Abstract :
The paper surveys the contribution which very high frequency radio can make to sound broadcasting in Britain. It points out that the total cost of establishing a V.H.F. service may be several hundred millions of pounds and that a major return in terms of public service is essential for such an outlay. The view is taken that if V.H.F. is to be used merely to duplicate the existing transmissions on the grounds that improved reception will be obtained, then the cost cannot be justified. Such a proposal would fail as it has failed in other countries. The ability of V.H.F. to give improved reception will in any case be limited by economics. The outstanding advantage of V.H.F. in broadcasting is its ability to make available large numbers of new programmes and services which have until now been barred by the technical limitations of the medium-wave band. In particular it is pointed out that V.H.F. is by its nature particularly suited to the establishment of local broadcasting on a wide scale. The important advantages of this approach to V.H.F. broadcasting both in peace and in war are reviewed. The case for the adoption of amplitude modulation is first, that in the limited frequency band available in this country, A.M. will permit a wide development of new services to take place, whereas if frequency modulation (F.M.) were to be used there would not be adequate frequency space for any considerable expansion. The second decisive factor which favours A.M. is cost. It is pointed out that by far the greatest part of the total cost involved will be in the new receivers and convertors required by the public. A number of possible A.M. and F.M. receiver designs are reviewed in terms of cost and performance and it is concluded that here again the advantage is with A.M. Other aspects of the problem are discussed, each of which points to the same conclusion.
