UNITED  STATES  DEPARTMENT  OF  COMMERCE  


RECOMMENDATIONS
   FOR  REGULATION  OF  RADIO   

ADOPTED  BY  THE

THIRD  NATIONAL  RADIO  CONFERENCE

CALLED  BY

HERBERT  HOOVER
SECRETARY  OF  COMMERCE
________
 
OCTOBER  6-10,  1924


[SEAL.]
DEPARTMENT  OF  COMMERCE.
UNITED  STATES  OF AMERICA.




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1924

 
This is an HTML version of the original government document, Recommendations for Regulation of Radio Adopted by the Third National Radio Conference, October 6-10, 1924, issued by the Government Printing Office in Washington, D.C. for the Department of Commerce [C1.2:R11/924].

This HTML version is based on a photocopy of the original 35-page publication. It incorporates the original contents (except for some minor elements, such as page number references), keeping as much as possible the layout of the original document.

RECOMMENDATIONS  ADOPTED  BY  THE  THIRD  NATIONAL  RADIO  CONFERENCE


C O N T E N T S


1. Opening address by the Secretary of Commerce
2. Organization of the conference
3. Final recommendations
4. Reports of subcommittees:
      Subcommittee No. 1: General allocation of frequency or wave-length bands
      Subcommittee No. 2: Allocation of frequency or wave-length bands to broadcasting stations
      Subcommittee No. 3: General problems of radio broadcasting
      Subcommittee No. 4: Problems of marine communication
      Subcommittee No. 5: Amateur problems
      Subcommittee No. 6: Interference problems
      Subcommittee No. 7: Interconnection
5. Summary of frequency or wave-length allocations
 

I.  OPENING  ADDRESS  BY  HERBERT  HOOVER,  SECRETARY  OF  COMMERCE

    This is the opening of the Third Annual National Radio Conference at the Department of Commerce. It is a great pleasure to me to welcome you to this session. You who represent the radio fans, broadcasting stations, engineers, and manufacturers have come at my request to again consider the situation in radio from a national point of view and to determine what steps can be taken to advance the art and improve its service.
    Through the cooperation of the broadcasting stations throughout the country, at this opening session we are inviting the listeners of the country to sit in because they are obviously interested in all questions of radio development, and we all wish them to participate in the consideration of our problems.
    I have called the conferences of each of the last three years in the confidence that it was only by your cooperation that the requirements of this great service could best be met. There are certain minimum regulatory powers in the Department of Commerce. They are inadequate to meet the shifting situation that this developing art constantly presents. Nor could any legislation keep pace with the changes imposed by scientific discovery and invention now going on in radio. I have been convinced, however, that we could meet these problems by organized cooperation of the industry itself. I need tell no radio listener that this industry is unique in that unless it has stringent rules of conduct to which all elements adhere it will die of its own confusion. We must have traffic rules, or the whole ether will be blocked with chaos, and we must have safeguards that will keep the ether free for full development.
    With the development of the art this problem has become one of the most complex technical character ever presented to the Government for solution. At every succeeding conference we have had more and more difficult problems to solve, and those which we present today are of a complexity greater than ever before.
    It is in a large sense the purpose of this conference to enable listeners, broadcasters, manufacturers, marine, and other services to agree among themselves as to the manner in which radio traffic rules may be determined. Like the two previous occasions, this may be called an experiment in industrial self-government. Through the policies we have established the Government, and therefore the people, have to-day the control of the channels through the ether just as we have control of our channels of navigation; but outside of this fundamental reservation radio activities are largely free. We will maintain them free--free of monopoly, free in program, and free in speech--but we must also maintain them free of malice and unwholesomeness.
    Radio has passed from the field of an adventure to that of a public utility. Nor among the utilities is there one whose activities may yet come more closely to the life of each and every one of our citizens, nor which holds out greater possibilities of future influence, nor which is of more potential public concern. Here is an agency that has reached deep into the family life. We can protect the home by preventing the entry of printed matter destructive to its ideals, but we must double-guard the radio.
    Radio must now be considered as a great agency of public service, and it is from that viewpoint that I hope the difficult problems coming up before this conference will be discussed and solved.
    At the first radio conference I hazarded some modest anticipations as to its development and use. Some thought them visionary, yet we passed every point of these anticipations within 18 months. We have, in fact, established an entirely new communication system, national in scope. In the whole history of scientific discovery there has never been a translation into popular use so rapid as in radiotelephony. So late as the year before I became Secretary of Commerce there were no broadcasting stations. At the end of four years 530 are in operation, making radio available to every home in the country. The sales of radio apparatus have increased from a million dollars a year to a million dollars a day. It is estimated that over 200,000 men are now employed in the industry, and the radio audience probably exceeds 20,000,000 people.
    We may well be proud of this wonderful development, but in our self-congratulation let us not forget that the value of this great system does not lie primarily in its extent or even in its efficiency. Its worth depends on the use that is made of it. It is not the ability to transmit but the character of what is transmitted that really counts. Our telephone and telegraph systems are valuable only in so far as the messages sent from them contribute to the business and social intercourse of our people. For the first time in history we have available to us the ability to communicate simultaneously with millions of our fellow men, to furnish entertainment, instruction, widening vision of national problems, and national events. An obligation rests upon us to see that it is devoted to real service and to develop the material that is transmitted into that which is really worth while. For it is only by this that the mission of this latest blessing of science to humanity may be rightfully fulfilled.

BROADCASTING  PROGRAMS

    The first matter of importance which I desire to lay before you is our broadcasting programs.
    When broadcasting first started, the phonograph was a sufficient attraction to the radiotelephone listeners, who were swayed chiefly by curiosity and marvel at the new discovery. Public interest has long since passed this stage. Broadcasting would die in 24 hours if it were limited to transmission of phonograph records. We have made great improvements in material transmitted. Original music, speeches, instruction, religion, political exhortation, all travel regularly by radio to-day. Program directing has become one of the skilled professions. I have, indeed, a great feeling for the troubles of the director in his efforts to find talent and to give to his audience the best that lies at his command. He has done extraordinarily well.
    But we require a still further advance in the character of material beyond the capacity of local station directors if the art is to emerge entirely from the curio and entertainment stage to that of fundamental service. Experimental broadcasting upon a national scale by interconnecting stations by wire during the past year has now brought us to the stage where we know it can be done. It has opened a new vision to us. The local material available for the local program is of the highest importance but is not, in my view, enough to maintain the assured interest necessary for the support of the industry nor to fulfill adequately the broadcasting mission.
    So far as the art has developed, I think we all agree that for accuracy and regularity of reception we can depend only upon the local broadcasting stations. I know the importance of these smaller stations to the communities they serve. I know that there are millions of crystal sets and small tube sets whose owners are practically compelled to-day to rely upon the stations at their doors and are getting good service from them. These are the people I have in mind and the ones I primarily want to serve, for the owner of the multitube set, reaching out for an indefinite number of miles, is pretty well able to look out for himself. I want to see the little fellow get something more than he has now. My proposition is that the local stations must be able to deliver every important national event with regularity. The local station must be able to bring to its listeners the greatest music and entertainment of the Nation, but far beyond this it must be able to deliver important pronouncements of public men; it must bring instantly to our people a hundred and one matters of national interest. To this it must add its matters of local interest. This can only be accomplished by regularly organized interconnection on a national basis with nationally organized and directed programs for some part of the day in supplement to local material.
    It may be stated with assurance that the greatest advance in radio since our last conference is the complete demonstration of the feasibility of interconnection. We owe a debt of gratitude to those who have blazed the way. The pioneers have been the American Telephone & Telegraph Co. in wire interconnection and the Westinghouse Electric & Manufacturing Co. in radio interconnection through the use of short wave lengths. Their experiments have involved technical skill of the highest character which could be found or contributed by few other organizations in the world. Their expenditures, running into the hundreds of thousands of dollars, have been made without direct consequential return. It has been possible to broadcast many national events over three-quarters of the United States during the past year, and the whole country has been covered twice. The service deserves the appreciation of the public for it has demonstrated this great thing to be practicable.
    It is our duty to consider the possibilities and potentialities of interconnection as a regular daily routine of the nation. Unless it be systematically organized we can not expect its continuation. I realize that this matter, except in so far as it may be fostered and encouraged, does not lie in the Government. It would be unfortunate, indeed, if such an important function as the distribution of information should ever fall into the hands of the Government. It would be still more unfortunate if its control should come under the arbitrary power of any person or group of persons. It is inconceivable that such a situation could be allowed to exist; but I am not now dealing with monopoly. Nor is this a question where anyone lays claim to a monopoly. Interconnection is going on to local extent and over the wires of the telegraph companies, the telephone companies, and by radio itself. We have promises of interconnection of wired wireless. If there are several methods, it means that we might have several alternative programs always available. But whatever the method of interconnection may be we are lacking in a definite organization of a national system of programs and a basis of support.
    I believe that the quickest way to kill broadcasting would be to use it for direct advertising. The reader of the newspaper has an option whether he will read an ad or not, but if a speech by the President is to be used as the meat in a sandwich of two patent medicine advertisements there will be no radio left. To what extent it may be employed for what we now call indirect advertising I not know, and only experience with the reactions of the listeners can tell. The listeners will finally decide in any event. Nor do I believe there is any practical method of payment from the listeners.
    This brings me to a definite proposition that I believe is of first importance to every radio listener. I suggest for your consideration the possibility of mutual organization by broadcasters of a service for themselves similar to that which the newspapers have for their use in the press associations, which would furnish programs of national events. It would arrange for their transmission and distribution on some sort of a financial basis just as the press associations gather and distribute news among their members. We would thus have the positive assurance to every household of what is now but an experiment; that is, every home could participate in every national event.

