The Bressay transmitting station in Shetland was opened by the BBC on 15th April 1964 to bring VHF monochrome television to the islands.  There are two towers on the site, one essentially for TV and one essentially for radio.  VHF television has now ceased but in 2004 Bressay transmits UHF analogue colour television from BBC1, BBC2, ITV and Channel Four (but not Channel Five) and UHF Digital Terrestrial Television (DTT). 

The second tower is used for VHF/FM radio broadcasting and this transmits the high power BBC national and local opt-out services together with the Independent Local Radio station SIBC (Shetland Isles Broadcasting Company).  The programmes for SIBC were originally fed to the Bressay site from the studio in Lerwick via a low power radio link on 102.2 MHz (20 watts - vertical), which also acts as a small filler for the town.  Since 1994, however, the feed from the studio to the transmitter has been via U.H.F. (Ultra High Frequency) radio link.  The 102.2 MHz v.h.f. transmitter is now essentially a standby service that listeners can retune to should Bressay fail, which has happened. 

These details have been provided by Ian Anderson of SIBC kindly e-mailed us to confirm the technical details of the station and also points out that SIBC uses the two vertically polarised Marconi R1000 aerials seen in several of the photographs below.  Thanks Ian!

The transmitting aerials used by the BBC radio services are the six tiers of large "Coniex" crossed dipole aerial panels at the top of the 'radio mast'. 

In SIBC's Ian Anderson's e-mail he also notes that: "Your e.r.p. for SIBC is undercalculated, although it is difficult for us to give precise figures.   If the BBC is "high power" we cannot be "low power" since were are on parity with the weakest of the BBC services (the variance in the Q of the aerial system means that the services erps are not all the same) in some lobes, and no more than 4-5dB down in general.  It has been like that for 10 years, with 1 dB increased reflection from the Orange metal work (just above) added a few years ago.   It just shows that a well placed dipole pair with reflectors can be relatively efficient, even against eighteen Coniex crossed dipole panels".  Very many thanks to Ian Anderson of SIBC for the very useful contribution and clarification.  More below....

* The 4kW figure that I originally used are those published by The Radio Authority and later Ofcom. I did, however, read in "Communication" (the monthly publication of the BDXC - British DX Club) in around 1994/5 that SIBC had been given authorisation to increase transmission power from 4kW vertical to 50kW mixed (i.e. 25kW (V) + 25kW (H)), making it most powerful ILR station in the UK.  Although the current technical parameters published by Ofcom show the permitted maximum e.r.p to be 50kW mixed, SIBC continues to use the two Marconi vertical antennas and the power is now as Ian Anderson most kindly clarifies.

From what Ian has written that the output from SIBC is probably nearer to 8kW vertical on average (i.e. about 4dB down from the BBC's 43kW mixed i.e. 43kW ÷ 2 = 21.5kW less 4dB = 8.6 kW).

This may change in the future as in 2012 SIBC hope to install a new transmitter and have it combined into the main Coniex antenna system used by the BBC's national stations. 



The first photographs show the tower that carries the radio transmitting aerials:

This photograph details two sets of aerials:
1/ Two horizontal log periodics (top right) that appear to be VHF receive (RBR) aerials for BBC Radio
2/ Below the pair of Orange mobile phone aerial panels are two vertical Marconi R1000 dipoles, (bottom left with white dipole centres)
with rear reflector, that are used by the ILR station SIBC that produce near 8 kW.

A view from the hill with the radio tower on the left and the television tower on the right