Dell J,A6ora/Ories Record

Dell J,a6ora/ories Record

Volume Three OCTOBER, 1926 Number Two

The Evolution of the Input Transformer

By F. E. FIELD

INPUT transformers started and the input side: i.e., the receiving their history but not their pres- element of the repeater. Its function ent characteristic name with the was to connect line and repeater with- commercial installation in 1904 of out excessive transmission loss of telephone repeaters of the electro- voice currents due to unmatched im- magnetic type. Transformers of pedances, and to prevent transmis- various kinds and for different pur- sion of low frequencies incident to poses had been in use in the telephone the use of the repeater on composited system for some years. In general lines carrying telegraph signals. their function was to insulate one This repeating coil had a low ratio portion of a telephone circuit from and a low impedance. another. Thus, a toll line would be When a vacuum tube, suitable as an terminated by one winding of a trans- amplifier of voice frequencies, had former, the other winding of which been developed a need arose for a re- could be connected to the local cir- peating coil with ratios and impe- cuit. The local and long distance dances previously not required in the portions were thus insulated, but the telephone plant. And with this need speech currents in either portion there was a new emphasis upon the were, by induction, repeated in the word "input" and the introduction of other, and hence, the name of "re- the term "input transformer" to de- peating coil" for such a transformer. scribe the coil used to connect the line The ratio of the turns in the two sets and the receiving side of the repeater of windings was, of course, chosen element. with reference to the impedances of The input impedance of a vacuum the lines between which the coil was tube -that is, the impedance between to repeat. the grid and the filament -is very When the mechanical repeater was high, approaching infinity under cer- inserted in a stretch of long distance tain conditions; and a transformer circuit, a transformer called a repeat- was required to transform-i.e., "step ing coil was used between the line up" -the low impedance of the line 433}

www.americanradiohistory.com to match the high impedance of the different type, therefore, was de- tube. Development work by E. O. signed by R. L. Jones in the early Scriven was started in February, part of 1914. That transformer, 1913, toward the production of one shown in Figure 3, was of the shell with as high a step -up ratio as could type. It had less distributed capacity be obtained with satisfactory trans- than the straight -core type and there mission of voice frequencies. The was some improvement in the range design then developed had a straight of transmitted frequencies, as is shown in Figure 2 by the characteristic dated 1914. This type of transformer was used in the first demon- stration of the Transcontinental Tel- ephone Line. A considerable number of transformers of this type were built for use in the early vacuum -tube repeat- CT] ers. Difficulty was experienced, however, in their manufacture, Fig. 1- Design of 1913; size 9 by 3 inches particularly in the winding. With the in- silicon -steel core and was wound in a creasing demand for input trans- number of sections to minimize the formers it was soon desirable to re- distributed capacity, as shown in Fig- design for commercial production. ure i. Before assembly in the re- The type of structure shown in Fig- peater equipment it was mounted in a ure 4 was, therefore, evolved by W. wooden box filled with moisture - L. Casper, and the first model of a proofing compound. Its voltage -am- transformer of this design was built plification - frequency characteristic in March, 1915. It was later known is shown in Figure 2, and indicates a as the 203 -type input transformer. range of transmitted frequencies Its construction is well suited to com- wide enough for intelligible speech. mercial production; the spools and This type of transformer had a windings are readily made and the very large external magnetic field assembly of the core with the spool which proved troublesome in the op- involves very much less labor than eration of the repeater. An entirely the assembly of the earlier design.

1926 ----- ...... i.02-3 --' i 9 A ilk V `

100 1000 10000

FREQUENCY (LOGARITHMIC SCALE)

Fig. 2 -How the voltage -amplification characteristics of our transformers have been improved in thirteen years 434}

www.americanradiohistory.com From an electrical standpoint the chine. Also, the inertia of the mov- new transformer was practically the ing parts of the winding machines equivalent of the preceding design then in use was so large that wire and was entirely satisfactory for the smaller than No. 31 could not be used transmission of speech. without an excessive number of break- The 203 -type transformer, how- ages. Due to these limitations on the ever, was large, heavy and expensive. To obtain the desired transmission for voice frequencies a very high impedance was required and that meant many thousands of turns of fine insulated wire. Since the Manufacturing Department had not at that time developed the technique of winding No. 4o black -enamel insulated wire it was necessary to use much larger wire insulated with enamel and silk. The amount and kind of wire required, therefore, were directly responsible for the size and weight and much of Fig. 4-Design of 1915; size 6%4 by 454 the cost. inches In 1916 the problem of designing smaller and cheaper repeater equip- windings, an amplification as large ment placed upon the coil develop- as was desired could be obtained only ment group the necessity of develop- at a sacrifice of the low frequencies. ing corresponding transformers. In It was not desirable, however, to im- this development the use of standard pair the quality of the repeater operation in this manner. Up to that time (1916) the use for input transformers had been con- fined practically to telephone repeaters. In these, the amplification of frequencies below 135 cycles and above 2300 cycles was not desirable; in fact, it was decidedly objectionable, and means were provided elsewhere in the repeater to reduce the amplifi- The band Fig. 3- Shell -type design of 1914; size 6yß cation of these frequencies. by 4 inches of frequencies which the transformer was required to transmit was parts and standard methods of con- therefore defined at about 200 cycles struction were adhered to as far as to 2300 cycles and the trend of the possible in order to secure a low cost. development had been along the lines The toroidal construction of Figure of producing smaller and cheaper 5 was selected. The number of turns transformers rather than in attempt- of wire, however, which could be ing to extend the range of trans- wound on the core was limited by the mitted frequencies. size of the shuttle on the winding ma- Furthermore, since it was desirable

13 5}

www.americanradiohistory.com Fig. 5- Toroidal transformer, mounted on a block 6 x incites

to maintain the input impedance of A number of designs were pro- telephone repeaters approximately duced in the years 1916-1918, but only constant over the transmitted fre- two of them combined advantages of quency- range, each of the transform- cheapness and efficiency which en- ers so far mentioned was designed to abled them to survive. They are be used with a non -inductive resist- the 201 and 213 types shown in Fig- ance shunt across its windings and ure 6. Many of the amplifiers trans- the characteristics shown were taken mitted frequencies below and above under that condition. The resistance the previously adopted range of 200 also served to flatten out the ampli- to 2300 cycles, for considerable prog- fication characteristic, producing a ress was made in extending the fre- more uniform amplification over the quency range. frequency range. The progress in amplifier design Soon after the United States en- made during these years led to the tered the World War the demand decision in 1918 to improve the qual- for amplifiers of various kinds added ity of the repeaters on the transcon- a great stimulus to the development tinental telephone circuit. Since the of input transformers, especially of quality of the transmission of the the smaller and lighter types. Their voice frequencies depended largely on development required not only the so- the input transformer, that part of lution of many theoretical problems the repeater was selected as affording of design but also the development in the greatest possibility of improve- the Manufacturing Department of ment. Naturally the types of trans- the technique of winding small sizes former which were investigated were of insulated wires. This accomplish- those recently developed for small ment at Hawthorne was one of the amplifiers. Of these the 201 type was principal contributions to the realiza- selected, since it was small, inexpensive tion of small, highly- efficient input- and readily adaptable to quantity transformers. production. Furthermore, the Manu- 436k

www.americanradiohistory.com facturing Department had had ex- This transformer, as well as those perience in making this type and had mentioned later, is designed to be developed methods of winding. used without any shunt resistance and It was next evident that very little the characteristics shown for it were more could be done in reducing the taken under that condition. size of the input transformer and that Further development in the design any further improvement would have of transformers, with the object of to he in extending the frequency improving the amplification at the range or reducing the cost. Atten- lower frequencies, led to the use of tion was given to the amplification of permalloy as a core material. Also, the higher frequencies and means a further study of methods of wind- were found whereby the amplifica- ing resulted in the extension of the tion of the frequencies from 3000 to high -frequency range considerably 500o cycles, and even higher if neces- above 5000 cycles. These develop- sary, could he controlled by the use of ments have resulted in transformers certain methods of constructing the with almost uniform amplification windings. By these means it is pos- over a wide band of frequencies. sible to produce, in the frequency This characteristic, very necessary in range above 1000 cycles, an ampli- the high -quality amplifiers of the fication characteristic of practically present day, is shown under date of any shape desired and hence to obtain 1926 in Figure 2. A transformer of the approximately flat characteristic this type is the 226 -type, which is me- necessary for faithful and accurate chanically similar to the 234 -type reproduction. An input transformer shown in Figure 7, except that it has with such a characteristic is the 234 - a permalloy core. type shown in Figure 7. It has a sili- Our progress of approximately con -steel core and an improved me- thirteen years in the development of chanical structure; and it is highly input transformers is well symbol- efficient as well as inexpensive. Its ized by Figure 2, to which reference amplification characteristic is shown has previously been made. There has in Figure 2 under the date, 1923. been a steady improvement in trans-