THE  PROBLEM  OF  INTERFERENCE

    One of the most important subjects for your consideration is the rearrangement of our system so as to provide more operating channels for broadcasting stations--more wave lengths. This is the first step to eliminate more of the interference. As you know, our previous conferences have classified our broadcasting stations, have zoned the country in effort to secure these results. The wave lengths of the stations in the same zone were placed at least 50 kilocycles apart, adjoining zones at least 20 kilocycles apart, and distant zones at least 10 kilocycles apart. This was a great step and has been in a large degree successful, but many new difficulties have arisen. Of the present 530 stations 57 are class B, with a power of from 500 to 1,000 watts and having a wide range, and 387 are class A, many using small power and covering small areas. There are still 86 class C stations, most of which have low power, all on a wave length of 360 meters. Our chief trouble is with the class B situation. They are all assigned within the band of 288 to 545 meters, within which there are, under the present system of allocation and excluding the class C band, only 44 available wave bands and only 33 that seem desirable at present. To assign these among the 57 stations necessarily means duplication, although it was the theory of the last conference that individual wave lengths could be assigned to each. As it now develops, only 23 stations either have exclusive wave lengths or are sharing with stations so distant that both may operate simultaneously, while the remaining 34 are compelled to divide time, and the congestion is growing in the large cities, New York and Chicago particularly. A recent survey made by the supervisors of radio of the various districts shows that 21 new class B stations are now under construction and that 25 others are contemplated, so that the question of allocation is one of increasing difficulty. In the light of scientific and technical development in both transmitting apparatus and receiving sets during the year I believe that some changes in zoning or in station separation may now be installed, thus creating additional wave lengths for assignment. It has been suggested, also, that the band now reserved for class B might be somewhat broadened. Removals of class C stations from the class B band and their distribution into individual wave lengths would likewise give some relief, depending on what proportion of the present class C stations qualify for class B licenses. Another constant source of interference are the radio code signals which lie in the broadcasting band. This is the result of the old international agreements before radio broadcasting was discovered. I shall refer to them later.

POWER  OF  BROADCASTING  STATIONS

    Another question of importance is the limit of power to be used in broadcasting. Most class B stations are now operating on 500 watts. A limitation of 1,000 watts is imposed in the license. I understand that there are several stations erected or in course of construction which contemplate the use of power up to 5,000 watts, and I am aware of the suggestions of those who would go beyond even this to so-called "superpower" of 50,000 watts. There is opposition, especially to the latter. Its advocates tell us of the great advantages in the way of louder signals and more distant transmission, while opponents complain of interference and the drowning out of other stations. The latter fear is particularly acute if such a powerful station be located in a congested receiving center. From the viewpoint of nation-wide broadcasting, the question becomes one as to whether we should aim to cover a large territory through a single powerful station or through a number of interconnected smaller ones. We must not stifle progress, but there are vital reasons why we must not do anything that will interfere with the programs of local stations on which so many of our people depend, nor with the wide selective range in programs which they now have. It may be that both purposes may be accomplished without loss to either. I recommend the subject for your most careful consideration and hope that you may be able to reach a satisfactory conclusion.
    I can assure you that this is a question of considerable popular interest. During the past 10 days I have received thousands of letters from men, women, and children all over the country protesting against what they honestly believe would result in depriving them of the chance to listen to the local stations or to use their will in selecting the ones they want to hear. They fear a monopoly of the air. I have written to many of them and intend to write to all. I have said in my letters, and if there are any of them listening to-night I say again, that the air is free to-day, and free it will remain. There is no man nor body of men strong enough to monopolize it even if there was any desire to do so. And always bear in mind that permission to use the air is reserved to the Government. There is, however, much misunderstanding in the loose use of "higher power" or "superpower." There are two very different things involved. The discoveries of the past year show that static can be overcome by somewhat higher power than the 1,000-watt limit at present. It is desirable that all stations should increase in power for this reason. The "superpower" is an entirely different thing. We know very little about it, and it has many implications of interference with local stations and of monopoly which must cause us all a serious thought. On the other hand, a moderate increase in power to the present stations is founded upon the basis of better service by local stations. This is particularly needed by our farmers and others with smaller sets who are now entirely cut off by static in the daytime and summer time.

GENERAL  TENDENCIES  IN  DEVELOPMENT  OF  BROADCASTING

    There seems at present some tendency toward a decrease in the total number of broadcasting stations. September 1, 1923, there were 563 licensed stations. On the same date this year the number had fallen to 533, a loss of 30. This decrease, however, has occurred entirely among the smaller stations in classes A and C. The more important stations, those of class B, have substantially increased, the number then having been 44 as against 56 at present, with 40 others either under construction or proposed. As to whether this shows a real trend toward an abandonment of the smaller stations, with a corresponding additional reliance upon the larger ones, even though more distant, it is too early to determine.
    The broadcasting service of the country, taken as a whole, must be costing $10,000,000 a year, and there is no substantial income. It is therefore of some interest to classify and study the ownership of the stations; to known the probable motives that impel their owners to expend the large sums of money which are necessary for their construction and operation and for which there is usually no direct return. So far as is known to the department, of the present stations 196, or over one-third, are owned and operated by manufacturers of or dealers in radio apparatus, whose interest is, of course, apparent. Department stores and similar mercantile concerns add 39 to this number and publishers 41, making a grand total of 276 known stations, of which 44 are class B, which may be said to have a direct interest in the publicity legitimately resulting from their own broadcasting. On the other side we have 85 educational institutions, 35 churches, 12 city and State agencies, 12 clubs, of which 7 are class B (4 schools, 2 State or city agencies, and 1 church), all of which may be said to operate from more altruistic motives.

MARINE  SERVICE

    Those who are engaged in the use of radio for marine services between ship and shore and ship and ship feel that the present band of wave lengths devoted to their use is too narrow. We must not forget that what is a convenience or a pleasure for us is a necessity for them, and that life may depend on the efficiency of their communication service. There is undoubtedly congestion along our coasts, particularly in the vicinity of such harbors as New York, Boston, and San Francisco. There are two fundamental troubles in the situation, and they are interdependent: First, the character of the apparatus used, and, second, the fact that most ships operate on only two wave lengths, 600 and 706 meters. Practically all marine radio equipment is of the spark type. There can be no economical use of wave lengths until these conditions are improved.
    The London convention of 1912 contemplated that ship communication should be conducted either on 300 or 600 meters, an alternative of 1,800 meters being allowed under certain conditions; also marine communications grew up on 450 meters. However advisable it may then have been to have all ships on two or three wave lengths, it is certainly not practicable now. We have here an example, and it is not the only one, of the folly of putting a straight-jacket on such a rapidly growing art.
    The situation among ships to-day is much the same as existed in broadcasting at the time of the last conference, when all stations were trying to operate on 360 or 400 meters. The outstanding achievement of that conference was the adoption of the idea of giving to each station, so far as possible, an individual wave length. If our ships had a class of equipment which would allow it, I am not at all sure that a similar plan could not be worked out for them with separate wave lengths assigned to separate groups or classes of vessels. I fully realize that this can not be done at once. I know the financial and other difficulties that stand in the way of better apparatus. I believe, nevertheless, that some way should be found to encourage improvement and likewise to make the better equipment freely and reasonably available. Meanwhile some consideration should be given to a method of temporary relief. The question is one of relation. If there are not enough channels to provide all that both the marine interests and the broadcasters may legitimately desire, there must be an accommodation between them, giving to each as much as possible with due regard to the other. Possibly additional wave lengths above 600 meters may be assigned for marine use. Moreover, we must strive to get the marine signals of 300 and 450 meters out of the public broadcasting band so as not to interfere with broadcasting. I commend the subject to your careful attention.

OUTSIDE  SOURCES  OF  INTERFERENCE

    I have not attempted to list all the subjects that may come before you, but have merely referred to a few which seem most troublesome from the administrative side. One matter that must be dealt with sometime, but over which there is no means of control at present, is the interference from nonradio sources. We listeners have all experienced frequently and to our great disgust the squeals and roars which we are told come from electrical devices of various sorts in which there is no purpose to cause audible disturbance. The department has received a vast number of complaints based upon trespassing noises of this character. It is hard to trace them to their source and difficult to deal with them when found. Some branch of our radio industry certainly should investigate and study them. Harmonics, too, are troublesome. It is useless to assign a station to a definite wave length if its signals go out not only on that one but on three or four others. Our amateurs, who make by far the largest element in the radio family outside of the listeners as a whole, are particular sufferers, since the harmonics from many stations have an especial tendency to invade the amateur band. Accurate and sharp transmission must be insisted upon.

AMATEURS

    Nor have we overlooked in these previous conferences the voice or interest of the amateur, embracing as he does that most beloved party in the United States--the American boy. He is represented at this conference, and we must have a peculiar affection for his rights and interests. I know nothing that has contributed more to sane joy and definite instruction than has radio. Through it the American boy to-day knows more about electricity and its usefulness than all of the grown-ups of the last generation. I have during the past year somewhat extended this wave band. I hope that this conference may dismiss the objections that have been raised to this action.

COOPERATION  OF  THE  DEPARTMENT

    The officials of the Bureau of Navigation, which has direct charge of administrative features and full familiarity with the entire situation, are ready to give you the benefit of their information and advice.
    The Bureau of Standards has prepared a report on many of the technical phases which will come before you, and its personnel and facilities are at your disposal. The interdepartment radio committee has done preparatory work, and its members will, I am sure, be glad to cooperate with you in the consideration of all matters which have a governmental bearing. The supervisors of radio from all districts of the country are in attendance, with first-hand information as to conditions, and their knowledge, based on actual experience in the field. In short, the Department of Commerce is at your command. I believe that your membership includes every angle of radio interest. I look forward to your conclusions as a great step in the development and progress of the industry.

CONCLUSIONS

    In conclusion, I can only repeat what I have said on these occasions before--that it is our duty as public officials, it is our duty as men engaged in the industry, and it is our duty as a great listening public to assure the future conduct of this industry with the single view to public interest. The voluntary imposition of its own rules and a high sense of service will go far to make further legislation or administrative intervention unnecessary. Indeed, it will contribute enormously to the development of the art if in this stage of its infancy we can annually secure such adjustments by voluntary action as will protect public interest. We shall then have evolved a unique chapter in the development of public utilities.
    The two past conferences have been successful in these purposes and with only slight modifications made necessary by changing conditions the department has been able to follow their recommendations in the performance of its duties, and the industry has supported and conformed to these recommendations cheerfully and uncomplainingly although at some self-sacrifice. It is my ideal and yours that this new great implement which science has placed at the disposal of our people shall be developed and expanded in such fashion as to bring the maximum good, and that we may avoid any complaint from our successors that on one hand we sacrifice public interest or on the other we in any way dim that fine sense of initiative and enterprise in our people that is fundamental to all advancement in our Nation.
    I congratulate the conference on the spirit shown in the past, and I know you will enter upon your new deliberations in the same attitude.

