shifting to less desirable and therefore less crowded frequencies to avoid interferences, were factors mitigating against its general adoption.

The wire carrier telephone system of the Union Switch & Signal Co. consisted of a transmitter and a receiver at each end of the train, using a side band transmission between 7400 and 9300 cycles. The transmission was largely restricted to track rails with some wayside longitudinal wire used in a few locations. After numerous initial stationary ground tests, 91 train trips were made between July 12, 1933, and August 27, 1937. The final result was that further development work was necessary before general adoption and the project was abandoned to be revised with improvements in June 1942 by extensive trials on the Belvidere branch of the New York division, which are described later in this answer.

The wire carrier telephone system of the General Electric Co. consisted of a transmitter and a receiver at each end of the train using a side band transmission between 6500 and 7000 cycles. The transmission was effected by means of a network of the "ladder" form in which the track and a wayside wire formed the "ladder" rails and the "ladder" rounds were formed by capacity coupled equally spaced cross connections between wire and track. The transmission was largely confined to this network, the energizing of the network traveling with the train. After extensive stationary ground tests, 16 train trips were made between October 1935 and December 9, 1936. In the same period experimental installation of sending and receiving appliances in a wayside signal tower was tried out in connection with the train tests. The final result was that further development work was required before the system would be suitable for general adoption.

In June (5-25) 1936, an experimental installation of two-way radio on five tugboats operating in the New York Harbor was made jointly with the New York Telephone Co. for demonstration purposes. These equipments were used in conjunction with the service offered between ships and shore by the New York Telephone Co. Licenses expired August 20, 1936, at which time the project was abandoned as the railroad was not convinced of the economic advantages. This trial covered a period of 218 tug-days.

At Columbus, Ohio, in November 1940, the railroad placed in service a Union Switch & Signal Co. carrier, wayside wire, hump yard, one-way telephone equipment to operate between the office and three yard locomotives. Its operations has been satisfactory and has demonstrated its usefulness. Other similar installations have since been made at Altoona, Pa., Pitcairn, Pa., Enola, Pa., and Hawthorne Yard, Ind. A two-way communication system between two yard engine equipments and wayside yard offices is being installed at Pittsburgh, Pa. In July of 1941, and thereafter, two-way voice radio was installed on 24 tugboats for use in dispatching service as furnished by the New York Telephone Co. in New York Harbor and adjacent waters. The first set was installed on September 5, 1941, followed by installation on a total of 24 tugboats. The results obtained have been most advantageous.

In June 1942 the railroad placed in experimental service on the Belvidere branch, a two-way voice carrier wayside wire installation, built by the Union Switch & Signal Co., consisting of 1 office and 1 each locomotive and cabin car equipment. A total of 10 locomotives and 10 cabin cars have been equipped with the train telephone and 1 additional office is also being equipped. The present results indicate numerous advantages and further experimentation on other parts of the railroad is under consideration.

Question 5: The Pennsylvania Railroad has attempted to apply and use radio for communication in service where it was most applicable for over 20 years. Actual commercial application of radio has in no case been the simple matter popularly assumed. If there appears to be delay in the application of technology in this field, it can be readily seen it is not due to failure on the part of the railroad to assess the value of radio, nor a lack of desire to secure its benefits. If the lower frequencies now completely assigned to commercial use were available, and if there were no restrictions upon the height of the broadcasting antenna, nor upon the electrical power required, railroads would undoubtedly be using radio telephone quite satisfactorily today. These lower frequencies, however, are not available, and even the high frequencies have become so crowded that there is every reason to expect railroad services will be limited to frequencies above the 200 megacycles limit. There is no doubt that ultimately equipment can be devised for frequencies in this band, but at present there is no commercially produced equipment that would satisfactorily utilize these frequencies and be suitable for railroad purposes.

8-4949-44-pt. 15—14

EXHIBIT No. 394

MAX THEO. WINTSCH, LANCASTER, PA., REPRESENTING THE WINTSCH AUTOMATIC TRAIN CONTROL AND CAB SIGNAL DEVICES

Re: Subject automatic cab signal and train control.

Hon. SENATOR KILGORE,

Washington, D. C.

MARCH 6, 1944.

