April 1930 COWAN: TRANSOCEANIC TELEPHONE SERVICE 643

voltage regulating equipment. This latter room is RESULTSshielded in the same manner as the line terminal room The construction work on this project occupied ain the central terminal and administration building to period of about two years from start to finish. Some ofprevent radio frequency noise from this equipment the work was carried out under particularly tryingbeing radiated and picked up by the antennas. Power conditions. At times very unfavorable weather condi-and telephone connections for these buildings come tions were encountered. A considerable portion of thefrom the-central terminal building in cable. construction involved new types of plant for whichEach receiving building has three or more antennas there was neither precedent to be followed as to pro-

grouped around it, one for each wavelength received. cedure nor experience with which to establish the neces-These antennas are supported by huge wooden frame sary time intervals accurately. By careful coordinationstructures. The size of these frameworks varieswith of the work, however, the desired completion datesthe wavelength to be received. Expressed in terms of for the various parts of the project were realized. Thewavelengths the dimensions are about as follows, 1 three additional European circuits have been placed inwavelength wide, from 13 to 12 wavelength high, and service and tests are now in progress looking towards4 to 6 wavelengths long. The long axis of the structure establishing a New York-Buenos Aires circuit.is perpendicular to the direction of desired reception.The upright and horizontal members of the structureare bolted together with fish plates and strengthened Discussionby cross bracing. The entire framework is carried on TRANSOCEANIC TELEPHONE SERVICEconcrete foundations which have been made especially (MILLER, BOWN, OSWALD, AND COWAN)large to prevent the antenna overturning in high winds Bn Wf YORK, N. Y., JANUARY 30, 1930e to p t

. Bancroft Gherardi: The engineer from the very nature ofor getting out of alinement due to settling. The active his work is necessarily chiefly concerned with the technicalelements made up of copper tubes are supported on the aspects of such a question as is before us this morning, thesides of the structure with "stand off" insulators. The improvement and extension of communication service. But as

transmission lines from the antennas to the receiving engineers we don't want to have altogether out of mind the socialstations are concentric copper pipes supported about and economic results that may be expected to follow from what

we are doing.one foot above the ground by driven iron stakes. To Going back only about fifteen years ago to 1915, universalcare for expansion and contraction with temperature, telephone service did not exist even throughout theUnited States.these pipe lines are made to follow curving paths. The eastern part of the United States could not telephone to the

In addition to the regular receiving units there is western part of the United States, or vice versa. By develop-ments that had been made in the preceding few years, however,

another receiving station at the Netcong center which in 1915 the two coasts of the United States were tied togetheris provided with a receiving set arranged for accurate telephonically. So that we can really say from 1915 on we hadfield strength measurements and other radio testing within the United States and with our sister country Canada,equipment. This unit is called the Channel Observing service which extended practically wherever there were settle-Station. This station maintains a continuous check on ments of any size.

the radio transmissio conditionsandThis, however, by no means gave universal service, althoughthe radio transmission conditions and advises the New as many of you know, it has been for many years the policy andYork Control office as to the opportune time for the the aim of the Bell System to give universal telephone service sochanges in wavelength which are necessary from time that anyone at any time, could talk to anyone else quickly,to time each day. Very accurate measurements of the clearly, and conveniently.

received signals can also be made by the An enormous advance has been made since 1915. Most of

franneque ofserving station.Incase * e Europe has been brought into the picture. The possibility ofchannel observing station. In case Of interference to communicating with ships at sea has been demonstrated, and onethe telephone circuits from radio stations assigned to of our large transatlantic liners, the Leviathan, is now equippedneighboring wavelengths such measurements facilitate for the giving of commercial telephone service and has given suchthe correction of the difficulty. service on her most recent transatlantic trip.