2.  ORGANIZATION  OF  THE  CONFERENCE

                    HERBERT  HOOVER, Secretary of Commerce, chairman
                    LAURENS  E.  WHITTEMORE, general secretary

SUBCOMMITTEE  NO.  1:  GENERAL  ALLOCATION  OF  FREQUENCY  OR  WAVE-LENGTH  BANDS

W. D. Terrell, chairman.
J. F. Dillon, secretary.
Maj. L. B. Bender.
C. B. Cooper.
George S. Davis.
Dr. J. H. Dellinger.
Lloyd Espenschied.
Leo Fitzpatrick.
Dr. A. N. Goldsmith.
A. H. Halloran.

|  Prof. L. A. Hazeltine.
|  J. V. L. Hogan.
|  Prof. A.  N. Kennelly.
|  F. A. Kolster.
|  L. L. Lee.
|  W. G. Logue.
|  E. F. McDonald, jr.
|  Capt. Ridley McLean.
|  H. P. Maxim.

SUBCOMMITTEE  NO.  2:  ALLOCATION  OF  FREQUENCY  OR  WAVE-LENGTH  BANDS  TO  BROADCASTING  STATIONS

Dr. George K. Burgess, chairman.
S. W. Edwards, secretary.
R. Asserson.
Edgar L. Bill.
H. E. Campbell.
John Campbell.
A. H. Dyson.
W. E. Downey.
Dr. A. N. Goldsmith.

|  L. B. Henson.
|  J. V. L. Hogan.
|  C. W. Horn.
|  Lambdin Kay.
|  S. M. Kintner.
|  Jos. Knowland.
|  Elam Miller.
|  Adam Stein.
|  W. A. Wheeler.

SUBCOMMITTEE  NO.  3:  GENERAL  PROBLEMS  OF  RADIO  BROADCASTING

Gen. George O. Squier, chairman.
E. A. Beane, secretary.
Earle C. Anthony.
E. H. Armstrong.
R. G. Callvert.
L. M. Clausing.
James Cleary.
Powel Crosley, jr.
A. E. Davies.
C. E. Erbstein.
Herbert Frost.
W. E. Harkness.

|  Prof. C. M. Jansky, jr.
|  A. Atwater Kent.
|  H. R. Kibler.
|  Paul B. Klugh.
|  Arthur H. Lynch.
|  F. H. McDonald.
|  E. B. Mallory.
|  David Sarnoff.
|  John Shepard, 3d.
|  W. A. Strong.
|  G. D. Wardrop.
|  W. A. Wheeler.

SUBCOMMITTEE  NO.  4:  PROBLEMS  OF  MARINE  COMMUNICATION

Wallace H. White, jr., chairman.
Arthur Batcheller, first secretary.
C. C. Kolster, second secretary.
E. B. Calvert.
C. B. Cooper.
George S. Davis.
Lloyd Espenschied.
F. A. Kolster.

|  L. L. Lee.
|  W. G. Logue.
|  Capt. Ridley McLean.
|  J. L Preston.
|  E. J. Simon.
|  A. J. Steelman.
|  T. M. Stevens.
|  Lieut. E. M. Webster.

SUBCOMMITTEE  NO.  5:  AMATEUR  PROBLEMS

H. P. Maxim, chairman.
R. Y. Cadmus, secretary.
E. H. Armstrong.
Zeh Bouck.
Prof. C. M. Jansky, jr.

|  Dr. C. B. Jolliffe.
|  Jos. H. Montgomery.
|  P. C. Oscanyan, jr.
|  C. H. Stewart.
|  K. B. Warner.

SUBCOMMITTEE  NO.  6:  INTERFERENCE  PROBLEMS

Maj. L. B. Bender, chairman.
T. G. Deiler, secretary.
A. M. Caddell.
W. J. Canada.
Dr. J. H. Deilinger.
Prof. L. A. Hazeltine.
J. V. L. Hogan.

|  S. M. Kinter.
|  F. A. Kolster.
|  Elam Miller.
|  H. C. Moore.
|  O. C. Roos.
|  W. D. Terrell.

SUBCOMMITTEE  NO.  7:  INTERCONNECTION

Judge S. B. Davis, chairman.
O. R. Redfern, secretary.
L. Ainsworth.
E. C. Anthony.
S. E. Baldwin.
James Cleary.
Alfred H. Dyson.
Prank W. Elliot.
Geo. C. Furness.
Jos. S. Gettler.

|  R. B. Hale.
|  W. E. Harkness.
|  Lambdin Kay.
|  C. W. Horn.
|  D. S. Knowlton.
|  E. B. Mallory.
|  H. E. Metcalf.
|  David Sarnoff.
|  Adam Stein.
|  W. A. Strong.

SUBCOMMITTEE  NO.  8:  COORDINATING  COMMITTEE

Herbert Hoover, chairman.
W. Van Nostrand, jr., secretary.
Earl C. Anthony.
E. H. Armstrong.
Maj. L. B. Bender.
Dr. George K. Burgess.
George S. Davis.
S. B. Davis.
Dr. J. H. Dellinger.
S. W. Edwards.
W. E. Harkness.
Prof. L. A. Hazeltine.
J. V. L. Hogan.
Prof. C. M. Jansky, jr.

|  Prof. A. E. Kennelly.
|  Joseph Knowland.
|  F. A. Kolster.
|  Capt. Ridley McLean.
|  E. B. Mallory.
|  Hiram Percy Maxim.
|  Elam Miller.
|  John Shepard, 3d.
|  Gen. Geo. O. Squier.
|  C. H. Stewart.
|  W. D. Terrell.
|  K. B. Warner.
|  Wallace H. White, jr.

3.  FINAL  RECOMMENDATIONS

To the Hon. HERBERT  HOOVER,
            Secretary of Commerce, Washington, D. C.
    The Third National Radio Conference respectfully submits its report to you upon its deliberations:
    The conference convened at Washington on October 6 and has been in continuous session until to-day (October 10). The work was divided among subcommittees upon important subjects, and the recommendations of these subcommittees have been coordinated into a whole, and they are submitted herewith as the unanimous report of the conference.
    The conference has kept constantly before it the thought that its only purpose is to devise ways for the betterment of all phases of radio and the elimination of all possible impediments to its full realization of public service. The art is one of continuous flux due to the rapidity of progress through scientific discovery and invention. It requires constant revision in the relationships between its different members and in the relationships of the Government in its regulation. We have given consideration to the progress of development and to the needs of the service.
    For better understanding of the reports upon special subjects, which are necessarily of a highly technical character, the following summary of the outstanding recommendations is given:

PUBLIC  BROADCASTING

    The great problem in broadcasting is that of interference. It may arise in several ways, either by direct interference of one station by another, because of too close proximity of frequency, interference by radiotelegraph signals, or interference from outside electrical sources.
    In dealing with the first of these causes the conference has been successful in providing additional channels so that stations may not conflict with one another. To accomplish this, the present broadcasting band has been extended so as to include all frequencies from 550 to 1,500 kilocycles (wave lengths from 545 to 200 meters). Furthermore, a new system of zoning has been worked out by which it is possible to obtain still additional channels. The net result will be that instead of a number of frequencies now used by general broadcasting stations there will be an increase of 30 possible channels, bringing the total up to 100.
    In order to do away with the interference with broadcasting by radiotelegraph code signals used chiefly in marine communication, the conference recommends that 1,000 kilocycles (300 meters) which falls within the above band be discontinued for marine use, this frequency being left exclusively for broadcasting; 667 kilocycles (450 meters), which up to a short time ago was likewise used for marine communication, has already been discontinued. The conference recommends that 500 kilocycles (600 meters), which is close to the upper end of the broadcasting band, be limited to distress signals and used as a calling wave, which means that general marine communications will not be carried on at this frequency. This effectually clears the broadcasting band of code signals.
    As to interference from outside electrical sources, the conference took affirmative action in recommending that there be general cooperation with the producers and users of electrical energy by which this interference is now caused. The conference is glad to be able to say with very few exceptions there has been manifested the greatest desire on the part of such interests to minimize this interference.

DESIGNATION  AND  ALLOCATION  OF  STATIONS

    The conference recommends a new classification for stations.
    Present class B stations are hereafter to be known as class 1; class A stations as either class 2 or 3; and class C stations to go either into class 1, 2, or 3, according to their character.
    The conference recommends that the class C stations still remaining on a frequency of 833 kilocycles (360 meters) be assigned new frequencies (wave lengths). This, of course, does not mean the abolition of class C stations, but merely that instead of all of them operating on one wave length, as at present, and interfering with each other they shall have separate assignments and be distributed through the broadcasting band.
    The details as to the allocation of frequencies or wave lengths to the particular stations under the new zoning system are being worked out by a continuing committee in cooperation with the radio supervisors of the various districts. The report will be completed within a few days.
    The marine communication interests willingly accepted the recommendation of the department for the abandonment of their use of 667 kilocycles (450 meters). Their representatives at this conference should receive our thanks for the fine spirit of cooperation they have shown in further removing their operations from the broadcasting band.

MARINE  RADIO  SERVICE

    While providing additional channels for broadcasting, the conference has been able likewise to provide additional channels for marine use. This has been done by specifically designating for ship communication the frequencies of 343, 410, 425, 454 kilocycles (wave lengths 834, 731, 706, 660 meters) with 500 kilocycles (600 meters) as a calling and distress wave. This provides five channels instead of the two now in use and means a vast improvement in the present congestion near our coasts, while at the same time the interference with broadcasting will be, it is hoped, largely eliminated.
    The questions of reports giving the positions of ships was considered by the marine communication committee. It declined to recommend the prohibition of free "TR" reports, but indicated its approval of the voluntary efforts to reduce the number of unnecessary reports. The action was taken in the hope that it would eliminate interference much complained of by broadcasting stations.

