US463188A - Telephony - Google Patents

Description

J. W. GIBBONEY.

TELEPHONY.

(No Model.)

Patented Nov. 17,1891.`

FISE! Ill l asA UNMED STATES PATENT OFFICE.

JOIIN lV. GIBBONEY, OF LYNN, MASSACHUSETTS.

TELEPHONY.

SPECIFICATION forming part-of Letters Patent No. 463,188, dated November 17, 1891.

Application filed July 28, 1891. Serial No. 400,917. (No model.)

.To @ZZ whom, it may concern:

Be it known that I, JOHN IV. GIBBONEY, a citizen of the United States, and a resident of Lynn,in the county of Essex and Gommonwealth of Massachusetts, have invented a new and useful Improvement in the Art of Telephony or Electric Communication, which l have described inthe followingspecification and illustrated in the accompanying` drawings.

The object ot' my invention is, primarily, to enable electric waves or und ulations of current to be transmitted to great distances or between points connected by an electric conductor in which there exists so large a selfinduction or so great an impedance to variations in the current-flow that the original waves or undulations of current become ordinarilyso modilied, distorted, or confused that their transmission and recognition at the receiving end ot' the circuit become dit'licult, if not impossible.

My invention is intended to make it possible to convey speech or to telephone over much greater distances than has been common heretofore, and to transmit over circuits having a large self-induction or impedance electriccurrent waves or undulations ot changing1 value in such manner that the record of the waves, though made at a slower rate at the receiving end of th'e circuit, shall more nearly correspond in character to the original sounds and may be used to reproduce them.

Briefly my invention consists in making a suitable record of the sound-waves or phonogram-record, causing such record to produce corresponding electric waves or undulations oi current ata reduced pitch or extended period, transmitting such waves or undulations of current over an electric circuit, and recording such waves at the receiving end of the circuit.

My invention will be understood by reference to the following description and the drawings accompanying the same.

Figure l shows an apparatus for producing a sound-record. Fig. 2 shows the application of this record to the production of electric waves, impulses, or undulations oi' current. Figs. 3, 4, and 5 represent waves of sound and current. Fig. G shows sound reproduction through the agency ot' an electric-Wave record. y Fig. 7 is an illustration of one of the ways of obtaining a record at the receiving end of the circuit.

In Fig. l, D is a diaphragm supported in the usual manner in phonographic apparatus and carrying a stylus S, bearing upon a phonogram-blank P uponv a cylinder' G. It is well known that if sound-waves act upon the diaphragm D it will be set into vibration and a corresponding sound-'record cut into the rotating phonogram-blank P.

In the practice of my invention I take the phonogram-record IJ and substitute for the stylus S a follower S, Fig. 2, which controls a variable-resistance transmitter or its equivalent M in an electric circuit a b from a generator G, this circuit passing likewise around an induction coil I by'preference. It now the cylinder P he rotated at the-same rate as when the record was made, electric waves, impulses, or undulations ot current will pass over the line c d to the further end of the circuit; but if this circuit be of considerable length or have a large amount of self-induction or impedance and the electric waves are rather quick in character, it is well known that their transmission becomes ditlicultand even impossible, because they are smoothed out, obliterated, or distorted in such manner that they cannot be recognized as representing faithfully the original impulse. I obviate this diliculty by rotating' the cylinder O at a reduced rate from the normal or the rate' at which the record was made, whereby the electric impulses or undulations of current, while having a character corresponding to the sound-waves, are prolonged in period or produce an electric Wave which would correspond to a sound-Wave ot reduced pitch. circuit c (Z, and because of their slowness are transmitted with greater fidelity than would be the case were they made to correspond in period with the pitch ot the sound-wave. These waves of current are at the receiving end of the circuit passed through a magnet l5, whose armature operates or controls the movements ot a stylus S', reproducing upon a phonogram-blank I upon a cylinder C a record R, corresponding to the electric waves These waves may be passed over the IOC transmitted over the line c d. If now the stylus S', Fig. 2, be replaced by the follower S2, Fig. 6, and the cylinder C2 revolved at the same rate as when the electric-wave record was put upon it, the sound produced would correspond in pitch to the pitch or period of the electric Waves which produced the record;