Fig. 6 -- War babies "; 201 -type on the left and 213-type on the right

1.3 7}

www.americanradiohistory.com mission characteristic, both in fre- The developments have resulted in quency range and in voltage- amplifi- input transformers which are about cation ratio. Commensurate im- as small as can easily be handled for provements in cost, in reliability, and manufacturing purposes, .with a range in reduction of size have accompanied of transmitted frequencies adequate

tr-t rgi."1°r"iz"°r"^tcoF'1"177"1^'r-,:tzi

Fig. 7 -234 -type input transformer; an example of present -day small, economical, and efficient design the gains in transmission. Of the en- to present -day requirements, and pro- gineers concerned with coil develop- ducible at relatively low cost. Fur- ment whose studies and designs have ther progress will demand attention been responsible for these advances particularly to extending the range many names ought to be mentioned, and further reducing the cost. The particularly H. Whittle and E. L. method and technique which has been Schwartz, but space limitations pre- evolved will prove of value also in clude telling the complete history. other related developments.

www.americanradiohistory.com The Silent Drama of Telephony

By JOHN MILLS

WI iEN a motion-picture film essentially new technique had to be gets across to its audience developed to accomplish it. its photography has carried Dr. Nichols first simplified the an emotional stimulus. Of this fact physical processes which were in- The Gold Rush, The Big Parade, volved and then symbolized them. In Grass, The Last Laugh, Don 0, and the development of suitable pictorial Ile II'ho Gets Slapped, were excel- symbols and in the production of the lent illustrations. Their realism ex- picture in which these symbols vary, cited and strained the observer's emo- change, and move with an illusion of tions; they presented concrete human the physical operation of the tube it- situations, not cold abstractions. self, he was ably assisted and advised Of motion pictures, however, there as to motion -picture technique by two is another and more limited type motion -picture engineers, Messrs. which strives, not for the emotions, Arthur W. Carpenter and F. Lyle but for the intellect; and deliberately Goldman. These experts were at that deals with abstractions. This type is time on the staff of the Bray Pictures in the class of educational and so- Corporation, but later became the called "non- theatrical" pictures. active members of the Carpenter - Into this field Bell Telephone Lab- Goldman Laboratories, Incorporated. oratories entered in 1921 with the In the next entry of our Labora- production of the remarkably success- tories into this educational field these ful film The 1ludion. The scenario two experts acted as consultants and was written by the late Dr. H. W. their newly organized company per- Nichols with the assistance of J. C. formed the photographic work of Schelleng and others. The film reproducing The Electcrical Transmis- ceived a wide distribution through the sion of Speech and The Nature of Motion Picture Bureau of the West- Speech and ilndition. The first of ern Electric Company and more than these films shows the physical prin- forty prints of it have been made at ciples of speech production and its various times. electrical conversion by telephone All previous products of non -the- transmitter and receiver. The second atrical films, as far as the writer can records graphically some of the fun- learn, had been limited to the por- damental facts, derived by investiga- trayal of actions which could be tions in our Laboratories, as to the photographed. But how can one pitch and energy content of speech, photograph the operation of a vacuum as to the sensitivity of the ear, and as tube as an oscillator, a modulator, a to the intelligibility of the various syl- detector, or an amplifier? The in- labic sounds of the English lan- stinctive answer is "it can't be done." guage. An illusion had to be created; and an These two films were produced

4391.

www.americanradiohistory.com with the advice of Messrs. Snook, introductory survey of our work Fletcher, Maxfield, Frederick, Moore, which is presented to recruits from Wegel, and other specialists in the the colleges. Of the second film, material which they portrayed, and which is limited in appeal because of the scenarios followed outlines pre- its technical content, only a few prints pared by John Mills. They were have been made, but of The Electrical carried through production by P. C. Transmission of Speech over forty Hoernel who contributed several in- prints have been made. Some of these genious methods of presentation and have been purchased by telephone was responsible for coordinating the companies and the rest are kept in technical comments of the various en- circulation by the Motion Picture Bu- reau of the Western Electric Com- pany. The film on speech transmission was an experiment in visual education and differs from other films in the following way. An educational film is usually constructed by writing a logical series of titles and then illustrat- ing these titles in any way whatever which will be effective. The logical outline, therefore, inheres in the titles rather than in the pictures themselves. In The Electrical Transmis- sion of Speech, on the contrary, the logical arrangement inheres in the pictures and the titles are incidental. This idea was the outgrowth of a lecture which the writer of the scenario had given before various college classes. In that lecture a simple telegraph circuit consisting of a battery, a key, a sounder, and the connecting wires was sketched on the blackboard. For the telegraph key would then he substituted a variable resistance, which did not alter the physical relationships but meant that the modula- tion of the current, instead of being from no current to full current, was from some current to a higher value. Figure i By successive substitutions of this character the diagram was developed gineers whose work they recorded. into a carrier -current system and Both films were widely used in lec- finally a radio -telephone system, em- tures before colleges and engineering phasizing thereby the fundamental societies by G. B. Thomas and others unity of all forms of electrical com- and have since formed a part of the munication.

44 01"

www.americanradiohistory.com 'The more elementary of these steps the mouth. For the exposition of this were embodied in The Electrical idea J1r. Hoernel placed his own head Transmission of Speech. Figure i at the disposal of the photographic shows three frames of this picture experts with the result shown in Fig- where the variable resistance is re- ure 3. Finally, by the transition in- placed successively by a carbon cell dicated in F igure 4, the simple current- detecting device became an ordinary telephone receiver and the source of the sound waves delivered to the ear in Figure 5. The next film production of the Laboratories came two years later, in 1925, in a group of pictures dealing with the switching operations of a telephone central -office. This production was engineered by P. C. Hoernel and the scenario was by John Mills. Technical advice as to circuit features

Figure 2

and by the button of a telephone transmitter. The current indicator in the circuit, consisting of an electro- magnet with a spring armature, became by the addition of a mirror the moving element of an oscillograph. And this oscillograph pictured on a screen, as shown in Figure 2, sound waves of single frequency as produced by tuning forks. The oscillograph Figure 3 next showed complex waves, formed by the superposition of the waves and methods employed by operators, from two tuning forks, and how the and expert assistance in arranging ap- characteristic of a complex wave is paratus for photographic presenta- altered by resonating one or another tion, were contributed by W. H. Ben - of its components. A basis was thus dernagel. laid for the appreciation of complex The purpose of that picture was to waves, the speech significance of which show the electrical, mechanical, and is due to the resonating chambers of human operations which are per- 4411.

www.americanradiohistory.com Figure 4

formed in setting up a telephone con- of a Telephone Call. These later edi- nection between two subscribers. A tions were arranged by A. K. Aster. portion of it, therefore, was obtained Of the complete and original film some by direct photography of apparatus twelve prints are already in circula- in operation and of the actions of sub- tion and the demand is increasing. scribers and oper- In Through the ator. The re- Switchboard the mainder consisted opening scene of animated dia- shows Mr. Hart- grams showing nett initiating a the circuits and call by lifting the operations of the receiver of his relays, lamps, and telephone; and keys in the se- then it cuts to a quence in which view of our P. B. they occurred. X. where his line - The direct pho- Figure 5 lamp lights and tography was Miss Amrell made in the P. B. X. of the Labora- plugs in and answers. After the num- tories on the tenth floor and in two ber has been given it shows her oper- of the offices. ations in completing the connection The actors in this film drama were and in ringing; and then cuts to a view J. S. Hartnett, W. F. Johnson, and of Mr. Johnson receiving the call. Dorothy Amrell, who rehearsed and When the conversation terminates, posed for their respective parts with scenes show the two men hanging up all the usual surroundings of grease the receivers; the supervisory lamps paint, powder, and high -powered elec- light, and the operator disconnects. tric lights which accompany a com- The film then takes up these opera- mercial production. tions in detail. For example, the orig- The film thus made was Through inal signalling operation is shown by the Switchboard, and from it, by cut- dissolving the desk stand to show the tings and the addition of titles, and switchhook within it. The conven- some photographic material not incor- tional symbol for the switchhook is porated in the original edition, two then introduced and the circuit dia- other films were produced known as gram of the subscribers' line is built A Telephone Call and Circuit Study up. In detail thereafter the various 442}'