AMATEURS

    The conference has allocated to amateurs substantially the same frequency bands that are now in use, with some minor changes in their location. The temporary allocation of frequencies above 2,000 kilocycles (below 150 meters) made by the department to the amateurs some months ago is given definite approval with some slight changes in the bands. The net result of this is to give to amateurs an increase over what they had at the end of the conference a year ago and to allow them a much greater area for operation.

CENSORSHIP

    The conference thoroughly discussed all angles of program directing and heard a great many arguments on this important subject. As a result it recommends that the policy of the department of noninterference in programs sent out by broadcasting stations should be upheld. Any other attitude would necessarily involve censorship in some degree.

INTERCONNECTION

    The interconnection of stations so as to provide for simultaneous broadcasting has been the most important development of the last 18 months. It has now made possible a wide extension in knowledge of national events. It means a vast improvement in program. It makes the talent of our great cities available everywhere. It has reached the point where a few stations are now thus interconnected as a matter of routine and regular procedure. There have been very recently several actual demonstrations of the possibility of nation-wide simultaneous broadcasting by interconnection. The conference affirmatively finds that simultaneous broadcasting of national events is to-day practicable over a large portion of the United States. It believes that nation-wide broadcasting by interconnection of stations deserves every encouragement and stimulation, and to that end recommends the appointment by the Secretary of Commerce of a continuing committee which will give consideration to the working out of the necessary plans for its full accomplishment.

HIGHER  POWER  FOR  BROADCAST  STATIONS

    Some confusion has arisen from the general use of the term "higher power," while, as a matter of fact, there is a sharp distinction in its significance in two entirely different fields--one the increase in power in all stations and the other the so-called "super-broadcasting" stations.
    The conference has been impressed with the necessity of placing broadcasting upon such a basis that it may be of continued service at all times of the year and all times of the day its signals reaching with proper intensity and clarity all classes of people. We must have at all times a special thought for the owners of small sets and for those whose homes are far from great centers of population. The true mission of broadcasting will not be realized until its service is available to each one of them at all times, as it is now available in our larger cities. It has been conclusively demonstrated by experimental work during the past year that only by the use of higher power can static and other kinds of interference be overcome, and that some general increase over the 1,000-watt limitation now imposed is therefore very desirable. This is especially true as to transmission during the summer and day time. Many listeners have crystal sets, and many located in the agricultural regions, who are largely dependent upon radio for their immediate contact with the markets, weather reports, and news, are not now able to receive such signals continuously. In order that they may have a continual and dependable service, an increase of power should be allowed to the stations upon which they are dependent, with due regard to distance and interference with other stations.
    This, however, presents entirely different considerations from those involved in the so-called "superpower" stations which contemplate the use of power up to 50,000 watts. The conference has been strongly urged to recommend the abolition of all limitation on power, but it refuses to do so. There has been no experience in this country and little anywhere else in the world with broadcasting by stations of such power. In the absence of actual knowledge of their effect or usefulness, the conference refuses to recommend any authorization of the general issue of licenses for stations of this character. The conference does recommend that experimentation should be allowed but that this experimentation be carried on under strict limitation, so that it be without interference with the service of any other stations or with the reception now enjoyed by listeners. Only after such experiments have been made will it be possible to determine whether such broadcasting will interfere with the existing system or whether it will be in the public interest. The conference is unalterably opposed to any monopoly in broadcasting.

FURTHER  APPROPRIATIONS  FOR  THE  DEPARTMENT

    The funds appropriated for the enforcement of the radio law by the department have become wholly insufficient. The inspection districts are so large and radio activities within them have multiplied so rapidly that it is a physical impossibility for the inspectors to cover their districts in the most efficient manner. Complaints come to them from all parts of the district which require their personal attention. We strongly recommend to Congress an increase in the appropriations made for the enforcement of the radio laws by the Department of Commerce.

DETAILED  REPORTS

    The detailed reports upon special subjects are submitted herewith.

4.  REPORTS  OF  SUBCOMMITTEES

SUBCOMMITTEE  NO.  1:  GENERAL  ALLOCATION  OF  FREQUENCY  OR  WAVE  LENGTH  BANDS

    The committee recommends the allocation of the frequency bands for the various radio services as indicated in the following table.
    In submitting this recommendation the committee appreciates that the allocations as recommended must be considered to some extent temporary or experimental on account of the absence of an international agreement relative to frequencies above 2,000 kilocycles (wave lengths below 150 meters).
 
Frequency or wave band allocations
KilocyclesMetersService
95-1203,156-2,499  Government, CW and ICW, exclusive.
120-1572,499-1,910  Marine, CW and ICW, exclusive.
157-1651,910-1,817
{Point-to-point, CW and ICW.
Marine, CW and ICW.
165-1901,817-1,578
{Point-to-point, CW, ICW, spark.
Marine, CW and ICW.
190-2301,578-1,304  Government, CW and ICW, exclusive.
230-2351,304-1,276  University, college, and experimental, CW and ICW, exclusive.
235-2501,276-1,199  Marine, phone, nonexclusive.
2501,199  Government, CW, ICW, nonexclusive.
250-2751,199-1,090  Marine, phone, nonexclusive.
2751,090  Government, CW, ICW, nonexclusive.
275-2851,090-1,052  Marine, phone, nonexclusive.
285-5001,052-600  Marine and coastal, including radio compass and radio beacons.
500-550600-545  Aircraft, CW, ICW, phone and fixed safety-of-life stations, phone, exclusive.
550-1,500545-200  Broadcasting services, phone, exclusive.
1,500-2,000200-150  Amateur, CW, ICW, phone.
2,000-2,250150-133  Point-to-point, nonexclusive.
2,250-2,500133-120  Aircraft, exclusive.
2,500-2,750120-109  Mobile.
2,750-2,850109-105  Relay broadcasting, exclusive.
2,850-3,500105-85.7  Public service.
3,500-4,00085.7-75.0  Amateur and Army mobile.
4,000-4,50075.0-66.6  Public service and mobile.
4,500-5,00066.6-60.0  Relay broadcasting, exclusive.
5,000-5,50060.0-54.5  Public service.
5,500-5,70054.5-52.6  Relay broadcasting, exclusive.
5,700-7,00052.6-42.8  Public service.
7,000-8,00042.8-37.5  Amateur and Army mobile.
8,000-9,00037.5-33.3  Public service and mobile.
9,000-10,00033.3-30.0  Relay broadcasting, exclusive.
10,000-11,00030.0-27.3  Public service.
11,000-11,40027.3-26.3  Relay broadcasting, exclusive.
11,400-14,00026.3-21.4  Public service.
14,000-18,00021.4-18.7  Amateur.
16,000-18,00018.7-16.7  Public service and mobile.
18,000-56,00016.7-5.35  Beam transmission.
56,000-64,0005.35-4.69  Amateur.
64,000-infinity4.69-0  Beam transmission.

    In the above connection the committee unanimously recommends that the Department of Commerce no longer require ship or shore stations to be equipped to send or receive on a frequency of 1,000 kilocycles (wave length of 300 meters).
    Except for the bands designated as nonexclusive, Government stations shall use only the bands designated by the Third National Radio Conference as "Government" for strictly Government business, and only the bands not so designated for public service; that is, commercial or non-Government business. It is recognized that there will have to be occasional exceptions to this rule in the course of operation of particular stations. Thus, Government stations in Alaska which handle almost exclusively non-Government commercial business will not be expected to shift to Government frequencies when occasional strictly Government messages are handled.
    Another exception to the foregoing principles is also allowed in connection with Government mobile radio equipment for training purposes. It may be used to a limited extent and subject to the following restrictions, outside the bands reserved for the exclusive use of the Government. For such training and operation uses on frequencies between 500 and 1,000 kilocycles (wave lengths between 600 and 300 meters) they will be used in the following manner:
    The officer in charge of military or naval radio operations will confer with the Department of Commerce supervisor of radio in the locality where interference is probable to determine the frequencies which may be used with least interference. Naval and military operations will then be confined, so far as possible, to the time periods, frequencies, and power which will cause minimum interference in the locality. It is understood that military and naval operation in this band will in general be limited to an antenna radiation of 75 meter-amperes, to daylight hours, and to a limited number of hours per week and weeks per year. This frequency will differ somewhat in different parts of the country.
    It is understood by the committee that the departments of the Government are authorized to utilize the frequencies above 2,000 kilocycles (waves below 150 meters), with due regard to the authorized use thereof by other services as determined by reference to the Department of Commerce.
    It is further understood with reference to the use of frequencies above 2,000 kilocycles (wave lengths below 150 meters) that the allocation thereof to a Government department for service analogous to any of the above shall be in all respects identical with other assignments.

SUBCOMMITTEE  NO.  2:  ALLOCATION  OF  FREQUENCIES  OR  WAVE  LENGTHS  TO  BROADCASTING  STATIONS

    The present general organization of broadcasting stations is considered satisfactory. A number of changes of detail are included in the following recommendations with a view to making fuller use of the frequencies available for broadcast service. These recommendations assume a frequency range for broadcasting from 550 to 1,500 kilocycles (545 to 200 meters). Without making radical changes, the recommendations group stations somewhat in the order of the effect they produce on the radio audience. The present class B group is assigned to substantially the same frequency band as at present, but the availability of the frequencies in this band is materially increased, mainly through the proposed elimination of the class C. By a modified zoning plan, which experience has shown to be desirable, improved conditions in the matter of interference should result. The stations which will go into class 2 (a part of the present class A), which render a high class of program though not in general up to the standard of the first class, are to be benefited by the recommendations, since the number of stations in this class is very materially reduced by the removal to a third class of the strictly local stations of very small power. A frequency assignment which is believed to be sound is proposed for the three classes.
    For reasons which will appear more fully in the following it is recommended that the names of the classes of stations be changed from the letter designations, class B, class A, etc., to the number designations, class 1, class 2 and class 3. Class 1 will correspond to the present class B. This nomenclature will have the advantage that the stations of highest power and, generally speaking, highest quality transmissions will be given the natural designation of class 1.
    No change is proposed in regard to the "broadcast development" class of stations. There are at present only two such stations; they are considered as experimental, and there seems to be no good reason to change their requirements or to attempt to fit them more closely into the general scheme of broadcasting stations than at present.
    It is recommended that the Department of Commerce set a time (November 15 tentatively suggested) after which no licenses of the present class C (833 kilocycles, 360 meters) will be renewed. This will make possible a very material gain in the number of channels available for class 1. Only one frequency between 790 and 870 kilocycles (380 and 345 meters) is at present assigned. Furthermore no frequencies above 970 kilocycles (309 meters), except one assigned a few days ago, are now assigned to class B stations. In view of the contemplated further elimination of ship transmissions on 1,000 kilocycles (300 meters), it will be possible to assign class B frequencies up to a considerably higher limit.
    It is recommended that broadcasting stations be divided into three classes, as follows:
 
ClassKilocyclesMetersNumber of
channels
1550-1,070(545-280)53 plus 10.
21,090-1,400(275-214)32.
31,420-1,460(211-205)5.