DEAR SENATOR KILGORE: The writer heard over the radio on Mr. Drew Pearson's broadcast that you are preparing a bill to be presented to Congress about the use of safety devices on our railroads. We do not know exactly just what kind of safety devices you have in mind; automatic roadway signals or automatic cabsignal systems with automatic train control; however, we do know that the use of such devices on our railroads would prevent a large percentage of accidents such as have unfortunately occurred more frequently than ever the past several months, with considerable loss of lives and destruction of railroad equipment with a resultant monetary loss of close to a million of dollars. Under the stress of war conditions it is most likely that many more such accidents may well occur within the coming months.

We have read in the newspapers that one of the railroad companies had installed radio telephone devices on some of their trains so communications could be carried on with the locomotive operators on moving trains. Said devices may ́prevent some train accidents, but they do not strike at the root of cause of such accidents. In most cases of train wrecks it is the human failure to act in time of unexpected danger; train-operating personnel disobey rules; the locomotive operator may not be able to see roadway signals displaying danger conditions on account of fog or smoke, or he may, for other reasons, be unable to respond to such warnings; only an automatic device which does not go to sleep and which is ready to act instantly in time of danger should be used.

The writer and his partner own patents covering automatic cab-signal and train-control devices, which devices have been tested on a railroad under actual operating conditions; these tests were witnessed by representatives of the Bureau of Safety of the Interstate Commerce Commission and the automatic train control committee of the Association of American Railroads. The safety devices as designed by the writer could be installed on our railroads at a cost of onethird or one-half lower than similar devices of competitive companies.

You may not be fully acquainted with the operation of such automatic cabsignal and train-control devices, and I am going to give you herewith a few pointers to explain to you a few operating principles of the cab-signal system as developed by myself.

The Wintsch system, through the visible and audible cab-signal apparatus placed within easy view of the locomotive operator at all times

1. Warns the operator of any adverse traffic condition in the block in which he is in, and of two blocks in advance, regardless of his position in a block. These blocks are sections of track which may be from 1 mile long to 6 miles long.

2. It immediately warns the operator of a broken rail, open drawbridge, or open switch; of another vehicle in the block, locomotive or car, and of an open or shorted track-control current.

3. It informs the locomotive operator of any change to a more favorable or more dangerous traffic condition two blocks in advance. Failure of any of the major parts of the system will automatically stop the train or vehicle. Means are provided for the operator, if he is fully alert, to annul automatic application of the train brakes.

4. It permits high-speed operation of trains through fog and smoke. However, the automatic cab-signal system does not take away the control of the train from the operator; the cab-signal aspects first warn the operator of the danger ahead and he has a few seconds time to apply the brakes in the usual manner; but, if he does not act during that time, the system will stop the train automatically. The basic operating principle of my cab-signal system is the control of a train or vehicle by continuously flowing or interruptedly flowing weak electric currents through the track rails, or the absence of such control currents.

The Wintsch automatic cab-signal system meets all of the requirements for such devices as set up by the engineers of the Bureau of Safety of the Interstate Commerce Commission. You may obtain information as to the tests made of the Wintsch system on the Philadelphia & Western Railway in Philadelphia from the signal and electrical engineer, Mr. William D. Gable, of the said railway in Philadelphia; from the secretary of the automatic train control committee, of

the Association of American Railroads, in the Transportation Building in Washington, D. C.; or of the assistant director, Mr. S. M. Mills, of the Bureau of Safety of the Interstate Commerce Commission, in the Interstate Commerce Commission Building in Washington, D. C. The writer will also be very glad to answer any questions you may wish to ask in reference to my system of cab signaling or other facts referring to similar devices promoted by our competitor.

My partner, Newton M. Weaver, and myself would appreciate it very much to gain your interest in the subject matter and we would welcome your comments and suggestions.

Under the stress of war higher speed of railway trains and utmost necessity of fullest use of track capacities are placing more and more dependence on the constant alertness of the locomotive operators; with this human factor in question we may expect the occurrence of other serious train accidents; then, why not enforce the installation on our railroads of a safe and efficient automatic cab-signal and train-control, such as ours, which can be installed on any type of railroad at a reasonable price?

Yours respectfully,

MAX THEO. WINTSCH.

EXHIBIT No. 395

NEW YORK, March 6, 1944.

Hon. HARLEY M. KILGORE,

United States Senate, Washington, D. C.

DEAR SENATOR KILGORE: Publicized accounts of your interest in end-to-end communication on moving railroad trains prompts this writer to send you (enclosure) copy of a communication, dated January 15, 1944, addressed to the American Association of Railroads.