www.americanradiohistory.com features of the cord circuit are "ani- from this portion of the film showing mated in" and their function and conditions after the subscriber has operation indicated and related by been called and while conversation is cutting back to views of the actual taking place. The complete presenta- switchboard. tion occupies two reels. After showing in this way all the In 1926 two new films, as was pre- circuits and operations there follows viously mentioned, were made from a review in which the entire circuit this material. Of these, 'I Telephone diagram appears. The calling sub- Call omits practically all circuit de- scriber's receiver is lifted off its hook, tail and electrical operations, pictur- the switch closes, the lines in the dia- ing only the mechanical and human gram which indicate the subscriber's operations. This film is now being line are emphasized by greater bright- distributed by the Motion Picture ness; the diagram of the line relay is Bureau of the Western Electric Com- animated, its contact closes and the pany for showings in clubs, schools, diagrammatic line lamp hrightens. and Y. M. C. A's. The other film Diagrammatically also the answering confines itself almost entirely to the cord tip then moves to engage with development of the circuit and its se- the jack. The supervisory and line - quence of operations. cut -off relays are animated in proper How some of these operations are sequence, and the portions of the cir- treated is shown in Figure 8. The cuit then carrying current appear switchhook, line relay and subscriber's brighter. On the other hand the line - lamp are there paralleled by an ele- relay circuit reverts to its normal mentary diagram at the right to em- brilliancy as current in it ceases, the phasize the separate circuits and the relay opens, and its diagrammatic relay operation. lamp fades out. Ln this way the suc- The most recent production of the cessive steps in the operation arc fol- Laboratories is a portrayal of the lowed on the diagram by animation operation of the vacuum tube as a and illumination. Figure 7 is a frame telephone repeater. In the original

Fig. 6- Actors in "Through the Switchboard ": J. S. Hartnett, Dorothy ,lntrell, and W. F. Johnson

a 431

www.americanradiohistory.com vacuum -tube film, The (ludion, the dots carefully laid out by scale to the emphasis was more on radio than on required position as in Figure 9. voice -frequency operations. The pres- Many technical details of this char- ent film for its scenario follows a acter, which enhance the illusion and booklet, issued some time ago by the contribute to the accuracy of presen- American Telephone and Telegraph tation, were contributed by Joseph Company and entitled The Magic of W. Coffman and A. K. Aster. The former is an educator and motion -picture expert who recently joined the Carpenter- Goldman Laboratories. The latter, as a member of the Bu- reau of Publication of our Labora- tories, was technically responsible for the production of this picture. From the idea of wave motion of air molecules the film progresses rapidly to a corresponding wave motion of electrons in wires, and its transla- tion by a receiver into air waves. The idea of an attenuation of the elec- tronic motions in long wire- circuits is then developed and hence the necessity of a telephone repeater. At the transmitting end of the line the moving dots representing electrons are most numerous and decrease expo- nentially to the receiving end. These dots, which are animated and have different positions in successive Fig. 7 above and 8 below frames, are illustrated in one position Communication, selecting those por- by Figure io. tions which have to do with long -distance transmission by repeaters. It takes its name from that booklet with a sub -title The Telephone Repeater. This picture starts by developing a

conception of . wave motion of air molecules; and this is symbolized by thousands of tiny circles which move hack and forth on the projection screen, each with simple harmonic motion about its normal position and in such phase relations to the others Figure 9 that waves sweep across the screen. For the transmission of one wave The operation of the vacuum tube across the screen forty-eight frames as an element is then developed and are required. Each frame has i600 finally it is shown' as a telephone re- {44

www.americanradiohistory.com Figure io Figure 11 peater. First there is built up the transformer a very much larger num- idea of emission of electrons from the ber surge back and forth with the filament, then their passage to a same period as those in the grid cir- charged plate, and finally their con- cuit. A frame from this portion of trol by a grid. Successive frames in the film is shown in Figure t t. which the electrons in the connecting The film ends with a map of the wires and the tube have different United States into which are ani- positions show a periodic variation in mated by bright lines the enormous the stream through the plate circuit network of wires through which the corresponding to the surging in and American Telephone and Telegraph out of the grid circuit of a much Company and its Associated Operat- smaller number of electrons; while in ing Companies make possible its na- the secondary winding of the output tion -wide telephone service.

www.americanradiohistory.com Our New Radio Laboratory at Whippany

By EDWARD L. NELSON

RECENT noteworthy addition expansion in the receiver field, a con- to the facilities of the Labo- dition which has made it undesirable ratories is an experimental to have a test station in the heart of radio station at Whippany, New Jer- the metropolitan area. Even when sey, for broadcasting development. testing is restricted to the hours after Up to the present, the test -pro- midnight, in conformity with govern- gram activities essential to the devel- ment regulations, there are protests opment of Western Electric broad- from confirmed "DX" enthusiasts; casting equipment have centered in and no doubt many who do not take our West Street Building. Many the trouble to forward complaints ex- readers, no doubt, have had occasion perience a feeling of impatience and to listen to these "2XB" tests, which ill will toward the strong test sta- had their beginning in the autumn of tions. Further, the present tendency, 1921. Phonograph selections, the for reasons similar to those just men- usual offerings of the handful of sta- tioned, is toward the installation of tions then "on the air," constituted regular- program stations on plots the first tests. Attention was then di- outside the densely populated dis- rected to the transmission of music- tricts. This necessitates a thorough vocal, instrumental, orchestral and study of the conditions surrounding organ -as originally played. The the operation of this new type of in- extensive acoustic and telephone ex- stallation. These considerations and perience of the Laboratories aided in the fact that a high -power radio the gratifying progress made, and a transmitter is a rather undesirable standard of transmission was soon neighbor in our Laboratory where achieved which has been difficult to delicate measurements are a part of improve. This work afforded a firm the ordinary day's work, led to the foundation upon which to build, and search for a more suitable location subsequent broadcasting equipments which has culminated in the purchase have conformed to its general lines. of the Whippany property. As a result, it is possible after an in- Whippany, a small industrial com- terval of less than five years, to point munity, is approximately four miles to some 1 ço Western Electric - east of Morristown and on the equipped stations in regular opera- Mount Pleasant Road, one of the tion, most of them recognized leaders principal highways connecting with in the industry; and the number is on the Oranges and Newark. Since it is the increase. some fourteen miles from the latter, Growth in the number of transmit- and twenty -two miles from Manhat- ting stations, remarkable as it may tan, abnormally strong signals will appear, has, however, been completely not be projected into these areas. overshadowed by the corresponding The plot includes nearly fifty acres of 446}.

www.americanradiohistory.com .l "bird's -eve sketch" of the Whippany radio laboratory as it will look tchen completed grass- covered elevated land with a the mains of the local company is al- gentle slope to the east, and is but a ready on the property. The power few hundred feet from the highway. required has been contracted for with Railway transportation is afforded by the New Jersey Central Power and the Lackawanna Railroad with a sta- Light Company, which serves this tion at Morristown, from which hour- section of the country, and is now ly service to Hoboken is maintained. erecting an additional 20,000 kv -a The Whippany River Railroad, a plant on the Passaic River approxi- short line connecting with both the mately one mile from the station. Lackawanna and the Erie, passes Considering these factors, the loca- through Whippany and a switch track tion is ideally suited to our purpose. adjoins the property. On the neigh- In order that the station may he boring highway, with frequent service available in the shortest possible to Morristown, the Oranges, and time, a building already on the prop- Newark, is a bus line which will ren- erty is to he remodeled. This was der the station nearly as accessible as originally a dairy; it consists of a the Laboratories in so far as a large central portion approximately 45 feet portion of the New Jersey commuting by 8o feet including two stories and a zone is concerned. The advantage of basement, together with two two - this feature from the standpoint of story wings approximately 25 feet by the engineer with a family is evident. ioo feet. For the present, active use An adequate supply of water from will be made only of the central sec- {47}