In addition, the development in a sister art has created stillTERMINAL ARRANGEMENTS another problem for the telephone engineers. As airships have

developed the problem comes up of communicating with airships,The New York terminal of the overseas circuits is and the technical features of that problem have been solved.

located in the Telephone Building at 24 Walker Street, Mr. Miller has told you some of the proposed extensions ofwhich building is also the long distance office serving intercontinental service which are under way. I do not think hethe greater part of the New York metropolitan area. mentioned the fact that a station is planned and under way on the,"1T ., . . I -I.I I . 1 Pacific Coast looking toward the West and doing our part in

The pecil teminaing nd estig eqipmet islo-making it possible to communicate with the Islands of thecated on the twenty-fourth floor of this building. There Pacific and with the Continent of Asia. So it is not going too farare at present eight units which are used for the various to say that the scientists, the research experts, and the engineersoverseas services, four being used for the short wave have done their part to render universal telephone servicesystems we have been considering. Fig. 10 shows a practicable, and that the applications have gone a long way to

of theequipment in this room~.Frm h make such service a reality. Mr. Miller mentioned the fact thatportion today from New York City or any other place in the Unitedterminal room the circuits go to the long distance States or Ca,na,da,, it is possible to communicate with about 85 perswitchboard where the operators are located, cent of all the telephones in the world.

644 COWAN: TRANSOCEANIC TELEPHONE SERVICE Transactions A. I. E. E.

After these connections are made other problems will remain If, as I presume, these disturbances are definitely connectedto be solved, but they will not be the problems of the engineer. with the disturbing forces we observe, it seems to me that a needThey will be problems of a social nature. I will mention but two of closer cooperation between our scientific people interested inof them. One arises from the fact that the world is approximately the transmission of electrical energy and the astronomers isspherical in shape and that therefore when in some parts of the indicated.world it is daytime in others it is night. We already encounter The other thing I wanted to call to your attention, because itdifferences of time between San Francisco and London of eight seems to me that it is extremely fundamental to all of our con-hours. Another hour is added to that difference in time when siderations in the development of telephone service, is certainSan Francisco communicates with Germany. underlying differences which exist between telegraph transmis-

I recently had a very interesting test conversation. I was sion and telephone transmission for commercial purposes, andlocated in New York and on a Thursday afternoon, at four p. m. certain requirements which are involved in the building up andI spoke by telephone to a man located in Sydney, Australia, giving of what we conceive to be adequate telephone service.only with him it was Friday morning at six a. m. Not only was For the most part, telegraph service is a delayed service.there a difference in hours but there was actually a difference in There may be exceptions to it, but in general it is a service whichdays. Incidentally, also, there was a difference in seasons. He involves a greater or lesser degree of delay between the filing of awas in midsummer while I was in midwinter. message and its delivery to its recipient. That being so, addi-

There is no doubt whatever that the difference in time will tional and possibly erratic delays may not be of great moment.furnish a certain limitation on the use of telephone service under This tends to minimize the deleterious effects of the delays duecertain conditions, but I have no doubt that in many cases the to fading or static.

On the other hand, telephone service in its ideal form is for theservice will be so valuable to meet the desired needs of the users athat the difference in time will be overcome. It is interesting to most part, a no-delay service, and the ideal telephone servicenote that on the transatlantic telephone service we have service would be one in which anyone desiring to speak to anvone else,practically all hours of the day and night, showing that if people could do it, as Mr. Gherardi indicated, easily, satisfactorily,*11 1 *11- . 1 ~and economically at anv time he so desired.want to talk badly enough they will be willing to talk even in theearly hours of the morning. If that is the ideal, and I think it is, then any factors which

.-Theotherdifficulyisthlanguaediffiulty.Ohave to do with erratic delays are highly objectionable.The other difficulty iS the language difficulty. Obviously To go back, if you examine any of the applications of modern

people cannot speak to each other unless they can use the same science, yow fd atito a'l e theadegree to whichlanguage. Here, however, I feel we are going to have some help they a,re used a,nd the degree to which they have become anfrom another sister development of recent years, in which the ithe part of our social an buines s te, isclosely

