HC Deb 02 November 1955 vol 545 cc116-8W
57. Mr. Hector Hughes

asked the Minister of Transport and Civil Aviation to make a statement on the new inexpensive and compact radar apparatus for guiding small fishing vessels into harbour when visibility is bad, which has been developed by the Admiralty Signal and Radar Establishment at Portsdown.

Mr. Boyd-Carpenter

This radio device has been developed by my Ministry's scientific group at the Admiralty Signal and Radar Establishment. Its purpose is to show that a cheap and simple radio equipment can be used to define a safe line of entry into a harbour in poor visibility.

Following is a description of the device:

MICROWAVE HARBOUR BEACON

The system is an adaptation of the old Lorenz type of landing aid for aircraft and consists of a 3 cm. radar type transmitter mounted at a harbour entrance and radiating from two aerials which have overlapping beams. The transmitter is so sited that the line of intersection of the two beams is along a safe course line for entering harbour.

The output of the transmitter is switched in turn to each of the aerials in such a sequence that the morse letter B(- …) is transmitted from one aerial and the morse letter V(- -) from the other aerial. The characters of one letter are transmitted during the period of the space intervals between the characters of the other letter with the result that along the line of intersection of the two beams, where the amplitude of the signals from each aerial is equal, a continuous signal is received.

The ship's receiver is a pre-tuned crystal receiver coupled to a small horn aerial. The receiver and its power supplies are built around the horn, measure 4in. x 5in. x 5in. and weigh 4½ lb. The power supplies are provided by a 4½ volt flashlamp battery. An improved model of the receiver is supported on a rotatable searchlight mounting. This is intended for fitting through the wheelhouse roof of a small boat. The output of this receiver is brought out to a 'phone jack on the rotating arm into which a loudspeaker attachment may be plugged.

The trials and demonstrations of the apparatus have been carried out at Fraserburgh and Arbroath and the equipment operated very satisfactorily out to a range of approximaely seven miles from the harbour.

The device has thus been demonstrated to the fishing interests and radio manufacturers. Its future development and use is their responsibility. If they wish to pursue this project any further advice or technical assistance which my Department can give is at their disposal.

s.s. "Tresilian" (Lifebelts)

63. Mr. Awbery

asked the Minister of Transport and Civil Aviation if his attention has been drawn to the experience of one of the survivors of the s.s. "Tresilian" in that the lifebelt he was wearing had a tendency to climb up the body and that he had to keep pushing it back to its place; and if he will examine the suitability of this type of life-belt in view of this defect.

Mr. Boyd-Carpenter

No doubt the hon. Member is referring to evidence given on this subject before the Court of Formal Investigation which is at present inquiring into the loss of the s.s. "Tresilian." My Department is watching this matter most carefully, but the hon. Member will not expect me to anticipate the findings of the court.

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