    It should be noted that this involves little change from the assignment recommended last year for class 1 (old class B). The upper limit for class 1 is here made 1,070 as compared with 1,040 for the old class B stations. While there is thus an extension of only 30 kilocycles to this band, it will in the future be possible to use the whole band, and a very great increase in the number of channels in the band thus becomes available. The reasons why such an increase is desirable will be more fully set forth below. There are, for the reasons earlier mentioned, only 37 channels (bands 10 kilocycles wide) in class 1 (old class B) now actually used. The above recommendation provides 53 satisfactory channels. It is also recommended below that the frequencies used in the present zone 1 on the eastern coast of the United States be duplicated in zone 6 on the western coast, thus giving 10 channels which are in effect distinct additional channels.
    The above recommended frequency limits involve practically no change in the number of channels available for class 2 stations (old class A), there being 32 channels as against 31 channels heretofore.
    It is recommended that all broadcasting stations which use less than 100 watts power be assigned frequencies in class 3. This provision should result in great improvement in the service rendered by class 2 (old class A) stations, since they will be relatively free from local interference produced by the stations of very small power which, on the average, furnish a grade of program which is of only local and limited interest.
    It is recommended that manufacturers and organs of publicity make a concerted effort to make the higher frequencies of class 2 and those of class 3 actually available to the public through encouragement of the design and use of receiving sets which include this range. It is possible by the use of various expedients to reach these frequencies with most of the receiving sets in use. It would, in addition, be highly desirable that manufacturers so design receiving sets that the higher frequencies will be less crowded together on the dials.
    Returning to the question of the class 1 stations, the considerable number of additional channels have been provided in view of three considerations: (a) Provision should be made for the operation without interference of stations of corresponding qualifications in this same frequency band in Canada, Cuba, and Mexico; (b) a large number of additional class 1 stations are now under construction and proposed; (c) some extension of this band is possible through the extension of the whole broadcast band from its former upper limit of 1,350 kilocycles (222 meters) to 1,500 kilocycles (200 meters).
    It is recommended that in a given locality not more than two class 1 stations be licensed on a given frequency. This will require that no station be required to divide more than half the time. Any additional applicants should be temporarily assigned to frequencies in the class 2 hand until a vacancy is available There is no question as to the authority of the Department of Commerce to select the frequency upon which a station should operate. Since in the plan proposed there are 63 class 1 channels, there would thus be a maximum possible of 126 class 1 stations.
    It is recommended that a revised zoning plan be adopted. The zoning scheme adopted last year was sound in principle, and the plan herewith proposed is simply a modification such as the actual development of broadcasting stations has shown to be desirable. It contemplates the establishment of a sixth zone on the west coast which shall use identically the frequencies used in zone 1. Such duplication of frequencies has been in part put into practice by the Department of Commerce, and experience has shown that because of the distance and the difference in time the plan is entirely practicable and should be extended to the whole sixth zone. This plan will have particular advantage for the west coast because if there should be in the future greater congestion of stations it would be possible to utilize in addition some of the zone 2 frequencies. The other zones can not benefit in this manner. The plan retains all of the principles of the present class B assignments; that is, the 50-kilocycle separations in each zone and the minimum of 20 kilocycles separation between stations in adjacent zones. The only change made in respect to the existing assignment of station frequencies is the drawing of the zone lines in such a way as to more nearly equalize the distribution of frequencies to the several zones.
    It is believed that there is no way to provide for more class 1 station frequencies or for a better distribution of them so as to lessen interference other than the provision of additional channels and the modification of the zoning arrangements along lines such as are proposed herein. Both of these recommendations will require some changes in the frequencies of class 1 broadcasting stations. Such changes are inevitable, but the reassignment should be made with a view to minimizing the changes required for all stations. It is recommended that a small continuing committee designated by the conference to remain in Washington and collaborate with the radio supervisors in a reassignment of the broadcasting station frequencies in accordance with the foregoing principles.
    On the question of frequencies to be used by broadcasting stations to be licensed to operate on higher power than now prescribed, the following recommendations are made:
    In licensing stations on higher power than now permitted it is recommended that the Department of Commerce utilize in zones 2, 3, 4, and 5 any of the frequencies assigned to the class 1 stations
    Assignments of class 1 frequencies or wave lengths to stations granted an experimental license to operate on higher power than now prescribed, located in zone 1, to be made only for five frequencies 100 kilocycles apart; that assignments of class 1 frequencies or wave lengths to stations granted an experimental license to operate on higher power than now prescribed, located in zone 6, be made only on five frequencies or wave lengths 100 kilocycles apart; and that the two series of five frequencies or wave lengths each in zones 1 and 6 be staggered.

SUBCOMMITTEE  NO.  3:  GENERAL  PROBLEMS  OF  RADIOBROADCASTING

    After three extended sessions of your subcommittee No. 3 in regard to the general problem of radiobroadcasting due consideration has been given to the class of programs which are to be broadcasted from various stations. After an extended discussion on the details of making recommendations to the conference it has been deemed advisable that the Department of Commerce, as in the past, take no steps to regulate the material broadcast from any station in the country, as it is believed that each station desires to cover a certain field and to entertain or educate a certain class of people. To regulate the programs under these conditions would mean censorship, therefore official censorship is not recommended.
    In regard to the changing of the requirements for operators' licenses, it has been recommended by the committee that the present experiment and instruction grade of license be made more elastic.
    It has been deemed advisable that the operators employed at broadcasting stations throughout the country should not be required to secure the same class of license as that required for marine communication. The present so-called marine license provides that the holder have a thorough knowledge of all modern systems of radio communication, and as radio broadcasting and the apparatus pertaining thereto is a science within a science, this committee recommends that a new class of operators' licenses be created, different from the license required of other types of service, and the examination for this license be based upon the needs of the entire radio broadcasting service.
    The question of so-called "superpower" or increased power for broadcasting stations has been considered in detail, and this committee has decided: "To determine the advisability of permitting the expansion of broadcasting by the employment of increased power beyond that prescribed in the regulations for class B stations and to permit the use of apparatus for this purpose to any applicant and to remove certain limitations now prescribed for class D stations, and for the purpose of observing what interference, if any, might result in public broadcast reception in the various localities this committee recommends that a new class of license be established, and that licenses in this class shall be granted by the Secretary of Commerce, who shall have discretionary power to prescribe the type of apparatus, location, frequency, power, and requirements of operation of such stations, and that licenses for such stations shall be granted on an experimental basis only, and for such period or periods of time as the Secretary of Commerce may determine."

SUBCOMMITTEE  NO.  4:  PROBLEMS  OF  MARINE  COMMUNICATION

    The committee has given consideration to the problems of marine communication committed to it by the conference and has made distribution to various marine services of the bands of frequencies (wave lengths) allocated for these purposes by committee No. 1.
    It recommends that these frequencies (wave lengths) should be distributed in the following manner:
 
120-190 kc. (2,500-1,578 meters).Were left unassigned, except as hereinafter stated, with the recommendations that allocations to the various marine services be made by the Department of Commerce.
        160 kc. (1,874 meters)
        175 kc. (1,713 meters)
        185 kc. (1,621 meters)
For Governmental use. It was recommended that the wave length of 1,620 meters be used for ice-patrol broadcasting and for other navigational aid messages, but that neither of the three wave lengths should be exclusive.
235-285 kc. (1,276-1,052 meters).For marine radiotelephony. It was recommended that specific allocations within this band should be made by the Department of Commerce and pending further developments should be tentative only.
343 kc. (875 meters)
410 kc. (731 meters)
454 kc. (660 meters)
For ship-to-ship and ship-to-shore communications.
425 kc. (705 meters)It was recommended that ships now on 705 meters be transferred to the other assignments within a reasonable time.
300 kc. (1,000 meters)For radio beacon, with a guard band of 125 meters below (to 343 kc.) against broad emissions and nonsimple harmonically modulated CW and of 52 meters above 1,000 meters (to 285 kc.). An exception of the 952-meter wave length assigned to Government use was approved. Where CW and simple harmonically modulated CW are employed, the 1,000-meter wave should be guarded by a frequency separation of 15 kc.
315 kc. (952 meters)For Government use.
375 kc. (800 meters)For radio compass, with a guard band of 70 meters below (to 411 kc.) and of 70 meters above (to 345 kc.) 800 meters against broad emissions and nonsimple harmonically modulated CW. Where CW and simple harmonically modulated CW are employed, the 800-meter wave should be guarded by a frequency separation of 15 kc.
445 kc. (674 meters)For Government use upon aircraft and submarines, on CW, and ICW.
500 kc. (600 meters)For calling and distress signals and messages relating thereto, exclusive.
2,500-2,750 kc. (120-109 meters)For mobile marine services.