Bell Telehone Labratorieshave hadan imporan patntegral part of our social and business structure, is closelyBell Telephone Laboratories have had an important part. I related to their dependability, and so it is with regard to tele-

refer to the talking movies. What the ultimate outcome of thisreadtohirepnbltyadsotiswhrgrdotl-phone service. It doesn't suffice in the giving of a telephonelanguage question is I don't know, but I feel quite confident that service to be able to do it well sometimes. If telephone serviceworld-wvide telephony adds an additional incentive to those that is to be used by people for their social and business purposes as analready exist with the increase in travel that goes on year by year, integral part of their scheme of living, it requires that it should bewith the closer social connections that exist year by year through done well substantially all of the time. That is, you cannotthe different parts of the world, to the establishment of some e auniversal language, and if we get such a universal language the or anyoteform ofaenepaon integralfcservice,people who I think will have created the major demand for it will organiza,tion of his business unless he an depend on it.be the scientists, the research people, and the engineers in their Unfortunately, up to the present time, so far as the kind ofdevelopment of transportation communication and the talking telephone service we are now talking about is concerned, namelv,movies. transoceanic service, which at the moment has to be done by

F. B. Jewett: There are two things I should like to say a radio, there is not either with long waves or short waves, thatword about. The first is a brief word concerning one of the degree of reliability which would permit of the maximum de-technical problems which confront us, and the second has to do velopment of its use and the maximum incorporation of that typewith some of the fundamental factors which confront those of us of service into the social and buisiness structure of the world. Itwho would give a universal telephone service with the means that is true that by the use of a combination of long-wave trans-are now at our command. mission and short-wave multiple channel transmission, such asMr. Bown in his remarks referred to difficulties in the radio we have had here described to us, we are approximating to that

transmitting medium which were presumably connected with degree of reliability, but we are still somewhat in the positiondisturbances in the sun. If that is a fact, and there is every that at times people cannot use the service just as they wouldreason to believe it is, I surmise that in the years just ahead of us like to use it. It is for that reason that we have, as was indicateda great deal of useful information will be obtained by a closer in one of the papers, contemplated and are in the process ofcooperation between those of us who are interested in this sort putting in as a supplement to radio a telephone cable across theof thing and, we will say, our astronomical friends. On my Atlantic, not with the idea that it will supersede in any largereturn from Japan recently, I stopped in Pasadena for afew days, measure the traffic handled over the radio channels but that itand on one occasion when I was visiting Dr. Hale I was given a will provide an additional degree of security looking towardsmost vivid ocular demonstration of the magnitude of the the giving of continuous service, and so tend to make the thingmagnetic forces which are related to the sun spots. I had more nearly the type of plant, the type of structure which en-occasion to look at some of the spectral lines in and near one of the ables people to contemplate the use of telephone service withsun spots which was then on the fa,ce of the sun, a, sun spot many equanimity and sulrety.times the size of the earth, which indicated magnetic forces in this In the radio side itself, and contemplating its future develop-vast electromagnet comparable to and possibly many times ment as it pertains particularly to telephony, we are of coursegreater than any magnetic forces which we can produce even confronted with all of the difficulties that have been mentioned,artificially on earth. The lines of the solar spectrum in and at and also with the fact that the increasing demand for radiothe edges of the sun spot were split apart in the so-called Zeeman- channels for all kinds of purposes is eating into what now appearseffect manner, to a degree which I had never seen in a laboratory to be a limited supply of the available channels. What thehere on the earth, indicating a magnetic disturbance of a magni- future has in store for us with further research and developmenttude which was beyond our conception. work, particularly in the very short wavelengths, of course

April 1930 COWAN: TRANSOCEANIC TELEPHONE SERVICE 645

nobody can say, but it is quite clear that whatever extension One thing more. Mr. Gherardi and Dr. Jewett referred in athere may be to the number of available channels, that number very interesting way to the language question which, of course, isis still pretty small, and if reliable telephone service across great important sociologically. I should like to ask a question as tostretches of water can be established in one place, the demand for what the percentage of telephone communications, roughlya large number of channels may increase to an embarrassing speaking, has been in regard to distribution among the languagesextent, so that it is incumbent upon the scientists and engineers of the world, and what the indications are in regard to the diffi-to do everything they can, not only to conserve what we now culties of telephonic communication upon a language basis.have, but also to extend the range of availability of channels. G. W. Kenrick: Dr. Bown and Dr. Jewett have both em-

