Fenix Signalling completes its work on the RETB project

Fenix Signalling completes its work on the RETB project in the Scottish Highlands & Far North

Fenix Signalling has completed its part in the RETB upgrade in the Scottish Highlands, having recently finished the second phase.


The upgrade was necessary due to OFCOM’s decision to reallocate the operating frequency in this region for digital TV throughout Europe. The project, commissioned by Network Rail and led by telent Telecommunications Ltd, required changes to be made to the frequency of the base stations. However, the wider implications included the development, modification and renewal of depot, engineering and trackside equipment to provide a fully operational communications system.

Phase 1

Working in collaboration with telent, the Fenix team – led by Testing Manager, Geoff Clark – completed Phase 1 of the project in the early part of 2016. This phase required successful delivery of the Train Protection Warning System (TPWS) signalling testing works on the Scottish West Highland Line. This was the first part of the Radio Electronic Token Block (RETB) Next Generation scheme schedule on the West Highland and Far North Lines.

Fenix Signalling was responsible for all the signalling and testing works in the project. The company initially completed trials at two sites; subsequently, work was completed at a total of 19 sites on the West Highlands Line, along 165 miles of track. Modifications to the TPWS power supplies to enable the change of frequency were also required.

There were various challenges overcome along the way; many of the locations were extremely inaccessible, needing a journey of around five hours in a 4×4 between each site; severe winter weather conditions and storms increased the logistics challenge.

The success of the first phase was largely due to the close collaboration on site between the signalling and telecommunications disciplines; the Fenix and telent worked very effectively to meet the deadline dates.

Phase 2

The collaborative working association between Fenix Signalling and telent continued, and both teams worked closely in these remote Scottish Highland locations.

The second phase of work required the commissioning of the TPWS on the Far North Line. This includes track running from Invergordon out to the Kyle of Lochlash in the west, and up to Thurso and Wick in the north, covering in excess of 200 miles and the most northerly rail track in the UK. Fenix Signalling was responsible for the principles testing process and site commissioning of the new Solid State Interlocking (SSI) at Inverness, and the split of the Far North interlocking.

Much of the frequency conversion work was completed at night, and local wild life required innovative “hazard” prevention as the wild deer wandered onto the roads between sites, “deer-watch” aside; Fenix successfully completed the new interlocking, checking all signalling was working effectively and efficiently. Under Geoff’s leadership as signalling tester in charge, he ensured that the project was delivered on schedule.

The project was handed over in October 2016

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