British Kinematography (1951)

Lfcfi BRITISH KINEMATOGRAPHY Vol. 18, No. 4 erected on the studio water tower to afford the dipole a height above ground of about 98 ft. The master station was then installed in the studio manager's office, and trials over the territory between Ealing and Tower Bridge showed clearly that the aerial mast employed was not sufficiently high to " see " the car at London Bridge over the intervening metropolis. Setting off from the studio, reliable communication was maintained only Fig. 6. Temporary Ultra Short Wave Aerial at Ealing Studios, used for Radio Telephone Communication with Location Units. (Note : The Scaffolding Structure was already around the Chimney for repair work, and was extended to give additional height to the aerial, which is at the extreme top). as far as Westminster, and at Waterloo Bridge signals were only just readable. It will be interesting here to relate that during one test, the studio car was stationary on the west side of Waterloo Bridge itself, and it was noticed that whenever a bus passed by on the far side, signals at the car receiver came up to full strength. The steel sides of the buses were naturally presenting a large reflecting surface to the wave front, and when the car and bus were abreast the signal at the receiving aerial was, of course, considerably augmented. Tests were continued a few days later with the studio aerial mast 25 ft. higher. The route between the studio and Tower Bridge was covered again and on this occasion a good signal was maintained all the way, with the exception of certain local " blind spots." This improvement resulting from such a limited increase of aerial height aroused the enthusiasm of the studio construction team, who decided immediately that their mast was not quite as high as it could be. A few days later the dipole aerial had been raised a further 22 ft. (145 ft. above ground) and the fixed station had been moved to a new position near the foot of the mast. A remote control unit was installed in the studio manager's office and linked to the main equipment with suitable cable. Subsequent reports established that the Tower Bridge area was now safely within operational range. Aerial Improvements The studio team responsible for the efficient operation of the scheme then took steps to guard against any possibility of " blind " spots interfering with the success of their project. Remembering the tests on Waterloo Bridge and the effects experienced when buses were passing, attention was directed to the improvement of the receiving aerial system. A sleeve dipole similar to that used for the fixed station was bolted to a small telescopic pole and this latter was bolted in turn to the rear of the vehicle bodywork. With the pole in the collapsed position the dipole was just clear of the vehicle roof and remained thus for travelling purposes. When stationary7 in what would normally be a blind " spot, however, the pole could be extended up to 25 ft. and in general communication would be re-established. Surveys in many quarters showed clearly that for this particular application the telescopic aerial had decided advantages, and ranges up to 40 miles were recorded. Throughout the location work on the film referred to, the radio telephone was used extensively, and according to reports by the production staff, the