www.americanradiohistory.com tion. The upper floor will be modi- of the activity will be transferred to fied to provide for a large operating Whippany with the object of begin- room and a laboratory approximate- ning the tests "on the air" early in ly 4o feet by 45 feet, together with a the autumn. All tests will, of course, suitable studio and control room, a be made after midnight as the sta- private office, and a general office. tion is not intended for broadcasting The lower floor will be devoted to a purposes in the accepted sense. How- power room, a storeroom, a shop, ever, since they will constitute the and a locker room. Provision for the trial runs on one of the latest devel- heating plant, fuel storage bins, and opments in the art, they probably will possibly some additional dead stor- be of interest to all radio enthusiasts. age space will be made in the base- The Department of Commerce has as- ment. The lower portion of the signed the station call letters "2XN ". building is of field stone; the second In addition to these tests it is ex- story is sheathed with shingles. Two pected that study of transmitting an- small detached buildings to the right tenna- systems for use in the broad- and left of the main structure will be casting frequency -band will consti- used as garages. When the contem- tute an important phase of the work. plated changes are completed, it is There is a rather remarkable short- expected that the space will be quite age of detailed design information in satisfactory for laboratory purposes, the literature upon this important and that the structure will present a subject. Although our experience in handsome appearance. the past few years has added con- The initial antenna system will be siderably to our store of knowledge, supported by two 25o -foot steel tow- nevertheless it is not complete and ers now under construction. These further work should produce worth- are set well out in front so that the while results. building will be away from the Other important problems will im- denser portion of the antenna field, mediately occur to the engineer who and that ample space may be pro- has given serious thought to broad- vided for the installation of an ade- casting matters. Remarkable as the quate ground system. progress of the past few years has As has been indicated, this station been, the solution of many pertinent is intended to provide facilities for questions still lies in the future, and development work in radio broad- opportunity to make suitable con- casting. The first use of the plant tact with the medium involved, that will be in connection with transmis- is, the ether, is obviously a prereq- sion tests on the 5o kw. set which uisite to success. This opportunity will be our next production in this the new station is expected to afford, field. In the Laboratories, work on and there can be little doubt that it the units for this transmitter is pro- will contribute materially to the ceeding rapidly and, as soon as the maintenance of Western Electric's building is modified, a large portion eminent position in the industry.

www.americanradiohistory.com EDGAR SEt.i)r,N BL1,c)11 Director, Bell Telephone Laboratories Recently elected President of Western Electric Company, Mr. Bloom i now becomes a Director of our Laboratories. .1 graduate of the University of Pennsylvania, from Bell System service in several operating companies and most recently as rice-President of i.ím cric au Telephone and Telegraph Company, he brings wide experience in engineering, construction, commercial and executive functions. 4 4

www.americanradiohistory.com Public- Address Systems

By T. L. DOWRY

pROBABLY all of us have at but instead of the customary single some time had the irritating ex- granular carbon button, it has two perience of straining our ears in such buttons, one on each side of the an effort, often unsuccessful, to catch diaphragm. Also the diaphragm is the words of a speaker addressing very thin, is tightly stretched, and ar- some audience of which we formed a rangements are made to damp it. part. Such occasions remind us that These special features make the trans- in most gatherings of any size the lim- mitter comparatively free from dis- itations of the unaided human voice tortion. Since this microphone is also render it difficult or impossible for a employed with our broadcasting speaker to make himself clearly un- equipment many illustrations of it in derstood by all his hearers. One of the press have made widely familiar the chief functions of our public ad- its appearance, and the screened dress systems is to overcome this ob- mounting in which it is suspended on stacle, which must have intervened springs to isolate it from vibration. between speakers and audiences since The electrical fluctuations which men first began to gather in assem- constitute the output of the trans- blies. In case the speaker has diffi- mitter are much too weak to operate culty in making his voice loud enough the loud- speaking telephones, and to carry as far as the more remote amplification is, therefore, necessary. listeners, all that is required is that The transmitter output is brought the public address system shall rein- through shielded conductors to am- force his voice sufficiently. Broadly plifiers which are practically free speaking, the public address system from distortion over the frequency thus used would have three essential range met with in speech and music. parts : its transmitter, the amplifier, These amplifiers, together with the and the loud- speaking telephones. auxiliary apparatus used for supply- The function of the transmitter or ing power to the system and for other "microphone" is to "pick up" the purposes, are usually installed in a voice of the speaker -that is, the room known as the "control room," transmitter creates electrical fluc- although in small installations this tuations when acted on by sound apparatus is often set up at some in- waves. The more closely these fluctua- conspicuous location in the auditorium tions correspond to the sound waves itself. causing them, the less "distortion" the The power output of the amplifiers transmitter is said to produce. The is used to operate the loud- speaking type of transmitter employed for such telephones. In the example we have work is similar in its fundamental chosen, these would be of the horn principle to the ordinary telephone type, consisting of a receiver unit com- transmitter which we use every day, bined with a large straight horn. The

www.americanradiohistory.com One microphone and horn of the public -address installation in the Cathedral of Saint John the Divine, New York horns are mounted in a group approx- in such directions as to cover the mately vertically above the speaker, whole area occupied by the audience. at a height of about twenty-five feet, When the system operates, the aud- tilting downwards slightly from the ience will not, so far as its ears in- horizontal, and pointing out radially inform it, he conscious that any artifi -.

{5),

www.americanradiohistory.com cial means is being used to reinforce coming from a multiplicity of sources. the speaker's voice. The transmission There is a limit to the amount of is of sufficiently high quality for the amplification which can be applied in reproduced sound to appear natural, the case we have described. This arises and the effect of placing the horns in from the fact that part of the sound a cluster above the speaker creates energy from the horns travels back the illusion that all the sound is pro- through the air to the transmitter, ceeding from him. There would be through which it again passes into the danger of losing this illusion if the system. If the amplification is high loud - speaking telephones were scat- enough, this will lead to oscillations tered about the auditorium, as there being set up in the system, and a sus- would tend to be an appreciable time tained singing noise will be heard interval between hearing a sound from the loud- speaking telephones. from the speaker and hearing it from Just before this stage is reached the the different horns. This would pro - output of the system will begin to de- duce an effect like echo, and there teriorate in quality. With most gath- would also be a disagreeable and con- erings sufficient amplification can be fusing impression that the sound was obtained before this limit is reached. In many auditoriums the speaker's voice is heard loudly enough, but there is difficulty in understanding because the words sound indistinct and appear to run into each other. This is generally due to the auditorium being excessively re- verberant, which happens when most of the interior surfaces are of hard materials, such as plaster or stone. The duration of sounds in such an interior is unduly prolonged, because the waves undergo many successive reflections from the various hard surfaces, instead of being quickly absorbed, as they are on striking soft surfaces, such as drapery or carpets. This pro- longation causes each syllable to be confused with the next, and so tends to make speech un- intelligible. A simple public address system of the type just described often overcomes this condition, because if the speak- Control room of a typical -fl public- address er uses a low tone, the reverber- installation ation caused by his own voice {52}

www.americanradiohistory.com Philadelphia celebrates the Sesquicentennial of Aaaerican Independence. The huge stadium is equipped with one of our public -address systems* can be greatly diminished ; and since of there being only one transmitter the horns are directed so as to throw position, several may be provided, in their sound on the audience, where it the same room or in separate rooms, is largely absorbed, the total amount for use on different occasions. Besides of sound which reaches the hard re- coming from a transmitter, the input flecting surfaces of the interior is re- of the system may be taken from a duced enough to make the reverbera- radio receiver, from a telephone line, tion unobjectionable. In many audi- or by means of an electrical repro- toriums, inaudibility due to their large ducer from a phonograph record. size and unintelligibility due to re- Where there are several transmitters verberation have both to be contended or other sources of input, a transmit- with. ter control panel is used to select the What has been said about voice re- proper source on each occasion when inforcement applies equally well to the system is used. This is accom- music produced by a soloist or an or- plished by means of a dial switch hav- chestra. ing several positions, a different The various other applications of source of input being connected at public address systems can be viewed each position. If it is necessary to as developments from the typical lay- REI.I. LABORATORIES RECORD, July, 1926, page out which has been described. Instead 219. 453}

www.americanradiohistory.com pick up sound from several scattered standpoint of public -address system sources at once, as with several per- work, there is a difference between formers taking part in a theatrical horn and cone type loud- speaking tele-

