One day Charles Garland and I were invited down to the refitting dock at Bristol to lunch with Captain and Officers of H.M.S. WREN undergoing a refit. It was the first time during the war that I had been on a Naval Vessel; we found it propped up in a dry dock, accessible only by a 12" wide plank. I got across it safely enough, but after a pleasant two hours, spent mostly in the ward room, my shoreward navigation was decidedly inaccurate, and the dock looked horribly deep!
I had never before realised the cramped conditions of life on a destroyer or frigate; it was really unbelievable. The cramped living space for the crew, the Radar office about the size of a packing case, and all the guns, boilers, turbines and magazines enclosed in a shell, perhaps 1/4" thick! no wonder a broadside lifted the valves out of our earlier sets.
I suppose the job on which we excelled ourselves was the famous AI Mk VIII, a 10 cm interceptor set for use in night fighters such as the Beaufighter and the Mosquito. It was being developed at the TRE by a team under Professor P.I. Dee, now I believe at Glasgow University to use the Magnetron Valve which had been passed for mass production to a team at the British Thomson Houston Co., Rugby from Birmingham University.
We got in on the job at a very early stage, as Tony Martin at WDU had been called into consultation on the design at Malvern, and we at the factory, having to shorten as much as possible the inevitable time layon between the original lash-up model and the final production version, got TRE to agree with permission from Air Commodore Leedham to attend the design conferences at both Malvern and Malmesbury from the start.
The frequencies used in these 10 cm sets, and the operating altitude of 35,00 feet youed entirely new problems in electrical and electronic engineering. The pulse transformer operated at some 5,000 volts, and the job of containing such a voltage at this wavelength in rarefied atmosphere of that altitude and in a few cubic inches of space seemed almost impossible.
Martin's test devised in conjunction with the Moulton Rubber people at Bradford-on-Avon, a miniature synthetic rubber tank in which the transformer was entirely immersed in a special high voltage transformer oil. I do not think the AI Mk VIII would ever have passed its tests without this revolutionary idea. The designer-scientist who co-ordinated the liaison between the TRE and Malmesbury was Dr. Burcham, a brilliant physicist now Professor of electronic engineering at Birmingham; also working with us were a scientist who was really a physiologist, Dr. Alan Hodgin, now President of the Royal Society and Dr. Touche, a close collaborator with Watson Watt in centimetric and other Radar Development.
They had all been closely concerned at TRE with the use of the magnetron in solving the problems of Airborne Radar and later they produced further developments for pin-point detection, as well as a tail gunners set to warn our bomber pilots of the approach of enemy night fighters from the rear, called I seam to remember, "Monica". There was also a device for identification of "friend or foe" called I.F.F.