    The question of decrement was considered, and upon motion it was voted to be the sense of the committee that in considering frequencies (wave lengths) of coastal stations a definite assignment of decrement for transmitters be fixed, beginning at 0.1 for higher frequency ranges (shorter wave lengths) and tapering to 0.08 for lower frequency ranges (longer wave lengths), and that the value of the decrement should be determined and assigned at the time the frequencies (wave lengths) were allocated to particular stations.
    The committee made no definite assignment of frequencies (wave lengths) to coastal stations, but upon motion voted the sense of the committee to be that such assignments should be made by the Department of Commerce and that in such assignments, and also in the assignments of the frequencies (wave lengths) lying between 300 and 500 kilocycles (1,000 to 600 meters) for ship-to-ship and ship-to-shore service, the specific frequencies (wave lengths) recommended by the committee should be varied as circumstances and conditions should, in the judgment of the Secretary of Commerce, warrant.
    The committee considered the question of the international abbreviations provided for in the London convention. It was believed that additional abbreviations should be made available immediately to American ships, and on motion the committee voted it to be the sense of the committee that two signals "QSYL_ _ _ _meters_ _ _ _" "Listen for me on _ _ _ _meters," and "QSYA_ _ _ _meters_ _ _ _" "Answer on_ _ _ _ meters" should be used, and that the entire question of the international abbreviations should be committed to the Department of Commerce for consideration and for such recommendations to the Berne bureau and to any international conference hereafter held as it might deem advisable.
    The question of "TR" reports was brought to the attention of the committee. After discussion the committee, on motion, voted that it noted with approval the recent voluntary action in reducing the number of unnecessary TR reports, and recommended that such reduction be carried as far as possible. Following this motion it was voted that the transmission of such reports should be limited between 7 p. m. and 11 p. m., shore-station time, to cases of emergency.
    The question of interference with broadcasting by harmonic radiation from various types of transmitters was discussed. It was voted that all CW and ICW transmitting sets for marine use on frequencies greater than 300 kilocycles (below 1,000 meters) should be so constructed and operated as to be substantially free from such harmonic radiation.
    The question of the standards to be maintained in the issuance of operators' licenses and in particular the standards for commercial radio operators on shipboard was considered. The committee voted to recommend that the Department of Commerce make a study of this subject and report during the coming year.

SUBCOMMITTEE  NO.  5:  AMATEUR  PROBLEMS

    Subcommittee No. 5, amateur problems, has met and, being advised of the allocation of frequencies for amateur use by subcommittee No. 1, has considered amateur problems involving subdivision of types of transmitting apparatus and also various amateur technical problems.
    We have found that most of the problems confronting the amateur are disciplinary in character and can best be handled within the amateur organization with the assistance of the chief supervisor of radio.
    The committee has voted unanimously to recommend to the conference the following:
    1.  That the use of receivers capable of radiating be discouraged for use on the short wave relay broadcast bands.
    2.  Except in the case of transmitters using coil antennas or loops, the use of circuits loosely coupled to the radiating system, or devices producing an equivalent effect, shall be required in all amateur transmitters.
    3.  All of the amateur bands shall be open to telegraphic communication effected by means of tube transmitters or devices producing an equivalent effect, excepting those using outright forms of ICW by mechanically interrupting one of the radio-frequency circuits.
    4.  A band of 1,670 to 1,760 kilocycles (170 to 180 meters) shall be assigned nonexclusively to amateur radiotelephones and ICW stations which employ apparatus in which one of the radio-frequency circuits is mechanically interrupted.
    5.  The question of issuing one amateur station license which will permit of the use of all amateur wave bands is to be left to the discretion of the chief supervisor of radio.
    6.  The international intermediates that have been in use by the amateurs of the various nations in their international amateur radio communications and which were established unofficially by the American Radio Relay League should be continued, and it is requested that this matter be taken up by the Department of Commerce with the International Bureau at Berne to the end that they may be brought to the attention of the next International Radiotelegraphic Convention for official confirmation.