production, or a large orchestra, it phones which is worth noting : namely, may be necessary to employ several that the cone type distributes the transmitters simultaneously. This is sound much more broadly. For this accomplished by means of transmitter reason, we generally use only horns grouping panels which provide means for local reinforcement; if cones were for combining but separately controI- used, so much sound would be carried ling the output of the different trans- back to the transmitter that the oscil- mitters. This is of great value in ob- lating condition previously mentioned taining the proper balance between would set in before sufficient amplifi- different parts of an orchestra or be- cation had been obtained. tween a singer and an orchestra. It sometimes happens that speech Besides reproducing sound at a or music has to be reproduced over point where it originates, for the pur- some area like a park, which is too pose of local reinforcement, a public large to be covered according to our address system can be used to repro- preferred practice by a single group duce sound at as many other points of loud- speaking telephones. Supple- as required. Usually these are in the mentary loud - speaking telephones same building, but if necessary some must then be used, and great care has of the output can be delivered to a to be exercised, when laying out and telephone line for this purpose. For installing the system, to avoid objec- controlling the various output circuits tionable acoustic effects of the kind of the system, a volume -control panel which were previously mentioned as is used. This consists of an auto- trans- likely to occur when a listener hears former with a large number of taps, the same sound coming from two or which are multiplied to dial switches. more sources some distance apart. Each dial switch is connected through Headsets are used with a public a cut -off key to a circuit in which one address system in such places as hos- or more of the sound reproducers are pital wards or hotel rooms, where connected. By this means the proper loud- speaking telephones would be volume level can be obtained in each unsuitable. Headsets operated at circuit. more than normal volume are used to In addition to the horn -type loud - aid members of an audience who are speaking telephones which have been partly deaf. mentioned, head receivers and cone - The use of public -address appa- type loud- speaking telephones are also ratus in electrical phonograph record- utilized with public-address systems. ing was dealt with in the January issue It may he remarked here that the pur- of the RECORD. pose of the larger sizes of cones and One of the most recent develop- horns is not necessarily to produce a ments in connection with public -ad- greater volume of sound, as is often dress systems is remote control. This supposed by the public, but to secure is so arranged that in a school, for better reproduction of the low fre- example, the principal, by means of a quencies which are an important ele- set of keys mounted on a panel in his ment in musical quality. From the office, can start the system, or in case 454}

www.americanradiohistory.com Directing "The Hunchback of Notre Dame" with tau aid of a public- address system of emergency appropriate it from any telephone located in the control other use to which it is being put, and room. The operator can make a then talk through a transmitter on his rough check on quality and volume by desk to any parts of the building which this means and can also follow the he may select. program. Another means is the use :1s already mentioned, in many in- of what is called a volume -indicator stallations the amplifying equipment panel. The volume indicator consists is located in a separate room, which of a sensitive galvanometer operated may be so situated that the operator by means of a rectifying tube from of the equipment has no direct means the output of the system. By adjust- of observing conditions at the points ing the amount of power supplied to where the transmitters and sound re- this galvanometer until it gives a producers are being operated. How- standard deflection, it is possible to ever, three indirect means are avail- measure accurately the power output able, any or all of which may be used of the system. The third means by to enable him to keep in close touch which the operator is enabled to keep with the operation of the system. in touch with conditions is through One of these consists in monitoring the use of an intercommunicating sys- the output of the system by listening tem, in cooperation with one or more to it with a headset or loud- speaking observers who remain at the points

15 5}

www.americanradiohistory.com where the audience is located and re- may sometimes permit more rapid port to the operator whenever it is commercialization of one particular necessary to make changes in the vol- type of system, but it makes it difficult ume or balance, or when it is neces- to use any apparatus interchangeably. sary to switch from one transmitter Our public- address equipment, like to another. Each observer is provided Bell System apparatus in general, is with a handset, while the operator designed according to the second uses a breast transmitter and head re- method, which gives maximum flexi- ceiver. bility and ultimate economy. We have at present three sizes of As might be expected of apparatus public -address equipment. The most offering so many different possibili- powerful is known as the No. i Pub- ties, our public -address systems are lic- Address System, and is intended being used for a remarkable variety for dealing with outdoor gatherings of purposes in a field so wide as to in- and large buildings. The No. 2 sys- clude practically every kind of large tem is intended to deal with small building or place of assembly, and outdoor gatherings and interiors of confidence in the results obtainable moderate size. It is generally similar has begun to reach the stage where to the No. i system, except that a less large projects are under consideration powerful output amplifier is em- whose commercial success will be ployed. The No. 3 system is intended largely dependent on service rendered for use in small installations. It is by equipment of this type. much simpler than the No. i and A considerable amount of engineer- No. 2 systems and does not include ing is required in connection with the various control panels used with work of such diversity, where no two the former. problems are exactly alike and fresh A considerable part of the appa- combinations are constantly occur- ratus used with public address sys- ring. Engineering recommendations tems is also used with radio broad- for proposed installations are pre- casting systems. In this connection it pared on the basis of information ob- is interesting to note that such appa- tained from the prospective pur- ratus may be developed by two en- chaser, or, if the nature of the prob- tirely different methods. One plan is lem demands it, from a physical sur- to so design it that the distortion in- vey on the spot. The recommenda- troduced by one part, for example, a tions include the plan which is to be transmitter, is cancelled by equal and followed in making the installation, opposite distortion in another part, and give sufficient information to en- such as its associated amplifier. The able the customer to complete the other method of development is to necessary wiring. The installation is make each part of the equipment as carried out by the customer, but in nearly as possible perfect and free most cases it is done under our engi- from distortion. The former method neering supervision.

www.americanradiohistory.com In The Month's News

TELEPHONE PIONEERS tO the num- groups of photos showing various ber of more than seven hundred visited stages in permalloy manufacture and our building on August 27, as one of in cable laying. The remainder of the the events of their Thirteenth Annual display showed the sequence followed Meeting. In the Auditorium they in the making of permalloy wire and were formally welcomed by John tape, and also exhibited several sam- Mills, who described the Labora- ples of cables including the first suc- tories, their work for the Bell Sys- cessful transatlantic and the first per - tem and how the fundamental studies malloy cable. had been applied in the phonograph THE AZORES EARTHQUAKE which and motion -picture field. A special occurred on August 3 I st was the cause showing of some of the Vitaphone of considerable inconvenience to two specialties was made under the super- of our engineers, G. A. Locke and A. vision of G. E. Mather and his staff. Melhose, who for several months Many of the Pioneers visited our have been working on the New York- Historical Museum, where they were Azores cable. Practically every build- received by W. L. Richards, W. C. F. ing in the town of Horta on the Island Farnell, A. K. Aster, C. D. Hans- of Fayal, where they were staying, com, Miss Boman and Mrs. Hadfield. was damaged, many were destroyed, The arrangements for the visit were and all water and electric light serv- made by S. P. Grace, who represented ice was interrupted. Both the office the Laboratories on the headquarters and station equipment of Western committee for this convention of Pio- Union suffered slightly. The storage neers and by L. S. O' Roark who is battery plant is now being replaced, responsible for the scheduling and and only a slight delay will be expe- utilization of our new auditorium. rienced. After the disaster the Labo- THE CELEBRATION OF TILE FIFTI- ratories' engineers assisted Western ETH anniversary of the American Union in every way possible to restore Chemical Society held in Philadelphia its service and equipment to normal. from September 6th -i ith was at- These men have now taken up tem- tended by the following men of the porary lodgings in two incompleted Laboratories: R. R. Williams, J. E. houses with fifty members of the Harris, E. E. Schumacher, H. T. Western Union staff until the tents Reeve, C. L. Hippensteel, R. E. Wa- supplied by that company can he set terman, G. T. Kohman, J. A. Lee, up. It might be interesting to know A. R. Kemp and J. T. Acker. In the that Mr. Locke reported that the exposition section of the convention rumors of a bubonic plague in the the Laboratories was represented by Azores are unfounded. a permalloy exhibit. This included a H. E. IvEs attended a meeting of device for showing the magnetic prop- erties of permalloy,* and several * BELL LABORATORIES RECORD, November, i925. 1571'

