. The Bell System technical journal . g. 10 is a photograph of this apparatus. Other tests also going on at Holmdel, N. J., were concerned withthe measurement of the comparative delay times and the respectiveangles of the various paths of the waves.■^ To permit this, the BritishPost Office transmitter sent pulses of very short duration. At the re-ceiving point, a single transmitted pulse frequently appeared as severalspaced pulses when a sweep circuit was employed. The spacing en-abled the measurement of the relative time delays. It was found to DIRECTIVITY STEERING FOR FADING REDUCTION 203 be
. The Bell System technical journal . g. 10 is a photograph of this apparatus. Other tests also going on at Holmdel, N. J., were concerned withthe measurement of the comparative delay times and the respectiveangles of the various paths of the waves.■^ To permit this, the BritishPost Office transmitter sent pulses of very short duration. At the re-ceiving point, a single transmitted pulse frequently appeared as severalspaced pulses when a sweep circuit was employed. The spacing en-abled the measurement of the relative time delays. It was found to DIRECTIVITY STEERING FOR FADING REDUCTION 203 be the apparently invariable fact that the earlier arriving pulses are thelower in angle with the horizontal and are relatively stable in tests suggested that a somewhat similar scheme of observationswould be useful to the present work since, if pulses were similarlyemployed, one would actually see the effect on each individual path ofsteering the antenna. Accordingly, cathode ray equipment was constructed employing a. Fig. 8—Cathode ray oscillograph pulse figures when using the circular sweep circumference is traversed by the spot in twenty milliseconds. circular sweep system, in place of the usual linear sweep, thus makingthe entire time interval always in view. Figure 8 illustrates how thepulses sometimes appeared during this sweep. Since the pulses werealways vertical, their definition was lost if permitted to slide down into
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