I believe it will afford an opportunity to visualize and evaluate a system of communication on freight and passenger trains, from the engineer in his cab to the conductor in the caboose, that would constitute a practical contribution toward public safety and public welfare.

Copies of the communication to the American Association of Railroads were sent to key railroad men in the telegraph and telephone sections of every railroad company, and a very great deal of interest has been manifested.

Railroad smash-ups flare briefly in headlines and news reels, and only the wost ones get national attention in these days of roaring war news. Train accidents increased 32 percent in the period for the first half of 1943 over the same period in 1942; total, 8,209 accidents traceable to equipment break-down were up 39 percent, and to improper maintenance 47 percent. In all types of railway accidents, 2.349 persons were killed, though only 41 of these were passengers on trains, and 28,857 were injured, though again only 2,429 of these were train passengers. Although the system of communication I recommend is a "wired" system, nevertheless it would establish the beginning of end-to-end communication on moving trains, enabling instructions to be given to strategic men, thus preventing such impairment of railroad equipment as testing air brakes, signals from one end of car to another, hot boxes, et cetera.

If I may be of assistance to you and your committee with furnishing any specific information, do not hesitate to command me. It is both a privilege and a pleasure to be of service in a worth-while undertaking.

Very sincerely yours,

EXECUTONE Co.,
MYRON A. KESSNER.

Mr. W. A. FAIRBANKS,

JANUARY 15, 1944.

Secretary, Association of American Railroads, Operations and Maintenance Department, Telegraph and Telephone Section, New York, N. Y. DEAR MR. FAIRBANKS: In connection with the country's railroads examination of public safety possibilities in the proposed use of end-to-end communication on moving trains, this writer wishes to submit to the raido technical planning board,

through the Association of American Railroads, a certain precision-built device that is designed and engineered for such application as now is being considered. It can be used for one-way paging or for two-way conversation from front to rear-end communication on passenger and freight cars.

The Executone communication systems cover a wide range of industrial use and today are in operation by almost 100,000 private industries throughout the Nation. It is recognized as one of the foremost communication equipment in terms of economy, efficiency, and dependability. The electronic science of electrical sound transmission circuits has been developed by our engineers to serve communication in its most modern form, and it is particularly adaptable in railroad use, insofar as its service contributes toward the saving of countless steps, valuable time, and money.

It consists of a combination microphone-loudspeaker and electronic or vacuum-tube amplifier. The microphone-loudspeaker, when acting as a microphone, has the property of converting audible sound into electrical impulses. When acting as a loudspeaker, it has the reverse characteristic—that is, converts electrical impulses to audible sound.

When the central control station, commonly known as the master station (in the locomotive engineer's compartment) is operated by the flick of the finger, the sound of his voice is converted to electrical impulses. These electrical impulses are vastly amplified while passing through the amplifier circuits and are then transmitted over a two- or three-conductor shielded wiring line to all cars or any selected car. That car is which a substation is located instantly is contacted, either by remote control which means that the person called can receive the message and make prompt reply without approaching the instrument although at a distance or in absolute privacy, if need be. The substation contains a combination microphone-loudspeaker which is exactly the same as the one in the master station and matched to its characteristics. The electrical impulses transmitted by the master station are now converted back into audible sound and the engineer's voice is heard with the same clarity and naturalness as spoken at the master station.

When the talk-key on the master station is released, the master station becomes a loud speaker and the substation is now a microphone. The reply of the substation is converted to electrical impulses, travels along the wiring line, which is connected to each car by individual pig tails, to the input side of the amplifier of the master station. There the inaudible impulses become greatly amplified and then converted by the loudspeaker to audible sound. Thus, by depressing and releasing the talk-key on the master station, the engineer can carry on a perfect two-way conversation between master and substation or substations, jointly, can be called simultaneously. A great deal of time would be saved in giving instructions and in replies made, whether the call originates at the master station or at the substation.

By attaching a selector to the master station, it is possible to route conversational facilities, as described above, to any one of the several stations selectively, or to page all connected stations at the same time.

You will observe that the sound transmitted by the master station is first amplified and then the high level impulses go out to the substation. The substation can reproduce only these amplified impulses. When not conversing or originating a call, an Executone substation is absolutely silent. The master station can be provided with an Executone annunciator selector, which registers an illuminated signal from any substation and remains illuminated until answered. In addition, if desired, a tone signal can be incorporated, which can be transmitted selectively to any or all substations. This serves as alarm or method of call origination to substations by signal instead of voice.

