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Tropospheric - Installations

Page history last edited by David Samways 5 years, 2 months ago





North Sea Oil Rigs communication


Input provided by Roger Godfrey - 14th February 2014


Brimmond Hill is a 265m hill SW of Dyce airport just west of Aberdeen.  BP owned a private telecomms system between Brimmond Hill shore terminal and their Forties Field platform.  This was the first of the North Sea comms systems installed by Marconi and Terry Canham was the project manager.


Phillips Petroleum based in Bartlesville Oklahoma, procured the second private system between Eston Nab in Tees-side and their Ekofisk platform, with additional links to intermediate off-shore pumping stations.  This was the first project I was involved in and the project manager was Doug Weston (deceased). 


Mormond Hill is a 230m hill in the district of Buchan near Fraserburgh in Aberdeenshire.

Mormond Hill was run by the Post Office as the shore terminal of a link to the Frigg field Intermediate platform.  This platform belonging to Total oil Marine was a repeater for comms and telemetry traffic to and from the Frigg production platform.

As far as I know there were no more private systems and all the contracts after Ekofisk were between PO owned shore stations and oil/gas operator owned offshore terminals.


Mormond Hill also carried a link to the Occidental Piper Alpha platform which was destroyed by fire on 6 July 1988.


The other PO tropo terminal stations were at Mossy Hill, Scousburgh just north of Sumburgh airport on Shetland main island.

These terminals were linked to the off shore production platforms:  Thistle and Cormorant (Shell), Ninian (Burmah Oil), Alwyn (Total), Frigg (Total) and Beryl Apha (Mobil).


I project managed the PO shore stations working with Ralph Goodchild (Installations) and David Oliver (Antenna Systems).

These contracts were completed in 1975 against incentive payment conditions.


During the period 1973-78 I also managed the equipment supply to the tropo terminals at Beryl Alpha, Frigg and Piper Alpha.  In addition to tropo we supplied LOS links, multiplexers, PABXs, public address systems, sound powered telephones, aircraft beacons and ground to air radios.  Some of the Marconi engineers involved were Mike Deacon, Frank D'Dousa, Hugh Kendall, Dick Clubley, John Coleman, John Osborne, Ron Geary, Wilf Easterbrook among others.  Mobil had a telecoms manager Jim Dorman who was ex-Marconi and who I believe still lives in Great Baddow.


A copy of the system network diagram is available here.



OMAN Integrated Air Defence system


Input provided by Andy Reed - 4th March 2015


Marconi Communications provided communications in support of the Marconi Radar contract, linking radar sites to SOAF airbases and HQ.


The main Tropo links were all analogue Seeb (Sib) to Fahud.  Then Fahud to Masirah and Fahud to Thumrait.  Thumrait then linked to Salalah airbase by LOS with two repeater stations.


Most of the LOS links used Granger Tx/Rx.  I think the multiplexors were GEC but there was some much older Electoman kit for local short haul routes to individual army bases.


We also looked after the telephone system on the bases with a Mitel switch.


While I was there Martin Bates came out and I recall sqeezed an extra 24 channels into the tropo. 


I think it was 87 when an additional tropo link went in from Sib to Khasab


An overview of the network diagram is shown below.






Comments (2)

Norman Whitehead said

at 3:42 am on Mar 21, 2014

Was Ekofisk - Emden installed as a private system? These links used automatic transmit power control to prevent the possibility of 'overshoot' interference to systems in Europe in periods of exceptional propagation conditions. This use of power control is the only one I am aware of, but there may be others.

Planning permission for the Phillips terminal at Eston Nab was opposed by local environmental groups in Teesside because it was on the edge of the North Yorkshire Moors National Park, and because it was on the skyline when viewed from Eston below. I took part in a 'Town Hall' meeting to explain the proposals for the residents of Eston, and appeared as 'Expert Witness' for Phillips at the Public Enquiry in Middlesborough (Sept / Oct 1974). The outcome was that Phillips was granted planning permission for a limited time (I think it was 10 years) after which they would either have to re-apply to extend permission or replace the tropo link with an alternative system. I don't know what happened after that, but looking at Eston Nab now on Google Earth I see a much larger site with a satellite dish and lots of cellphone antennas, but no tropo dishes. The current site is far more unsightly and obtrusive than the tropo station ever was!

It is perhaps worth mentioning that the BP Forties system was unique in having a single antenna system (pair of antennas) onshore working to two separate platforms, Forties Alpha and Forties Charlie. Both platforms were within the beamwidth of the onshore antennas, so no switching between separate onshore antennas was required for alternate routeing.

TimGJ said

at 3:29 am on Mar 6, 2015

In Oman
The Muxes were GEC, Telectron, Lenkurt DTL and Granger 7300 DTL. The Seeb to Khasab Tropo was digital the LOS and muxes were Marconi italiana secure Military units

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