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The report deals with that portion of the Commission's UHF Project that was concerned with the installation of observation receivers at 768 randomly selected locations within 25 miles of the Empire State Building. All of the television signals observed originated at this site.

The side-fire helical antenna, successfully used for UHF and VHF high channel television transmission, has now been adapted for low channel VHF service. Investigation of properties of a helical radiator wound around a polygonal supporting structure has made possible the required increased bandwidth and provided directional patterns for special TV coverage applications. Through scale model work, a channel 2 directional antenna has been developed for installation around a triangular tower section.

TASO made a thorough study of the characteristics, performance and cost of television transmitters, antennas and transmission lines, and translators. The results of these studies gives a clear picture of the technical and economic factors involved in operating television transmitters in the VHF and UHF bands. This paper summarizes some of these studies which are reported in detail in the TASO Report, "Engineering Aspects of Television Allocations."

Incorporate with the over-all study conducted by TASO, Panel 3 (Field Tests) in its study of reception problems conceived a six-page questionnaire which was circulated to that segment of the industry most closely associated with these problem areas?the television servicemen in communities across the nation. The questionnaire dealt with reception conditions, antennas, transmission lines, receivers and allied questions on both VHF and UHF covering both color and monochrome. The statistical compilation of answers received from the cooperating TV servicemen is included in this paper.

The alternatives are described for achieving one megawatt Effective Radiated Power in the UHF-TV band. The new 0-E 45 KW and 23 KW transmitters are described. The different high power antenna approaches are discussed. Steps towards converting existing 1 KW and 0-E 12 KW stations are explained in detail.

Television Allocation Study Organization's (TASO) Panels 1 and 2 are concerned with the television transmitting and television receiving equipment arts respectively. The general problems and specific studies undertaken for a critical evaluation of VHF and UHF to obtain data for the FCC are set forth.

UHFテレビの実施に伴い, サーキュレーターおよびアイソレーターといった回路素子のテレビ放送機器への利用が, かなり重要な研究テーマとなってきた.この論文は, これら回路素子をアンテナ共用回路, 残留側波帯〓波器などに使用し, 良好な特性を得ることができたものをまとめたものである.

The purpose of this paper is to present data which correlate a given level of picture quality with some corresponding level of measured field strength. The data were gathered by actual house-to-house surveys in conjunction with field strength measurements. This procedure was followed rather than making laboratory tests on new receivers because it was desired to evaluate coverage as it actually was, not as it ought to be. Particular attention was paid to differences between UHF and VHF channels with respect to receiver and antenna performance in given field strengths. The ranges of field strengths required for a passable picture quality are fairly well established for each band of television channels.

To meet FCC radiation limits, uhf strips and tuners must be designed to take full advantage of normal double-tuned circuit skirt attenuation so that a prohibitive increase in cost and complication can be avoided. UHF strips must also meet the normal radiation limits on the oscillator fundamental, as well as the limits on used and unused harmonics, on both the vhf and uhf antenna connections. Techniques and typical designs are described, and typical field measurements are given.

Some of the factors involved in the application of an ultra-high-frequency radio link to wire telephone plant are discussed. A description is given of an ultra-high-frequency radio circuit which has been set up and operated between Green Harbor and Provincetown, Mass. This circuit is used as a part of a regular toll telephone circuit between Boston and Provincetown. It has been found that the equipment can remain in operation over considerable periods without attention or adjustment.

This report presents a technique which enables the antenna design engineer to establish his own design and location criteria and the associated trade-offs and to analyze existing circuits. Conclusions are drawn about shipboard antenna design and location for the ship-to-ship case (example: Ship antenna height has little effect on circuit performance at low vhf frequencies); the ship-to-air case (High ship antennas and the highest frequencies produce detection contours with large amounts of lobing and the shortest distances of satisfactory performance); and the general case (High time availabilities require large protection biases to achieve the desired performances). An appendix indicates the effect of a complex shipboard environment upon a sample receiving system.

The author ruminates and wonders how many clues to marvelous electronic discoveries lie latent in the literature of our field and in the engineer's notebook - unique or unexpected eddies in a main current of research effort that were dutifully recorded at the time, but, through the urgency of other programs, have received no further attention.

A TEM transmission line having a circular or rectangular center conductor placed between two parallel plates or inside a rectangular tube, has been used in the construction of a number of uhf antennas and ? wave filters. The characteristic impedance of the class of transmission lines, of which the above-mentioned are particular examples, can be theoretically calculated by a number of methods. A review of the theoretical methods using the above transmission lines as examples will be given. Comparison between theoretical and measured results will be given to show the usefulness of the different theoretical methods.