The speakers can be provided in cone-type mechanism or in diaphragm-type mechanism. Whether the communication system is used as a two-way conversation service or a one-way paging system, Executone equipment is recognized for its quality of tone, balance, and volume. As demonstrated in certain industrial war plants where there exist very high noise levels, and on battleships, et cetra, engaged is combat duty, the significance and importance of Executone equipment is evidenced by its abilities to stand up under a terrific strain.

The establishing of end-to-end communication from the locomotive engineer to the caboose on freight trains, or from the locomotive engineer to the rear end of a passenger train, to be used in emergencies when all other means of communication have failed, would add considerably to the safety factors both for the working crew or the traveling public.

Executone service would be particularly applicable in dense fogs along the river at certain periods of the year, when it is impossible to see signals being given by trainmen. This is also true in heavy snowstorms. It would be adaptable in the application of service to harbor craft operations. It would be a saving of appreciable road time on trains, such as stops caused by a signal, hot journals, or defective equipment discovered by trainmen.

Executone would inform everyone of the cause of the delay, and what is going on, thereby obtaining the utmost cooperation and efficiency. It would enable a message to be received and the trouble corrected before a man could walk the length of the train. It would notify the engine crew when the flagmen are called in and arrive at the caboose. On crossings, the wiring can be disconnected, and then reconnected when the train is moving again. It would save time intesting air brakes, time lost by the brakemen walking to and fro giving signals. When stuck brakes are noticed, the enginemen could be notified through Executone equipment to reduce the speed of the train, permitting the front brakemen to get off and correct the trouble, and then the train proceeds.

Using our standard models, unless special designs or engineering are desired, the cost of an Executone system is astonishingly low. A standard master station with a 10-pushbutton standard selector, equipped for paging or individual selection, is $54. Substations (remote control or privacy type) are $14.50 each. On an average 10-car train, using this as an example, the cost of the equipment would be $199.

Executone systems also are fittingly adaptable, either as a two-way conversation service or as a voice-paging service in railroad switching yards and in railroad terminals. In railroad switching yards, it would enable the yardmaster from his tower to communicate and direct personnel in the yards, and the operation of incoming or outgoing trains. Special lead-covered wiring can be used, which is buried in the ground and connects each integral substation. The yardmaster can stay in his tower, in his office, where he is always available on the telephone, and efficiently direct the work of the yard, thus saving steps and time. It would reduce idle switch-engine time to practically zero, because when a crew has finished one job they can immediately call the yardmaster and get instructions what to do next. If the yardmaster looks out over the yard and sees an engine idle he can call them and ask them what they are waiting for. The various Executone units can be so conveniently located to where the work is being done that he can converse with the switch engine foreman without switching operations being stopped. The safety factor is so important an item that it alone would justify the use of this system, as has already been proven in several yards where two-way communications now are installed.

It is now possible for in-bound trains to get instructions without the hazard of a member of the crew alighting from the engine and going to the yard office. When a track is being coupled, it is possible for the yardmaster to warn men working at the other end of the track.

An Executone paging system could be used as a supplement to the two-way conversation system, in that the yardmaster may call a certain crew over a paging speaker, which may be heard over a rather large area, and tell them to call in over the nearest telephone unit. With full-range amplification, Executone speakers have power and can be heard great distances, even above switch-engine noise. The size of the yard or area to be covered with the amplified sound, and the noise level encountered would require special study by our engineers. All outside speakers are made entirely of metal, with diaphragms that make them not only weatherproof, but highly efficient in high-fidelity speech frequencies. In a room where the microphone is located with a relatively high noise level, a filter can be incorporated or provided for the microphone circuit to attenuate the frequencies. Such a filter also allows the amplifier and speakers to be operated at approximately double the power, without distortion. The microphone itself is of rugged construction and of a moving coil or dynamic type, which is unaffected by normal temperature and humidity changes.

At railroad terminals, an Executone voice-paging system can be used both for straight one-way paging or announcements, and for the broadcasting of planned, selected musical programs, operated by an automatic phonograph record-changer. Music is broadcast through an Executone rack and panel equipment and can be transmitted at designated periods throughout the day. If an important announcement must be made during the music broadcast, the central control operator controls an Executone switch which can cut out the music at designated stations until the announcement has been made, and then automatically resume the music broad