SUBCOMMITTEE  NO.  6:  INTERFERENCE  PROBLEMS

    The subcommittee on interference problems has given consideration to the subjects referred to it by the conference, together with others suggested by members of the committee itself, and submits the following report:
    1.  The sources of possible interference to radio reception which were considered are:
    (A)  Electrical devices other than radio transmitting stations.
    (B)  Radiating receiving sets.
    (C)  Spark transmitting sets.
    (D)  Arc transmitting sets.
    (E)  Broad band emission and harmonics.
    (F)  Variation from assigned frequency.
    (G)  Use of unnecessarily high power and careless testing.
    (H)  "Superpower" broadcasting stations.
    These subjects will be considered in the order named.
    (A) Electrical devices other than radio transmitting stations.--The National Electrical Light Association, through a radio subcommittee of its inductive coordination committee, has been making a study of reported cases of interference with radio reception where electrical devices or supply circuits appear to be involved. A report of this subcommittee is printed in the National Electrical Light Association Bulletin for August, 1924.
    It is recommended that the conference membership generally agree to cooperate with the National Electrical Light Association in the collection and publication of information which will assist in locating the causes of interference of this nature and in reducing or eliminating the radiation from electrical equipment and appliances.
    Much of the work in mitigation of such electrical interference results in an improvement in the operation of the electrical devices or supply lines and is thus a double gain. There are, however, some electrical devices which, even when in perfect working order, cause disturbances which result in interference with radio reception. In many cases it is possible to provide filters, shields, chokes, etc., either at the source of disturbance or at the receiving set which do much to relieve the difficulties. It is felt that every possible encouragement should be given to the organized technical study of these disturbances and to the publication of information as to satisfactory methods for minimizing such interference.
    Part of the disturbance from electrical devices is practically inevitable and must be regarded, like atmospheric disturbances, as part of the inherent limitation of radio reception. In other words, the limitation upon radio reception is not only the distance and the power of the transmitting stations and the sensitiveness of the receiving set, but also the omnipresent background of slight electrical disturbances which drown out signals below a certain intensity. This background of electrical disturbances is the underlying reason why reception from local stations is inherently superior to reception from distant stations.
    The ratio of signal energy to the energy of other electrical disturbances present is of first importance in this regard, and it is to be expected that the tendency toward higher power stations will have considerable effect in reducing instances of interference.
    Much has been done in developing a measuring technique for locating and analyzing disturbances. The use of an exploring loop has proved essential. In the efforts to locate sources of disturbances it has been found important to use methods which will discriminate between effects arising from highly damped impulses and low frequency disturbances.
    Such disturbances may be divided into two main heads--(1) momentary changes of electrical conditions producing a surge or swing of potential and (2) continuous cyclic disturbances due to induction.
    It is of interest to call attention to the similarity of some of the disturbances in the first class above given to those known as atmospherics of the "rolling" or "grinder" types. It may be generally stated that any amelioration of static reactions in a receiver will usually show an improvement in immunity to momentary disturbances from sudden neighboring discharges, even of a continuous nature.
    Radiations from X-ray or violet-ray machines act like those from sparking commutators, but normally operating mercury arc rectifiers, except when starting, do not seem to produce any disturbances. Preliminary investigations on S-tubes seem to show the same result.
    Poorly bonded trolley tracks have also proved a source of trouble, but the remedy is self-evident and quickly applied, as it is a part of the routine replacements necessarily made from quite other considerations.
    In the second class we have a more or less continuous disturbance which may be produced by induction from telephone ringing machine, light, power, and electric railway lines.
    Continued and more extended cooperation between the Bureau of Standards, power, telephone, and railway utilities and the radio supervisors is recommended.
    (B) Radiating receiving stations.--A detriment to radio reception is interference from radiating receivers. No type of receiver necessarily radiates of itself, but certain types may do so when improperly constructed or operated. These are types in which local oscillations either are produced continuously or may occur temporarily during adjustment. Even these types will not radiate when the oscillation is prevented from reaching the antenna circuit by the interposition of a one-way repeater tube, and they will ordinarily radiate too weakly to cause considerable interference when used in conjunction with a coil antenna instead of an open antenna.
    It is recommended that manufacturers and home builders take steps to eliminate or at least minimize interference, particularly as follows:
    (a) Particularly for receivers to be used in congested areas, preference should be given, as far as permitted by conditions of economy and convenience, to receiver types which can not radiate or can radiate only weakly.
    (b) Receivers which continuously oscillate should be provided either with means for preventing the oscillations from reaching the antenna circuit or else with a coil antenna, or with both.
    (c) Receivers which may oscillate temporarily during adjustment should be arranged so that such oscillation can readily be avoided by proper manipulation. It is further recommended that the Department of Commerce, through its own publications and by continued cooperation with radio magazines, newspapers, and other publishing agencies, conduct a campaign of education directed to the owners of receivers which can radiate, instructing them in the nature of the interference which they cause and in the proper methods of operation to minimize or eliminate the interference.
    (C) From spark transmitting sets.--The interference resulting from the use of damped wave transmitters has long been serious and almost came to be regarded as inevitable. It has been recently determined, however, that improvements can be made in this class of transmitters which materially reduce their decrement and consequently the interference resulting from their use. From consideration of interference alone it would be desirable if all damped wave transmitting sets were superseded by continuous wave transmitting sets, but it is recognized that such action can not be expected in the near future from considerations of economy alone. If the number of damped wave transmitting sets can be gradually reduced and the remaining transmitting sets of this class gradually improved in the quality of their emission, the situation will be much improved with little hardship to the owners of such stations. With a view to initiating such a policy the following recommendations are submitted:
    (a) That in the future land stations in point-to-point service, other than those using CW, shall be limited to the use of waves of low equivalent decrement such as are produced by ICW installations.
    (b) Whereas the national law of 1912 prescribed for damped emissions a decrement not exceeding 0.2 and whereas improvements in the radio art since that date have made it possible to reduce this decrement considerably, it is now recommended that mobile installations should have decrements not exceeding 0.14, and that coastal installations should have decrements not exceeding 0.10.
    (c) The committee urges and strongly recommends that a reduction of the decrement in waves emitted by damped wave transmitters be progressively reduced as soon as practical below the limits recommended in the foregoing resolution and to the lowest practicable attainable values. It is further recommended that the next radio conference establish still lower values of decrement as appear suitable in view of progress and practical use of damped wave transmitters.
    (D) Arc transmitting sets as generally employed in the past are productive of interference by reason of the spacing waves employed, their numerous harmonies, and parasitic radiation. Means have been developed in recent years to reduce the interference from these causes in arc transmitters to a point where they are no longer objectionable and at a reasonable expense. It is the sense of this committee that arc transmitters should be so equipped and so operated as to minimize or eliminate harmonic radiation, parasitic radiation, fluctuation of fundamental frequency, and spacing wave radiation, inasmuch as all of these constitute sources of interference.
    Spacing waves result in practice only from arc transmitters in which two frequencies of oscillation are employed--one while the key is depressed and one when the key is open. The former provides the desired agency for signal transmission and the latter is ignored by the receiver. The spacing is just as productive of interference as the signal wave, however, and its use constitutes an economic use of the available band. Means have been developed for absorbing the energy of the converter in a local circuit, so that no energy is radiated except when the key is depressed. This arrangement has been successfully applied to arcs up to 200 kilowatts in size, and there is little doubt but that it can be applied also to the largest sizes, although it involves considerable expense. It is recommended that the principle of a single working frequency for each complete transmitting system at any station (transmitting sets plus power equipment plus antenna) be generally adopted and rigidly adhered to. If that be done, the spacing wave will be automatically forced out.
    (E) Broad band emission and harmonics.--The width of frequency band emitted by a transmitting set varies from the extreme of a spark transmitting set on one side to the practically fundamental frequency of a key-modulated continuous wave tube transmitting set, which is not forced to extreme output. Between these extremes lie the emission from arc transmitting sets, audibly modulated tube transmitting sets, and telephone transmitting sets. Although some of the interference from this source results from inherent characteristics of the apparatus used, much results from the use of apparatus purposely designed to emit bands sufficiently broad to be easily picked up by simple detectors as in the case of interrupted or audibly modulated continuous wave sets. Untrained operators, unsuitable receiving apparatus, and unstable transmitting systems are some of the reasons why audible modulation of CW transmission is employed. The same reasons can be advanced to justify spark transmission. Obviously, the use of any system of radiotelegraph transmission which becomes audible only by detection and amplification requires a broader band than a system which requires heterodyning for audibility and is an uneconomical use of the available radio spectrum. The number of stations which may work without interference in the bands at present commonly employed can not be much increased unless broad band emission is relinquished in favor of pure continuous wave radiation. If any means can be found in addition to economic necessity to encourage the more general use of pure wave radiation for radiotelegraphy, it ought to be vigorously applied. Exception can well be made in favor of transmitting apparatus used for calling and distress only.
    Interference from harmonics results from the emission of radio power on one or usually several frequencies higher than the fundamental frequency, but at less intensity than the fundamental. Any transmitting set, including tube transmitters, is subject to this fault if oscillating directly in the antenna circuit, and tube transmitters show the same tendency in addition when pushed to maximum output. The trouble can be practically overcome by the use of master oscillator-power amplifier systems and greatly improved by the use of loose coupling between oscillating and radiating systems. An effective remedy is so comparatively simple and inexpensive that it ought to be compulsory. If the principle of licensing a station to use only one frequency per complete transmitting system were rigidly applied, stations radiating harmonics could be dealt with because they are actually radiating appreciable power on frequencies other than that for which licensed.
    Harmonics of the carrier wave of stations operating in the lower frequency range of the broadcast band, or in the marine frequency band, will fall within the range of the broadcast frequency band, and under certain conditions will prove to be a serious cause of interference. It is recommended that all possible steps be taken to minimize this trouble by technical means well known to the art and by careful supervision on the part of the radio supervisors.
    In the marine telegraph service the substitution of tube transmitters for spark equipment greatly reduces interference, particularly where the CW system is employed. The use of modulated CW signals, while less productive of interference than spark equipment, is not recommended except where absolutely necessary.
    (F) Variation from assigned frequency.--There are two classes of troubles from this source--that resulting from intentional unauthorized change and that resulting from unintentional variation. The former is much too prevalent. It is a common occurrence to find a station shifting to an unauthorized frequency owing to temporary interference or trouble with apparatus at the assigned frequency and then remaining there indefinitely if any advantage, real or fancied, is found. Government as well as commercial stations are guilty of this practice; possibly the former more so. In many eases the offending station is causing unknown interference to many others, although its own individual situation may be improved.
    It would be desirable if some sort of penalty could be provided for this practice applicable both to Government and commercial stations. Military and naval operators can be reached through disciplinary methods, but civilian operators of the Government departments are not so easily disciplined. Commercial operators can be reached through their licenses. It is recommended that steps be taken to provide definite discipline for offenses of this character. It is felt that a better check on the use of unauthorized frequencies should be provided and that regular measurements and reports be made of the frequencies actually used by radio transmitting stations throughout the United States. It is believed that work of this character is a proper duty of the Department of Commerce radio service. If, however, the Department of Commerce is unable to undertake more extended work of this kind at the present time, it is urged that as a temporary measure cooperative arrangements be made by that department with other organizations operating radio stations, by which a systematic check may be obtained on the frequencies used by radio transmitting stations during the course of their operation.
    Variations from assigned frequency through unsuspected changes in the transmitting apparatus is frequent but not often of great importance because the variation is usually comparatively small. Nevertheless, frequency allocations have been made on the basis of narrow margins between adjacent stations and this calls for maintenance of frequency within the closest possible limits. Progress in the design of measuring equipment and in the provision of standard frequencies has been rapid, and we recommend even more stringent regulations than now exist, coupled with the utmost zeal on the part of the Department of Commerce in the enforcement of the regulations on maintenance of assigned frequency.
    (G) Use of unnecessarily high power and careless testing.--Unquestionably much interference now experienced is the result of using higher transmitting power than necessary. There is a noticeable tendency to provide sufficient power to maintain communication under unfavorable conditions and then to continue with that power through all the more favorable seasons. Control of power input necessarily rests usually with the operating personnel, and few operators will voluntarily reduce power for the possible accommodation of remote stations not in a position to make their troubles known directly. In fact, the use of sufficient power to get every signal through clearly without necessity for repetition is probably more conducive to reduction of interference than the use of less power which results in repetitions, and thereby consumes more time than necessary in clearing traffic. The happy medium between maximum power and insufficient power can only be achieved by constant supervision of operations by the responsible management assisted so far as possible by the inspectors of the Government. It is a very difficult situation to control by Government inspectors alone and the burden must be assumed primarily by the managements of stations.
    Careless testing.--Interference from this source is similar to that from the use of excessive power in that it is usually under the direct control of an operator without due appreciation or respect for the rights of others. Much testing can be conducted without radiating power, and if testing with radiation could be confined to the actually necessary cases the interference from the source would probably be negligible, particularly if testing were conducted on the authorized frequency of the station. Care on the part of responsible managements that their operators are properly instructed in testing methods, combined with vigilance and report to supervisors on the part of all cognizant of such abuses, are about the only remedies which can be suggested.
    For reporting cases of interference to station owners or to the Department of Commerce it is recommended that use be made of a form which gives complete details such as the attached form of the Interdepartment Radio Advisory Committee.
    (H) "Superpower" broadcasting stations.--Considerable fear exists among broadcast listeners and owners of existing broadcasting stations that the use of appreciably higher power in broadcasting stations over that now permitted may adversely affect the reception of a large number of listeners. The benefits to be gained by the general public from such action seem, however, to warrant the development of such a service in an experimental way, subject to careful observation of results and its cessation if the benefits expected are not attained without equal detriment in other directions. By reason of the lack of data in this field it seems unwise to limit this experimental work by restrictions on the power employed, the variation power with seasons or hours of the day, or the progressive use of increasing power as results seem to warrant. It does appear essential, however, to locate such stations at such distance from populous centers that such centers will not be subjected to intensity of signals in excess of that now produced by authorized stations in their midst. From such data as are now available it is believed this object will be attained if the station is so located with respect to populous centers that the distance between it and the boundary of such community will not be less than the quotient obtained by dividing the product of antenna current in amperes times effective antenna height in meters by a constant tentatively set at 100. Experience may make it advisable to modify this constant, but it seems sufficiently conservative to serve for the initiation of this experimental work.
    2.  Radio communication, both in broadcasting and in the message-transmission fields, has made great strides in the past four years. The Bureau of Navigation of the Department of Commerce, in whose hands lies the regulation of radio, has accepted the tremendous task imposed by the growth of the art and has executed its trust with an admirable spirit and efficiency that is appreciated by all workers in the field. The extensions of the past year, however, have made increasingly evident the fact that the Bureau of Navigation is handicapped in its radio activities and that without further personnel and funds it will have grave difficulty in supervising the conduct of radio. Among the matters of growing importance that require increasingly close, attention by the bureau are:
    (a) Observation of interference caused intentionally.
    (b) Determination of interference caused by accidental shifts of wave frequency.
    (c) Determination of improper radiation of harmonic and parasitic waves, that may cause interference.
    (d) Frequent inspection of radio stations and checking of their facilities.
    Therefore, it is the sense of this committee that the Bureau of Navigation be encouraged and aided in its activities by more liberal appropriation of funds.
Report of radio interference and violations of radio laws and regulations
(Check appropriate item in each group and forward to.............................)
 
STATION  PARTICULARS
Offending stationStation communicating
with offending station
Reporting station
Call letters  
Name  
Frequency (kilocycles)  
      (Observed.) (receiving wave interfered with.)
Wave length (meters)  
      (Observed.) (receiving wave interfered with.)
System employed:  
      Spark  
      Arc  
      Tube, CW  
      Tube, ICW  
      Tube, phone  
Approximate location  
TIME  AND  NATURE  OF  INTERFERENCE  OR  VIOLATION
Interference Law or regulation violated
___ Off of assigned wave.DateSec. _ _ of ship act of 7/23/12.
___ Traffic not authorized on this wave.TimeSec. _ _ of radio act of 8/13/12.
___ On assigned wave but interfering.____ GMT.Article _ _ of London Radio Convention of 1912.
___ Broad wave.____ Eastern.Article _ _ of Service Regulations of London convention, 1912.
___ Arc mush.____ Central.Section _ _ of Radio Regulations of U. S. Dept of Commerce, edition Aug. 15, 1919.
___ Poor modulation.____ Mountain.Supplementary Radio Regulations of U. S. Dept. of Commerce, dated _ _ _ _ _ _ _.
___ Harmonics.____ Pacific.Is interference or offense satisfactorily covered by law or regulation?  Yes.  No.
___ Frequency varies.  
___ Compensating wave.How often does offense occur? 
RECEIVING  SET  USED  BY  REPORTING  STATION
NAME-PLATE  DATA  
Receiving set.____ Single circuit.____ Crystal detector.
 ____ Two circuit.____ Vacuum tube detector.
Detector.____ Regenerative, nonoscillating.____ Number of stages of radio-frequency amplification.
 ____ Regenerative, oscillating.____ Number of stages of audio-frequency amplification.
Amplifier.____ External heterodyne. 