www.americanradiohistory.com the American Astronomical Society in Trade and Transportation, an or- Nantucket during the week of Sep- ganization devoted to commercial tember 5th, and also visited the and civic welfare. Woods Hole Biological Laboratory. W. V. WOLFE attended the Pacific D. H. NEWMAN has returned Coast Convention of the A. I. E. E. from Port -au- Prince, Haiti, where held in Salt Lake City the early part he was supervising the installation of of September. He later visited San a No. Io6 Radio Telephone Broad- Francisco and Los Angeles to study casting Equipment. the power -line carrier situation on the F. S. BERNHARD iS now located at Pacific coast and spoke on transmis- Santiago, Chile, where he is making sion problems before the electrical a preliminary survey for a point -to- students of California Institute. point radio- telephone system near J. B. KELLY attended a meeting at Santiago, and testing a power -line Colorado Springs of the American carrier- telephone system between San- Academy of Ophthalmology and Oto- tiago and Valparaiso. laryngology. P. H. BETTS has just returned R. M. BURNS, accompanied by H. from Gibson, Indiana, where he su- T. Byck, and Dr. J. J. Johnston, left pervised the installation of a radio at the end of August for Seattle, San system* to permit telephone com- Francisco and Los Angeles to study munication between the yard master in the field the effect of corrosion on and the engineer of switching locomo- cable sheathing. tives in the Gravity Classification W. C. JoNJ s visited the I -Iaw- Freight Yards of the Indiana Har- thorne Works early in September in bor Belt Railway, (a subsidiary of connection with the manufacture of the New York Central Railroad). the No. 555 loud speaking receivers H. W. DIPPEL, of the Purchasing which are being used in the Vitaphone Department, D. W. Mathison of equipment. Apparatus Development, and J. Al- E. L. NORTON of the Research den of the Commercial Department Department, accompanied by H. T. of Western Electric, recently visited Martin of the Apparatus Develop- the Henry L. Scott Company of Prov- ment Department, spent a week at idence in connection with the design the Hawthorne Works in connection and manufacture of a new machine with the production of an electro- for the precision testing of wire insu- magnetic reproducer. lation. This is a recent development T. C. FRY and W. A. SIIEWHART of the Laboratories. were in Columbus, Ohio, during the J. W. McCAw, buyer of chemicals week of September sixth attending in our Purchasing Department, at- the meeting of the American 'Mathe- tended the convention of the Amer- matical Society. ican Chemical Society at Philadel- J. J. GILBERT returned on Septem- phia. ber seventh from a three months' stay J. S. HARTNETT has been named in Newfoundland, where he was do- as representative of the Laboratories ing work on the Bay Roberts -Pen- on the New York Junior Board of zance permalloy cable. D. G. BLATTNER was in Philadel- * The experimental system was described in phia from September first to fourth an article by Mr. Betts on page 79 of the REC- ORD for April, 1926, to introduce a number of improve-

www.americanradiohistory.com ments in the Bell System exhibit of R. L. JONES and S. C. MILLER talking moving- picture equipment at were recently in Boston discussing the Sesqui -Centennial Exposition. He with New England Company engi- also spent two days in Atlantic City neers the quality of supply materials in connection with the introduction of being furnished to that company. the Vitaphone in that city. TIIE PITTSBURGH SECTION, A. I. KARL K. DARROW attended the in- E. E., was addressed on September ternational conference on magnetism 14 by P. B. Findley of the Bureau of held at the Technische Hochschule of Publication. Under the general title, Zurich from June 21 to June 26, and "Landmarks in Communication," he the meeting of the British Associa- described some of the outstanding de- tion for the Advancement of Science velopments of the Laboratories. at Oxford from August 4 to August AMONG CONTRIBUTIONS Of Bell I O. Laboratories men to the literature of H. A. FREDERICK returned on July technical progress may be noted: 15th from Cleveland, where he spent "Complex Magnetism," by Eugene three days attending the tri- monthly Peterson, Physical Review, conference of the American Tele- March, 1926. phone and Telegraph Repair Com- "Some Photographic Problems En- mittee. countered in the Transmission of T. L. DOWEY, whose article on Pictures by Electricity," by Her- public -address systems appears in this bert E. Ives, Journal of the Op- issue of the RECORD, is now engaged tical Society, March, 1926. in sales engineering of such systems "A Radio Field -Strength Measur- with the Graybar Company, to which ing System for Frequencies up to he has been transferred. Forty Megacycles," by H. T. J. P. MAXFIELD visited the Victor Friis and E. Bruce, presented at Talking Machine Company at Cam- a meeting of the Institute of den on August 17 to discuss the pol- Radio Engineers, May, 1926. icies regarding future development "A New Mechanical Test for Rub- work to be undertaken by the Labo- ber Insulation," by C. L. Hip - ratories in connection with the con- pensteel, Industrial and Engi- tract existing between the Victor Com- neering Chemistry, April, 1926. pany and Western Electric. "The Balanced Sea Earth for DURING AUGUST, R. M. Moody, Cables," by J. J. Gilbert, The C. J. Hendrickson, W. A. Boyd and Electrician, August 6, 1926. H. F. Kortheuer were in Hawthorne WILLIAM FONDILLER'S contribu- in connection with regular Survey tions to the development of loading Conference Work. R. H. Hart and have been recognized by the publica- S. C. Miller visited Pittsburgh and tion in the Italian journal, "Tele- Lebanon, Pennsylvania, in connection graphi e Telefoni" and in the Ger- with Survey Conferences with steel man paper, "Physikalische Berichte" manufacturers. In company with of extensive abstracts of some of his W. A. Shewhart, Mr. Miller also vis- recent papers. ited the pole plant of the American J. B. ODELL has resigned as Direc- Forest Products Company, which is tor of Bell Telephone Laboratories, located at Yarmouth, Maine. and is succeeded by E. S. Bloom. 4591

www.americanradiohistory.com Introducing the 1926 College Graduate

By MAURICE B. LONG, Educational Director

DURING the summer a num- the territories of fourteen Bell com- ber of recent graduates of en- panies. From any single institution gineering schools and colleges the largest number is seven, that from have become members of our Labo- Massachusetts Institute; others con- ratories. In an introductory survey, tributing more than two are Har- essentially that described in the REC- vard, Yale, Union, Columbia, New ORD a year ago, they have been told York, Brooklyn Polytechnic and the the organization of our System and University of Iowa. the Laboratories, before starting The assembly of this widely repre- work in particular departments. sentative group, chosen in accordance Like its predecessors, the group with the ideals of the Laboratories, is has been recruited from institutions another illustration of cooperation spread over the entire country and and coordination within the Bell Sys- includes also men with degrees from tem. In advising suitably- qualified foreign universities. Sixty education- men in universities about the work al institutions are represented and and opportunities which our Labora-

Top Row: A. B. Bailey, M. 1. T.; L. E. Krohn, U. of London; H. B. Deal, M. I. T.; H. Lathrop, Vermont; C. F. Iliaylott, Worcester Poly.; J. T. Wilmarth, Colgate; H. W. Bode, Ohio State; W. R. Steeneck, N. Y. U.; J. W. Tate, N. Y. U.; W. E. Campbell, LI iiwaters Rand U.; H. A. Henning, Penn State. Bottom Row: R. G. Watling, Occidental; A. G. Russell, Brown; H. A. Weber, N. Y. U.; II. L. B. Gould, Acadia; S. J. Lambert, U. of Iowa; C. P. Stocker, Ohio U.; T. Slonczewski, Cooper Union; G. II'. Burr, Yale; Y. II'. Prindle, Columbia; E. H. Joyner, P. AI. I. {6o}

www.americanradiohistory.com tories offer, the Operating Companies ing, business, or law. It has looked not only have given great assistance for trained brains, in vigorous bodies, to our Personnel Department but also with pleasing but dynamic personali- have taken an important part in in- ties; for men who will bring sound suring the technical progress of the and fundamental technical training to communication art which is essential their tasks, and give promise of mak- to their own welfare. Theories and ing engineering contributions and of inventions, laboratory investigations developing, as occasion requires, into and designs, of the telephone equip- supervisors of similar tasks. ment of the future will be the task It expects that they will approach and creative opportunity offered to their work with intellectual curiosity, these young men. and with an ability for and a habit of For this important work the Labo- study, which will respond to the facil- ratories has sought, and believes that ities offered by the work itself and by it has found in them, certain char- our "out -of -hour courses." It trusts acteristics. It requires technical that they will learn from the rest of training in the engineering sciences us by association and will cooperate usually, but occasionally in account- with us and thus avail themselves of

