grampian).
Programmes fromChannel 4 opened on UHF channel 29 in April 1984, withBBC Radio broadcasts on VHF band II commencing from October 1984.[10]
Knock More also broadcast its UHF 625-line colour television programmes on alternative frequencies (UHF channels 66/55/59/62) in a south-westerly direction to provide a better source for the television relay atGrantown. The Grantown relay is located on high ground, and two of the incoming programme sources from Knock More (ITV on ch23 and BBC2 on ch26) would have experiencedadjacent-channel interference from Rumster Forest (which broadcast on ch24 and ch27).
InterimDigital terrestrial television opened from 15 November 1999 at Knock More using channels 34, 30, 53, 60, and 56. Knock More had been considered a "group A" transmitter (UHF channels 21–34, Band IV). Three of the new digital multiplexes were in the upper part of Band V, which would have required some viewers to replace their aerials with a wideband[11] television aerial covering channels 21–68.
Fulldigital switchover completed on 22 September 2010, with the public service broadcast multiplexes using UHF channels 23, 26, and 29, and the commercial multiplexes on 53, 57, and 60.
The 700 MHz clearance event[12] in 2017 meant the commercial multiplexes were required to vacate their part of the television broadcasting spectrum, and as a result of this, a retune for viewers was required.
As of 2023, Knock More broadcasts digital terrestrial television on the following UHF frequencies[13]
| Frequency | UHF | kW | Multiplex | System |
|---|---|---|---|---|
| 538.000 MHz | 29 | 20 | BBC B | DVB-T2 |
| 554.000 MHz | 31 | 20 | BBC A | DVB-T |
| 570.000 MHz | 33 | 10 | SDN | DVB-T |
| 594.000 MHz | 36 | 10 | Arqiva A | DVB-T |
| 602.000 MHz | 37 | 20 | Digital 3&4 | DVB-T |
| 690.000 MHz | 48 | 10 | Arqiva B | DVB-T |
| Frequency | kW | Service |
|---|---|---|
| 88.2 MHz | 20 | BBC Radio 2 |
| 90.4 MHz | 20 | BBC Radio 3 |
| 92.6 MHz | 20 | BBC Radio Scotland |
| 94.8 MHz | 20 | BBC Radio 4 |
| 97.8 MHz | 20 | BBC Radio 1 |
| Frequency | Block | Operator |
|---|---|---|
| 218.640 MHz | 11B | Bauer Inverness |
| 225.648 MHz | 12B | BBC National DAB |
Below is a list of DTT transmitters that relay television broadcasts from Knock More.(Note: only public service broadcast multiplexes are broadcast from these relay sites)[15]
| Transmitter | kW | BBC-A | BBC-B | D3&4 | Pol. |
|---|---|---|---|---|---|
| Aviemore | 0.0026 | 28 | 25 | 22 | V |
| Avoch | 0.002 | 32 | 34 | 35 | V |
| Balblair Wood | 0.00263 | 32 | 34 | 35 | V |
| Craigellachie | 0.014 | 40 | 43 | 46 | V |
| Grantown | 0.07 | 44 | 41+ | 47 | V |
| Kingussie | 0.02 | 46 | 43 | 40 | V |
| Lairg | 0.0026 | 44 | 41+ | 47 | V |