US1660388A - System of synchronizing signaling apparatus - Google Patents

Description

Feb. 28, 1928.

A. L. MATTE SYSTEM OF SYNCHRONIZING SIGNALING APPARATUS Original Filed Feb. 26, 1925 INVENTOR. fllfliatze Patented Feb. 28 1928.

UNITED STATES PATENT OFFICE.

ANDREW L. MATTE, OE S UMMIT, NEW JERSEY, ASSIGNOR TO AMERICAN TELEIHON'B AND TELEGRAPH COMPANY, A CORPORATION 01' NEW YORK.

SYSTEM OF SYNGHRONIZING SIGNALING APPARATUS.

Original application filed February 26, 1925, Serial No. 11,801. Divided and this application filed Hay l, 1927. Serial No. 193,893.

An object of my invention is to provide a new and improved system of synchronizing apparatus at points between which an electrical transmission is effected. Another object of my invention is to provide for proper synchronous relation of the currents in the various parts of an electric signaling sys tem. Another object is to provide for synchronizing by currents of suitable fre- 19 quency, more particularly to synchronlze relatively low frequency apparatus by trans mission of higher frequency currents. Still another object is to govern the frequency of a vacuum tube oscillator by impressing a current of harmonic frequency thereon.

These and various other objects of my'invention will become apparent on consideration of an embodiment of the invention which I have chosen for illustration and 10 which I now present by way of example in the following specification taken with the accompanying drawing. It will be understood that the invention is defined in the appended claims and that the following dell scription relates more particularly to the example shown in the drawing.

The drawing is a diagram showing two stations East and West with two-way transmission between them.

At station West there is a vacuum tube oscillation generator 0 which delivers current of a certain fundamental frequency to the distorter or harmonic generator H, from which a composite current with the fundamental and harmonics goes to the phase splitter N I refer to these fundamental and harmonics as components.

The phase splitter N comprising "the condenser 14 and resistance 15 splits each of these simple components into two phases 90 apart, impressing the corresponding electromotive forces across the filament and grid of the respective vacuum tubes 16 and 17. Since these tubes draw substantially no current from the input circuits, there will be substantially-no reaction on the phase splitter, and the output currents from the vacuum tubes 16 and 17 will be in the proper 90 relation for the two components of each of the component frequencies, the fundamental and the odd harmonics.

The output currents from the vacuum tubes 16 and 17 go to respective attenuation equalizers E which bring the different frequency components to a desired intensity relation. From there the currents go to respective amplifiers A and are put on the respective conductor pairs 18 and 19 to which hand filters BF are connected in multiple. Each band filter BF passes only one of the harmonic frequencies.

Each harmonic component passed by a respective band filter goes to a resective sending network SN controlled by a rey or equivalent device. The signal wave trains from each sending net SN go through a respective band filter SF and thence in mul tiple to the common conductor pair 20 and to the line W It will be seen that the various carrier currents on the line W differ not only in frequency, being all harmonics of a single fundamental, but that for each frequency there are two components 90 apart in,

phase, one componet put on through the con ductors 18 and the other through the conductors 19. All these component currents are modified to form signals by means of the sending networks SN except that one component in one phase is appropriated for securing synchronism at the station East; the other phase of the same frequency is suppressed. The one component current appropriated for synchronizing is put through the conductor pair 13 to the input of a band filter BF, and its output goes on the line W along with the modulated signaling currents.

At the station East the currents received from the line W go through the conductors 23 to respective band filters RF which pass the respective frequencies. These currents then go through suitable phase adjusters PE to the respective detectors D and D whose output currents control the receiving polar relays R and R The detectors D and D also receive cur rents of the same frequency but a quarter phase apart over the conductors 27 and 28 from a source that will he pointed out presently. One of these locally generated bun rents corresponds in phase with one phase of signal current, and the other locally generated current corresponds in phase with the other phase of signal current, and therefore, one phase of signal current is detected I relation are required These are supplied over the respective circuits27 and 28, and" priated for synchronizing and'sent through in one detector D and the other in'detector D,,. For these detectors D and D local currents of the same frequency as the'respective carrier currents and in proper phase their generation inthe proper phase relation will now be'described.

v The particular harmonic frequency approthe conductors 43 at station West may thought of ashaving the frequency nd where d is the fundamental frequency and n is an integral multiplier. At the receiving stal5 tion this particular harmonic will be passed f application of the harmonic frequency nd to.

through an appropriate band filter BF and over the conductors labelled ml to the input ofthe vacuum tube oscillator 46. The natural frequency of. this oscillator 46 is, as

nearly as practicable, adjusted. to be equal to (Z, Whereas the input frequency is ad. The

' the input of this oscillator adjusted rather alrea closely to the natural-frequency d, forces frequency (1.

The output from the oscillator 46 goes through the transformer 47 to the harmonic generator or distorter H. The output-from the said oscillator to operate at precisely the the harmonic generator H- goes to the appa-.

responds to that indicated as Y, and already described in detail.

This application is a division of my application Serial No. 11,801, filed February 26, 1925, and renewed at or shortly before the time of filing the present application.

I claim:

1. The method of synchronizing a relatively low frequency vacuum tube oscillator at a distance by transmitting and applying thereto a current of harmonic frequency,

2. The method of synchronizing two vacuum.tube-oscillators of approximately the same relatively low natural frequency, which consists in derivinga harmonic'current from one of said oscillators and transmitting it and applying it "to the other of said oscillators. a

3. In a communication system, comprising a relatively low frequency vacuum tube oscillator at the sending end and a similar oscillator of approximately the same natural frequency at the receiving end, the method of synchronizing them which consists in transmitting a current of harmonic frequency and applying it to the oscillator at the receiving end and thereby forcing it into synchronism at the said relatively low frequency. a

4. In a system comprising two widely separated vacuum tube oscillators naturally tuned nearly together, the method of forcing one of them to the frequency of the other which consists in transmitting from sai other oscillator a current of harmonic frequency and applying it to the said" one oscillator.

In testimony whereof, I have signed my name to this specification this 19th day of May 1927. a 4

ANDREW L. MATTE."

Images