Stirling Transmitting Station
Stirling Transmitting Station is a transmission facility on Earl's Hill southwest of Stirling, Scotland. It was built at the end of the 1950s for the radio navigation system Dectra with a 183 metres (600 ft) tall guyed mast radiator, which was used after shut-down of Dectra as a Decca transmitter.[1]
Dectra and Decca
[edit]Decca and Dectra were hyperbolic radio navigation systems. Decca has first developed by UK company Decca Radar during World War 2. It uses low frequency signals from beacons to allow the receiver to determine their position. Conventional navigation involves measuring the distance from two known locations, radio navigation works in a similar way but using radio direction finding.[2]
Dectra was a modification of the Decca System designed for aviation. Dectra worked with larger antennas and with higher power to cover the Atlantic Ocean.[3] It could only provide tracks rather than locations at long distances and VOR/DME was preferred by the ICAO.[4] The Decca system closed down on 31 March 2000.[5]
Stirling was on two Decca chains - North British (3B) and Northumberland (2A). It was a slave station in both chains. In the North British chain it was the purple station, broadcasting on a frequency of 70.538 kHz. In the Northumberland chain it was the red station, broadcasting on 112.607 kHz.[6]
Stirling site
[edit]The Decca mast was demolished in the early 2000s.[7]
There are a number of masts on Earl's Hill including three that were used for Differential GPS, a system for nautical navigation which was discontinued in 2022.[8][9]
References
[edit]- ^ "Decca - North British". www.jproc.ca. Retrieved 11 April 2025.
- ^ Appleyard, S.F.; Linford, R.S.; Yarwood, P.J. (1988). Marine Electronic Navigation (2nd ed.). Routledge & Kegan Paul. pp. 77–83. ISBN 0-7102-1271-2.
- ^ Powell, Claud (March 1958). "The Decca Navigator System for Ship and Aircraft Use" (PDF). The Institution of Electrical Engineers. Retrieved 11 April 2025.
- ^ Blanchard, Walter (September 1991). "Hyperbolic Airborne Radio Navigation Aids — A Navigator's View of their History and Development". The Journal of Navigation. 44 (3). doi:10.1017/S0373463300010092. S2CID 130079994.
- ^ "Decca Navigator - History". www.jproc.ca. Retrieved 11 April 2025.
- ^ "Decca Navigator - Chains". www.jproc.ca. Retrieved 11 April 2025.
- ^ "Earls Hill - Guyed mast replacement possibly early 2003". mb21. Retrieved 11 April 2025.
- ^ "Digital Global Positioning System (DGPS) Infrastructure Removal at Earls Hill [Notice]". bidstats.uk. Retrieved 11 April 2025.
- ^ "Tri-GLA decision to discontinue DGPS service in March 2022". Trinity House. 28 August 2020. Retrieved 11 April 2025.