'l'op Row: 1I. II. Holland, Columbia; N. II. Thorn, Bucknell; ¡f. Get- tysburg Col.; G. C. Peterson, Iowa State; L. B. Milton, M. I. T.; A. Grendon, Columbia; E. B. Stallman, M. I. T.; I. U. Williams, Penn. State; J. 1:. Nielsen. Roved Tech. Col., Copenhagen, Den.; M. S. Glass, U. of Chicago; D. II'. I:itner, Maryville; F. E. Ninnneke, Brooklyn Poly.; H. O. Wood, J. II. RohrGuuoh. Wooster. Center Row: A. N. holden, Harvard; A. S. Worfolk, Stevens; F. W. Winters, Harvard; J. W. Brown, U. of Wash.; II. A. Lewis, Cornell; F. F. Stoner, Harvard; L. E. Krebs, Carnegie Tech.; C. T. IUood, Union; W. B. Snow, Stanford; C. P. Thomson, Princeton; K. M. Weeks, N. Y. U.; B. E. DeA1ari , .Jr. , IT. of Penn.: E. Swanson, Lund's U., Sweden. Bottom Row: D. E. Trucksess, Penn Slate; F. A. Hinshaw, Kansas State; T. L. Dimond, U. of Iowa; A. E. Kerwien, Union; B. F. R1111 y011, Illinois; A. Riz'enes, Montana State; J. R. Reeves, 17. of Oklahoma; L. A. l.ehaut, U. of Paris; W. A. Ock, Brooklyn Poly.; F. R. Stansel, Union. {6 II

www.americanradiohistory.com opportunities for advancement in our incomplete. They know that on the industry. Their first evidence of abil- average our executive positions are ity to do so will be the quickness with held about fifty -fifty by men of college which they learn and produce: upon training and men whose education has the basis of the trust engendered by been less formally acquired. For their technical production and by their them, as college graduates, oppor- cooperation will depend their opportunities for study and introductory tunities for broader responsibilities. courses are not uniquely provided, They have come to our Labora- but are merely part of the general tories, so far as we know, not "over- scheme, within our organization, sold" on its opportunities; but be- illustrated by out -of -hour courses, to cause they expect to find in it the char- establish facilities to individual acter of work in which they are most growth and advancement fitted to the competent and will be most satisfied. training or experience of its various To them it offers work of engineering members. Their success with us and importance and of social value, under our development of their abilities are conditions which will stimulate the matters which will be individual and greatest team play and assure those are of the future; but the association pleasant human relationships without has been formed on the basis of a which one's professional life would be frank and mutual understanding.

Top Row: T. G. Castner, Drexel Inst.; II. Hon-is-on, Worcester Poll'.; C. B. Sutliff, I1. of Iowa; H. Barnard, Columbia; A. E. Thiessen, Hopkins; W. A. Hyde, Stanford; E. S. Pennell, Bou loin; C. B. Mullett, ;Michigan; C. N. Nebel, Missouri; F. B. Anderson, U. of Penn. Center Row: F. L. Crutchfield, No. Carolina State; A. L. Beach, Pratt; G. W. Wilson, Middlebury; J. G. Mclror, Royal College of Science, Dublin; E. W. Conger, No. Dakota; R. C. Koernig, U. of Colorado; I1. N. l'I' agar, Harvard; H. G. Romig, California; G. Garbacz, Milwaukee College of Engineering; W. W. Perkins, Maine; G. E. Atkins, Roanoke. Bottons Row: D. S. Bender, Rensse- laer; H. R. Kimball, M. I. T.; F. J. Beck, B. P. I.; B. H. Carmen, Rensselaer; F. S. Kinkead, Ohio State; C. E. Germantown, Lafayette; C. O. Wells, U. of Oregon; M. H. A. Lindsay, M. I. T.; N. Bishop, Yale; C. P. Carlson, Michigan. 462}

www.americanradiohistory.com What Is Service?

By J. S. HARTNETT

IN these days of prevailing slo- and human relations, the assisting of gans, we naturally hear much a business within itself and of trade about service -in business, in the in general, inter -relatedly. Do we public prints, on the air. Being thus stray then in saying that service is a lively topic, it is idealized and, con- necessarily a guiding spirit to an troversially, ridiculed. There arc actual end ? those who consider it an essential of The answer to any question is best business and those who would insist found in experience. Within our Lab- that it acts only to cloy. What is it oratories we have established Service, then, this common denominator of all centrally and in our various depart- of our slogans? ments. Does it help us achieve our Basically, if hromidically, behind end? In movie technique, 1 give my every such word is a collective idea. conclusion first. It must and does. It As a word, "service" is a little one is inherently part of everything that grown big. The idea it conveys has we do, from the manufacture of an expanded apace. Time was when the individual audiphone to the eventual word was used principally as an occu- laying of a cable to the shores of the pational classification. It inferred un- :lzores. Service is our sub -structure, skilled labor. The phrase "service tested daily in its solidity. organization," if used at all, would Flash back through the factors con- have had reference to the laundry, tributing to this conclusion. Funda- the dairy, or other agency of the mentally, in the case of the cable, we household. Its implication was more have research in permalloy and cable or less menial. Servility or servitude loading, problems of insulation and were its connotations. Truly a word transmission measuring, apparatus de- of inhibition. velopment of terminal facilities -all Decades pass and values change - studies of infinite detail. These will even in words. The meaning of "ser- require that materials be purchased, vice" is now broadly reversed. We received, tested, manufactured, tested talk of it as the spirit of service. We again as finished products, and finally call our Bell System, assuredly a unit delivered to ships. There will inter- of mobilized skill, a service organiza- vene the preparation of laboratory tion- "one system, universal service." reports, the transmittal of working We find service staffs within almost data, the despatch of telegrams, the every business, and similarly each ad- provision of funds for our engineers vertises its service at large. It thus to travel to Hawthorne and Lisbon. evolves that this word, which in one Figures of estimated costs will he pre- sense came out of the kitchen, is used pared, expenditures accounted for as to symbolize the coordination of man- incurred, and final costs made statis- agement, the promotion of industrial tical as we finish. The whole roster J(63}

www.americanradiohistory.com of our personnel, from the Director dividually, who will be serving the in- of Research and the Apparatus De- terests of all of us. A shipment will velopment Engineer to the decoder need to be made : upstairs the engi- of cablegrams in our Telegraph De- neer will have attended to assembling partment and the instrument maker the apparatus to be shipped; some in our Engineering Shop will in some place in the lower floors of the build- way at some time bend efforts to pro- ing there will follow the preparation duce this newest Atlantic cable. of the necessary shipping instructions, In such a large and diverse organi- the packing and crating of the ma- zation, it may be asked if service can terial to be shipped, the arrange- always be effectively coordinated. ments for its transportation. In all Can it be a pervading spirit? Yes of which is involved from the ad- and yes. ministrative or service standpoint, the Flash back again, in closer detail. entire gamut from the maintenance of In our merchandise service we have the necessary quantity and kinds of entailed, for instance, the matter of shipping forms to the legal execution our material requirements in the op- of a trucking contract- unitized steps eration of the Laboratories. These in unified action. requirements are legion: thumb tacks, We find also in the course of our a motor- generator - what not? If work the occasion for much utiliza- the materials be such as are used with tion of office service. Look into our regularity, we must store them in Transcription Department and see quantities consistent with their con- there what is the nearest approach to sumption. We have thus set up our perpetual human motion among us: merchandise assets and we must con- the concentration of a large staff of trol these assets in such a way that we stenographers, typists, duplicator op- provide the requisite quantities for erators, all constantly at work in normal use and yet keep these quan- turning out correspondence, specifica- tities within bounds so that they are tions, bulletins, instructions and all the represented on our balance sheet as a natural flow of written material that liquid asset rather than one which is must go forth on the sea of business. stagnant or frozen. There must be The dictation of a specification by an here then in the service of keeping engineer will engage at the other end stores the application of broad knowl- of a telephone one of these typists edge of material uses, the study of who remains to him only a voice but trends of consumption and the intelli- whose efforts in the joint completion gent handling of the whole to guard of this piece of work are yet of im- against surplusage -in a phrase, co- portance. From the end of another ordination of effort and cost. telephone, messengers are despatched Similarly the other phases of this to appointed rounds. Down in the merchandise service must operate fantastic glare of our photograph from day to day in active concert. room, someone else, expertly trained, Deep as some of us may be in our will be photographing some device in engineering or research work, we are which the engineer will he interested, all, however engaged, none- the -less having previously on another occa- kindred. There are people of whom we sion even photographed the engineer rarely see and seeing, do not know in- himself. From an adjoining room, 164k