It seems to me from what little, I know of the work as to both phasized the complexities and importance of radio transmissionradio telephony and radio telegraphy, that every step we are phenomena in transoceanic telephony; students of radio com-making at the present time to the better utilization of what we munication are hence confronted with the problem of determininghave is tending to an enlarged use of what is available. The what type of experiments are best adapted to gaining informationimprovements which have here been indicated, and many others which will enhance its reliability. There are several methods ofwhich have not been indicated, are all tending to make for a more investigation which may be utilized. The most obvious andefficient use of these channels, but there is still a very large perhaps most widely employed method has been to observe theamount of work to be done. actual communication efficiency of the circuit, (i. e., articulation,

I merely mention these points because they tend to amplify intelligibility, frequency characteristics, etc.). This gives us awhat Mr. Gherardi said, that over and beyond the purely very good index as to the value of the channel under observationtechnical problems there are some controlling problems in- at the particular time of the tests. Unfortunately, however,herent in the social and business life of the world which determine this method may not be best adapted to indicating what willto a very large extent not only the course which our development happen to the channel tomorrow, and it is only by a long series ofwork should take but place definite limits on the things we can consistent observations that some indication as to its actualor eannot do. reliability may be obtained.

A. E. Kennelly: There is one point in the remarks made by Such observations always run the risk of neglecting long-timeDr. Jewett that I should like to emphasize, namely, the rela- variations such as those associated with the eleven-year sun spottively close dependence between radio communication and solar cycle which has been shown to have an important correlation withactivity. It seems that we are dependent upon the sun not only magnetic disturbances. It therefore becomes of interest tofor our beneficent conditions of warmth, food, and life, but also evolve experimental methods which will serve to separate thefor maintaining in satisfactory performance our long-distance various causes of the transmission phenomena in order that theyradio communication. may be separately studied and appropriate means adopted for

During the last year, the Eiffel Tower has, I believe, issued their successful elimination where they are undesirable.every day at eleven-twenty Greenwich mean time, a meteoro- In addition to the regular measurements of field strengthlogical bulletin which is followed by a series of brief remarks already indicated, there are other methods of investigation whichconcerning cosmical disturbances that have an influence upon are very interesting and which I think will play an increasinglyradio communication, namely, sunspot activity, magnetic important part in future investigations of radio transmission.activity, the earth's atmospheric electrostatic activity, and also Notable among these is a method evolved by Breit and Tuve, ofseismometric disturbances. That service is part of the regular the Department of Terrestrial Magnetism, and also used bymeteorological bulletin. Unfortunately, we don't often hear the Heising of the telephone group and numerous other investigators.Eiffel Tower across the Atlantic, but we are informed that the In this method a signal in the form of puLlse of very short durationFrench Government is about to repeat this daily radio-cosmic (in the order of 10-i seconds) is transmitted. This pulse inbroadcast from two of its radio stations simultaneously, com- general travels from the transmitter to the receiving point by amencing at 20.00 Greenwich mean time, namely Lafayette, on a number of distinct paths through the upper atmosphere (sup-wavelength of 16,900 meters, and Issy-les-Moulineaux, on a posedly corresponding to a series of rays multiply reflected fromwavelength of 32.5 meters. the earth's surface en route). At the receiving point the re-

The Scientific Union of Radio Telegraphy, or the U. R. S. I., sponses to this single pulse due to signals arriving over theseis much interested in this and similar subjects relating to the several paths may be separated by the variable time delays theypropagation of electromagnetic waves over the surface of the have encountered and the transmission along individual paths,earth, and it seeks by a special liaison committee to develop a hence studied separately.system through meteorological bulletins, of rapid intercom- The importance of this method of investigation lies in the factmunication concerning disturbances, whereby radio observers that the effects produced by components of the received signalmay not only be able to forewarn as to possible suspensions of arriving over the various paths are separated and hence sus-communication but also through collection of statistics, indicate ceptible of individual investigation, whereas measurements oftheir influence upon transmission. field strength alone (or of transmission characteristics) give only