[Extract from communication causing interference or violation]

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_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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    Call letters of other stations in vicinity which may have heard this interference or violation
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Remarks
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_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
    I hereby certify the above to be a true copy and to represent, to the best of my knowledge and belief, an accurate and full account of what occurred.
    Dated_ _ _ _ _ _ _ _ _ _ _ _ _, 19_ _.
 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
(Officer in charge of station.)

    This information will be helpful in improving traffic handling and operating conditions for both the reporting and the interfering stations. Prepared by Interdepartment Radio Advisory Committee, Washington, D. C.


SUBCOMMITTEE  NO.  7:  INTERCONNECTION

    Your committee appointed to study the problems of interconnection, both as to wires, radio, or other means, has established certain existing facts and conditions and recommends a definite procedure.
    We repeat the remarks of the Secretary, that improvement in programs is essential, and that such improvement is more readily accomplished through the use of interconnecting means between broadcasting stations, bringing the programs of the larger centers of art, music, and events of public interest to the more remote broadcasting stations.
    A brief history of the developments of interconnection of broadcasting stations is believed illuminating and essential as a premise on which to offer a constructive recommendation.
    The use of wires in interconnecting broadcasting stations grew out of a desire on the part of program managers to introduce into their programs events which could not be brought to the studio. The first notable use of telephone wires over any appreciable distance was between Chicago and New York when the Princeton-Chicago football game, played in Chicago in the fall of 1922, was broadcast from a station in New York.
    Coincidentally, the first use of telegraph wires to bring a program to a broadcasting station was in the fall of 1922, when the world series, played at the Polo grounds in New York, was broadcast from a station in Newark, N. J.
    At about the same time the first experiments in radio interconnection were undertaken between Pittsburgh and Cleveland; but, being distinctly experimental in character, no definite requirement was met and no definite schedule arranged.
    The first systematic interconnection of broadcasting stations by space radio was inaugurated in September, 1923, between Pittsburgh and Hastings, Nebr., this interconnection being accomplished without interference to other broadcasting stations or other radio services by means of short wave transmission.
    In the case of wire interconnections the earlier service was limited to supplying a program to one distant station over a limited distance, but this means of interconnection has since been expanded to include stations from New York to San Francisco and as far south as Habana, Cuba, and from 1 to a total of 18 broadcasting stations simultaneously providing the same program or public event.
    By means of radio interconnection programs produced in this country have been transmitted to England and South American countries where wire line interconnection was impossible. The programs transmitted on short waves were picked up and broadcast by long waves, in some instances, with the assistance of wire interconnection, by from two to eight stations. This development was notable in several respects:
    First. The programs were internationally available, as European listeners had no difficulty in picking up and listening to the British stations.
    Second. This was an example of a combination of wire and radio interconnection.
    Third. This international distribution of a program was accomplished without interference to other radio services. It should be mentioned that various stations in the United States also picked up this transmitted program and rebroadcast it for general distribution over the United States.
    Another notable example of development of international interconnection by radio occurred recently, when the Firpo-Wills contest, obviously of intense interest to Argentina, was broadcast from the ring side in the usual manner, employing wire interconnections from the ring side to the broadcasting station at Pittsburgh and transmitted by short wave radio to South America, where the words spoken by the announcer at the ring side were received and rebroadcast.
    The first radio interconnection of more than two broadcasting stations occurred in 1923, when the speeches at a dinner in New York City were picked up and delivered to a local New York broadcasting station, which transmitted the program on its customary wave length. Simultaneously, this program was conveyed to Schenectady over telegraph wires and broadcast on both short and long waves. The short wave was picked up at Pittsburgh and again rebroadcast on short and long waves. This short-wave transmission was picked up at Hastings, Nebr., and rebroadcast on its usual long wave; and in the final step, Oakland, Calif., picked up the Hastings transmission and rebroadcast on its usual long wave.
    At present certain telephone and telegraph wire facilities are available and in use. As examples, the Boston studio and the Springfield station are interconnected by means of telegraph wires; a station in New York and a station in Schenectady, and likewise stations in Washington and New York, are similarly connected by telegraph wires. This service is now in daily use, and programs are broadcast simultaneously from these interconnected stations. On numerous occasions within the last year events of public interest, two of the most recent being the National Defense Test Day exercises last month and the address of the Secretary of Commerce at the opening of this conference this week, have been distributed to over a dozen broadcasting stations by means of telephone wires. These speeches and exercises were thus made available to all radio listeners throughout the United States.
    Great strides have been made in the development of the interconnection of broadcasting stations, nationally and internationally, by means of telephone or telegraph wires and radio, or combinations thereof. With certain limitations, facilities are now available and in use in serving a large portion of the United States, and it is anticipated that regular service of this character may be available to a sufficient number of stations in prominent centers in the near future to provide improved programs to a large portion of the country. It is felt that interconnection by these various means still presents many problems, and to encourage further development of these facilities your committee recommends that a continuing committee be appointed by the Secretary of Commerce to carry on the study of this development.
    We have considered the suggestions made as to the advisability of cooperative action among the broadcasting stations looking to better programs, the handling of national events, the making available to local stations of the talent of great artists, and the hearing of important events occurring at a distance. All this involves the physical problem of interconnection, and, of equal importance, financial questions, such as the expense of the interconnection, the source of revenue, the payment of artists, and those arising from differences in time which affect simultaneous broadcasting and in some instances will require a sectional rather than a national view. There are many other features which necessarily arise when cooperative action is attempted. Manifestly it has been impossible for our committee to undertake any final determination of such matters. The feasibility and advisability of such a plan must be determined principally by the broadcasters themselves.
    The suggestion of such coordinated effort, whether through the formation of an association or otherwise, deserves thorough consideration requiring much more time than your committee can give it. We recommend that the entire question be referred to the continuing committee already suggested.
    We listened with great interest to the remarks of Capt. P. P. Eckersley, of the British Broadcasting Co., and particularly to his suggestion of the possibility of an extension of the development of simultaneous broadcasting in Great Britain and the United States, making programs produced in one country available at the same time to the other. We appreciate the wonderful possibilities of such a plan and can imagine the interest with which such a development would be received by the listening public. We recommend that this suggestion also be referred to the continuing committee hereinbefore mentioned for their consideration.

5.  SUMMARY  OF  FREQUENCY  OR  WAVE  LENGTH  ALLOCATIONS
 
KilocyclesMetersService
  95-1203,156-2,499  Government, CW and ICW, exclusive.
120-1572,499-1,910  Marine, CW and ICW, exclusive.
157-1651,910-1,817
{Point-to-point, CW and ICW.
Marine, CW and ICW.
}exclusive.
165-1901,817-1,578
{Point-to-point, CW, ICW, spark.
Marine, CW and ICW.
}exclusive.
        160           1,874  Government, nonexclusive.
        175           1,713  Government, nonexclusive.
        185           1,621  Government, ice patrol broadcasting and navigational aid messages, nonexclusive.
190-2301,578-1,304  Government CW and ICW, exclusive.
230-2351,304-1,276  University, college, and experimental CW and ICW, exclusive.
235-2501,276-1,199  Marine, phone, nonexclusive.
        2501,199  Government, CW, ICW, nonexclusive.
250-2751,199-1,090  Marine, phone, nonexclusive.
        2751,090  Government, CW, ICW, nonexclusive.
275-2851,090-1,052  Marine, phone, nonexclusive.
285-5001,052-600  Marine and coastal, including radio compass and radio beacons.
        300           1,000  Radio beacons.
        315           952  Government CW, ICW, spark.
        343           874  Ship-to-ship and ship-to-shore CW, ICW.
        375           800  Radio compass.
        410           731  Ship-to-ship and ship-to-shore CW, ICW, spark, exclusive.
        425           705  Ship-to-ship and ship-to-shore CW, ICW, spark, exclusive.
        445           674  Government aircraft and submarines, CW and ICW.
        454           660  Ship-to-ship and ship-to-shore CW, ICW, spark, exclusive.
        500           600  For calling and distress signals and messages relating thereto, exclusive.
500-550600-545  Aircraft and fixed safety-of-life stations, CW, ICW, phone, exclusive.
550-1,500545-200  Broadcasting services, phone, exclusive.
550-1,070545-280  Class 1.
1,090-1,400275-214  Class 2.
1,420-1,460211-205  Class 3.
1,500-2,000200-150  Amateur, exclusive.
1,500-1,670200-180  Amateur CW, ICW.
1,670-1,760180-170  Amateur, ICW, phone.
1,760-2,000170-150  Amateur, CW, ICW.
2,000-2,250150-133  Point-to-point, nonexclusive.
2,250-2,500133-120  Aircraft, exclusive.
2,500-2,750120-109  Mobile.
2,750-2,850109-105  Relay broadcasting, exclusive.
2,850-3,500105-85.7  Public service.
3,500-4,00085.7-75.0  Amateur and Army mobile.
4,000-4,50075.0-66.6  Public service and mobile.
4,500-5,00066.6-60.0  Relay broadcasting, exclusive.
5,000-5,50060.0-54.5  Public service.
5,500-5,70054.5-52.6  Relay broadcasting, exclusive.
5,700-7,00052.6-42.8  Public service.
7,000-8,00042.8-37.5  Amateur and Army mobile.
8,000-9,00037.5-33.3  Public service and mobile.
9,000-10,00033.3-30.0  Relay broadcasting, exclusive.
10,000-11,00030.0-27.3  Public service.
11,000-11,40027.3-26.3  Relay broadcasting, exclusive.
11,400-14,00026.3-21.4  Public service.
14,000-18,00021.4-18.7  Amateur.
16,000-18,00018.7-16.7  Public service and mobile.
18,000-56,00016.7-5.35  Beam transmission.
56,000-64,0005.35-4.69  Amateur.
64,000-infinity4.69-0  Beam transmission.

    NOTE.--Further details are given in the various subcommittee reports on preceding pages.