www.americanradiohistory.com blueprints roll out by the hundreds. Our personnel must provide the hu- For correspondence between depart- man elements -the brains and ideas ments, a travelling post office hastens whether technical or administrative, distribution. And when some of us while our systems of service merged have reached dessert at dinner, others therewith and guided thereby provide are clicking away on the printer tele- the material phases. graph our messages to Hawthorne. Such then is the so- termed spirit of So again, in our so- called office ser- service as we carry it out. Granted vice, multiple efforts individually that we may be too indulgent in the exerted will grease the ways. use of this word or phrase, there is Similarly, in every 'department of apparently none better for it. It is service. Our plant must be adequate. something of what the French call Elevators must be run up and down, esprit de corps. Our smartest writers lights lit. Someone must schedule our ridicule it as an evidence of American say- orders for work : in and out of the enthusiasm. They minimize it by Shop, to our customers. A carpenter, ing it is Rotarian, one of the fetiches a physicist need medical attention : a of a go- getting nation. Our smarter nurse, a doctor, are at hand. We seek writers are sometimes over- enthusi- reference to published material; be astic in their self -effulgence. Notwith- it "Who's Who" or a Danish engi- standing these gentlemen, service re- neer's latest conception of repeater mains more necessary than it is evil. operation, library service is available : Within our Laboratories, within any to secure our reading for us, to an- business, between businesses, the fact glicize, to compile. Even recreation is realized, I think, that service is the is serviced. available, assisting element; that From these foci I think it can be those responsible for it must continue seen how "service" fits into our day's to apply to capacity their efforts to work. It is the coordination of util- make it always such. ities and the spirit of aid. It is the A famous man once said that we aspect of our organization which cannot all he deluded all of the time. might be termed one of the two al- A whole people could not misconceive most inseparable elements by which the idea of service. It must he some- our results are produced. Those ele- thing more than the fatuous god of ments are personnel and matériel. the Babbitts. It is. It serves.

www.americanradiohistory.com Club Notes

THE Bell Laboratories Or- strong players to their respective orchestra is about to start its ganizations, many extremely close and 1926 -27 season, the third hot fights are expected in the tourna- since its organization. It invites the ment. The Potter trophy has become attention and cooperation of all mu- the permanent possession of this sicians in the Laboratories. The pur- Club, and we have donated a new pose of this organization is to furnish trophy. This year our old enemies at musical recreation. It is evident to all 195 Broadway have entered a team whose tastes lie along these lines that and we know that beating West Street the enjoyment of each individual in will mean more to them than the an organization of this kind is height- trophy. Broadway is very lucky in ened by the cooperation of every having this year D. G. Grimley and other individual, and for that reason J. M. Stahr, who last season were the every musician in the building should No. 1 men on the West Street and identify himself or herself with the Hawthorne Club chess teams. orchestra and work for its success A Bell System Chess League this season. While the details of is now being discussed, and if a suffi- the season's program have not been cient number of the branches of the worked out it is assured that plenty Bell System are interested, plans will of musical work both in rehearsal and be started as soon as possible for the public appearance will be forthcom- organization of such a league. ing. All interested in chess are cordially The first rehearsal will be held on invited to attend games; Captain Voos Monday, September 21, in the Rest will always welcome new players. Room. Anyone wishing to discuss the activities of the orchestra in more de- BASKETBALL tail is urged to get into touch with any one of the following officers of The Inter - departmental League the organization: Conductor, L. E. League for men will open the 1926- Melhuish; Business Mgr., W. A. 27 season in November with eight Krueger; Librarian, R. J. Podeyn. teams competing for the individual prizes and the Department Trophy. CHESS All league games will be played on Tuesday and Thursday evenings, The knights of the chess board will starting November 2nd, at Labor be seen in action again this month Temple, 14th Street and 2nd Avenue, with the opening of the season. New York City. Two games will be Again this year we have entered played every evening, the first start- a team in the Commercial Chess ing promptly at 5:3o P.M. Club League of New York City, and as members and their friends who may all the teams have added some very be interested are always welcome at -{66k

www.americanradiohistory.com these games. No admission is charged. tee that there is no let -up this year in The departments which will be rep- the enthusiasm. resented in the league are Commer- Applications were received from cial, Research, Equipment, Toll and 133 men desiring to take part as reg- Circuit, Tube Shop, Apparatus De- ulars throughout the season, but the velopment, Patent, Inspection, and Committee was obliged to place 13 Junior Assistants. of these names on the substitute list. In addition to the inter- depart- It is the desire of the officers that mental games plans are now being more men signify their intention of made for the organization of a Bell becoming part time bowlers and serv- Systems Basketball League in which ing as substitutes during the coming will be represented the various season. A careful study of the or- branches of the Bell System located ganization of the Bowling League in and around New York. Any club will show that the substitutes play just member who has not played in the as important a part in the League's club league before this season should activities and success as the regulars. consult at once with D. D. Haggerty. No League could exist without an active substitute list and a hard -work- HANDICAP GOLF TOURNAMENT ing substitute committee. The officers of the Bowling Club Contestants in the Club's Golf Tour- for the 1926 -27 season are: nament assembled at Salisbury for the C. W. Lowe, General Chairman. qualifying round on Saturday, Sep- E. D. Johnson, General Secretary -Treasurer. R. J. Miller, Chairman, Group "A." tember II th. Sixty entries were re- A. R. Thompson, Sec. -Treas., Group "A." ceived, among which were some of W. B. Prince, Chairman, Group "B." G. A. Brown, Sec. -Treas., Group "B." the Club sharpshooters such as W. A. Bollinger, Chairman, Group "C." J. Hiller, G. Kellogg, G. Lewis, E. F. Broome, Secretary -Treasurer, Group "C." H. Clark and J. A. Burwell. Full Bowling is an activity which affords details of the tournament will be pub- both recreation and healthful exer- lished in the November RECORD. cise and it is hoped that many new faces as well as the old ones will be BOWLING seen on the alleys this coming season.

On the evening of September 24, WON] EN'S ACTIVITIES C. W. Lowe, Chairman of the Bowl- ing Committee, gave the signal which Arrangements have been made for opened the season and started 12o the women's swimming class at the men in the Club Tournament, which Carroll Club at 5 :30 Wednesday eve- will consist of 84 games bowled over nings, starting October 6, 1926. Miss a period of 28 weeks. This season the Bolan is taking care of the registra- Club Tournament is being held at tions and can answer any of your Dyer's Manhattan Alleys, located at questions regarding this activity. 168o Broadway, instead of Recrea- There were several other activities tion Alleys located at 368 Fulton proposed in the September RECORD Street, Brooklyn, where our matches which will be announced on the bulle- for the past five years have been held. tin board as the plans are completed. The attendance on the opening night Any one of the women's committee has proven to the Bowling Commit- or the Club secretary will be glad to 1671

www.americanradiohistory.com hear from you if you have sugges- Hotel, 49th Street and Lexington tions about any of the present activi- Avenue, and the Club has secured ties, or any new ones in which you special privileges which are available feel that a fair number of the women to its members. would be interested. The hotel charge for the use of the Although some sports may come, pool is $I.So for either afternoon or and some may go, the bridge en- evening session, but if tickets are pur- thusiasts go on forever. At least they chased through the Club Secretary, did not give up during the summer. Room 164, the price is $1.00. The The regular games, however, did be- pool is open until II P.M. on week gin Monday, September loth, with days and 9 P.M. on Sundays. May Murtaugh again planning the games and generally looking after the RIDING players' enjoyment. The women are playing in the Rest Room from five Riding will be continued at Unity to seven o'clock every Monday, and Riding Academy although the classes since they are planning more equip- at Van Cortlandt Park will be discon- ment they will welcome you if you tinued. Arrangements for lessons, are interested in this favorite indoor either in groups or individually, may sport. There is a tournament ahead he made with the Academy at the rate and plans for mixed games. of two dollars and fifty cents for two hours. Miss Gilmartin will be glad FALL DANCE. to let you have tickets at any time you may wish to join the class. The Fall Dance of the Club will be held in the Grand Ballroom of the HIKING Hotel Pennsylvania on Wednesday evening, November to. The music The weather is going to be real will be furnished by Ben Bernie, and hiking weather now. There is just tables will be provided for those de- enough of the frost in the air to make siring to play bridge. Special features walking a joy. All this being true, are being planned by Chairman glance through this program and you McCormack and will be announced. will find several interesting trips for you to take : Tuesday, October 12, SWINIMING Mianus River; Saturday, October 16, Orange Reservation; Sunday, October One of the finest pools in the Met- 24, Little and High Tor; Saturday, ropolitan District is in the Shelton October 3o, Inwood Reservation.