It is quite possible that in the years to come, such communioa- the results of the syntheses of the transmission arriving over thesetions may be of great scientific value in addition to their com- several paths. Thus, signals arriving by various paths maymunication importance, but I merely wish to point out that combine in such a manner as to produce selective phase interfer-information concerning magnetic disturbances and sun-spot ence at the receiving point, and important distortion doubtlessdisturbances have, at the present time, a certain commercial results from this cause. By means of multiple receiving antennaimportance, and a certain engineering importance, so that rays, however, signals suffering from this type of distortion maywhat is going on in the sun has a certain dollar-and-cent value perhaps be successfully combined. Signals suffering selectivefor us to know, in relation to long-distance radio communica,tion. distortion and attenuation along a single path are, however,

I aJm mnaking a plea, therefore, for the sympa,thetic considera- much more difficult of utilization. The method described istion of any plans which may be fostered in this country by the helpful in furnishing further information as to what factors aremeteorological authorities at Washington, for the rapid dissemi- mainly responsible for the particular type of fading experienced.nation of cosmic information that may a,ffect ra,dio. I a,m hoping It is also admirably adapted to studies of Heaviside-Kennellythat it may be possible to do here what the Eiffel Tower has layer heights and other factors which may be correlated withalrea.dy done during the la,st twelve months, a,nd I think that we magnetic and solar elements:may hope for such extension of service from the Arlington Sta- It therefore seems that the methods outlined may be of con-tion and other radio stations in the near future. siderable helJp in the study of the problem. It remains, however,

646 COWAN: TRANSOCEANIC TELEPHONE SERVICE Transactions A. I. E. E.

for the radio engineer interested in transmission to be always on mission and reception, which are not possessed by the ordinarythe lookout for new methods which will serve to further separate polarized waves.and clarify the various agencies entering into this extremely T. G. Miller: I should just like to do what I can to answerinteresting but extremely complex problem of long distance Professor Kennelly. The nature of the business where we turncommunication. facilities over to people to talk makes it rather difficult to get the

J. J. Pilliod: When one contemplates the purchase of about statistics we should like to have. In my paper I pointed outa thousand acres of land in one site to be used as a transmitting that the statistics we had and the classifications, businiess andstation, and five hundred acres or so for a receiving station, a line social, were obtained entirely from the location of the telephonesof towers a mile or more long, 185 feet high, and other things of which were used. For that reason it is not very accurate. Wethe kind referred to in these papers, problems are encountered have no reliable information, as to the percentage using differentwhich are not to be treated lightly, and which are entirely out of languages, but unless I am very much mistaken the predominantthe range of the ordinary amateur type of radio station operation use is English. Possibly about 85 per cent of the calls are inas contrasted with what we are trying to do here of giving a English. Many of the calls from Paris and Berlin are filed byconsistent, commercial telephone service. Americans who are over there.

A. Nyman: The discussion this morning did not consider the Ralph Bown: In answer to Mr. Nyman's question, I do nottheoretical features of transmission of short waves, but it would know of any experiments which have been made with circularlybe interesting to know about the recent theories of polarization polarized transmission. Vertically polarized transmission asof radio waves and the turning of the plane of polarization. I represented by the transmission from antennas having verticalunderstand that experiments have been made to determine the elements, and horizontally polarized transmission from antennaamount of turning of the plane of polarization and, for long systems having horizontal elements, are both in commercial use.distances, considerable degree of turning from vertical to hori- Vertical polarization is used largely by American stations,zontal plane or vice versa takes place. whereas, I believe, the German stations at the present time go in

There is a type of wave known as circularly polarized and more for horizontal transmission.of a type generally attributed to light waves. It may be thought Whether the use of the kind of polarization he refers to,of as a spiral wave with the plane during 14 cycle as vertical and circular polarization, would improve transmission results, ofthe next 14 cycle as horizontal, the plane thus turning all the course must be left to experiment. Such experiments as I amtime from one plane to the other. It would be interesting to familiar with, in which attempts have been made to analyzeknow whether any experiments have been made to utilize this the distortions and the variations which occur at the receivingcircularly polarized radio wave, as it would seem that such a station, are not conclusive as to the effect of polarizationwave would possess certain advantages with regard to trans- changes.