but if its speed of rotation be increased to a Y suitable amount, the sounds emitted may be made to coincide in pitch with the original sound used in making the initial record at the sending-station, as will be readily understood. Snpposing, for instance, the wave w, Fig. 3, represents a sound-wave impressed upon the phonogram-blank P. If the cylinder C, Fig. 2, be rotated at one-half its normal speed, the electric wave produced-in the cir-- cuit c d would be represented by the wave w', Fig. 3. The relative speed of rotation irnparted to the cylinder C is always made that which is necessary to avoid the induction and impedance troubles in the line c d, which may be a long cable. Thus in Fig. 4 the ratio may be 102110231 :.15, or even more. I do not wish to be understood as con lining myself to any limit in this respect.

In Fig. 5 L04 illustratesl a complex wave, and w5 shows the Wave of current corresponding thereto, which wave would, however, be extended over a period three or more times as great, retaining, however, a corresponding amplitude. lt is of course evident that the longer the Wave wf is made With respect to the wave w'4, the less it will be modified in transmission over the circuit c d and theL more nearly accurate will be the reproduction from the phonogram P2 when revolved at the proper speed. Such a speed of transmission Will be selected, of course, as will give satisfactory results in any given instance.

It may sometimes be desirable to relay the current at the receiving end of the line, and

the slowness of the period of the Waves renders this an easier matter than ordinarily. Thus in Fig '7 the current between the lines c d passes through a magnet B', operating a variable circuit-controller M', controlling a local circuit gh from a current source G, this current passing about a magnet B2, operating the stylus S2, bearing upon the phonogramblank B2 upon the cylinder C2. The record R2 would correspond in ch aracter to that upon the cylinder P.

My invention will be found useful also in cases where it is desired to transmit intelligence secretly over an electric circuit, because upon communication being established with the line surreptitiouslyinstruments and appliances similar in nature to those herein described would be required to be used before the messages could be understood.

That I claim as my invention isl. The method of telephoning, consisting in making a record ofthe sound-waves, causing suoli record to produce slower electric waves, impulses, or undulations of currentof corresponding shape or character, transmitting such slow electric waves or undulations of ,current overan electric circuit, and recording such waves at the receiving end of the circuit.

2. rlheimprovement in the'art of telephony, consisting in producing a phonographic record of the sound-waves, transmitting electrical waves, impulses, or undulations of current corresponding to such sound-waves in amplitude, but having a reduced rate of vibration or pitch, and recording such waves at the receiving end of the circuit.

3. The herein described improvement in the art of electric communication, consisting in making a suitable record of the waves or vibration s, operating a variable-current transmitter by the agency of this record to produce electric waves of a corresponding character, but slower period or rate of change, transmitting such electric waves over an electric circuit, and operating a recorder responsive to such waves at the .receiving end of the circuit.

4t. The methodlof reproducing sounds at a distance, consisting in irstunaking a phonographic record 'of the sound, then operating an electric circuit-controller through the agency of such record to set up electric waves or undulations of current corresponding in character to the sound-waves, but having a greater period, transmitting such electric waves over a circuit for operating a recorder to produce a record of such waves, and afterward operating a mechanism responsive to the electric-wave record for producing audible sounds.

5. The method of electrical communication, consisting in making a record of sound-waves, operating an electric circuit-controller by the agency of said record to produce slower electric waves or eleci ric waves representing sound-Waves of lower pitch and corresponding in character to said sound-waves, making a record of said electric waves by operating a recorder responsive to such waves, and reproducing the original sound by operating said electric-wave record at a speed greater than that at which such record was made.

Signed at Lynn, Massachusetts, July 24, 1891.

JOHN V. GBBONEY.

Witnesses:

J oHN T. BRoDERicK,

BENJAMIN B. HULL.

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