A 2¾ x 2¼ film negative. On board the Type 12 frigate Yarmouth (1959) alongside the South-West Wall in Portsmouth Dockyard. Inside the Electronic Warfare Office on the centreline on 1 deck between 35½ and 38 stations looking forward and to port from near the door. There are three operator's positions, each equipped with a morse key. The operator on the left has an amplifier and display unit with a small display screen, the operator in the centre has a double-banked unit with tuning dials and the right-hand operator has two tall units numbered B40 and B41 and labelled Receiver LAY No. 1 and Receiver CAZ No. 2. An E.W. stateboard is on the port bulkhead. The clock reads 10.28.