Crwbin Instation

The wireless sets were concealed in a dugout, described as a cave blasted out of the rock. Royal Signals soldiers Jack Millie and Bert Davis recalled that a dummy fire watch tower was built on Mynydd Llangyyndeyrn to be able to disguise the aerials in handrails, on an otherwise treeless moor. The wood was from a dump of telegraph poles that were "acquired" and towed across the moorland by a Bren Gun carrier. David Wemyss remembered that the way into the OB was by moving the Elsan to one side and lifting the floor, suggesting that there was an above ground structure at the site. The four legs of the tower were each built from two telegraph poles bolted together using the existing holes. The aerial was then installed in the cross rails of the platform. Bert Davis recalled having to carry the batteries and other equipment across the moor.