Page:United States patent 771819.pdf/2

No. 771,819.		Patented October 11, 1904.
United States Patent Office. Lee de Forest, of New York, N. Y. Wireless Signaling Apparatus. Specification forming part of Letters Patent No. 771,819, dated October 11, 1904. Application filed May 28, 1904. Serial No. 210,155. (No model.)

To all whom it may concern:

Be it known that I, Lee de Forest, a citizen of the United States, and a resident of the city, county, and State of New York, have invented 5certain new and useful Improvements in Wireless Signaling Apparatus, of which the following is a specification.

My invention relates to apparatus and devices for localizing or determining the 10direction of a station which is emitting wireless signaling-waves.

The object of my invention is to improve and simplify such devices.

The scope of my invention will be defined in 15the claims.

The drawings show my invention embodied in forms now preferred by me.

Figures 1, 2, and 3 each shows a receiving apparatus embodying my invention.

20I have discovered that if a horizontal conductor be mounted to swing about a vertical axis and a wave-sensitive device be placed in series with said conductor and the earth or other capacity or in series with two parts of 25the same conductor the received signal-waves produce currents in said conductor which vary in strength according as the position of the wires approach or depart from a position of parallelism with the direction of travel of the 30waves. By employing as the wave-sensitive device one in which the intensity of indication varies as the intensity of the current the position of maximum and minimum effect may be determined from which the direction to the 35source of the waves may be told.

In Fig. 1 I have shown a horizontal conductor divided into tow parts A A¹, one being a continuation of the other, and a wave-sensitive member D interposed in series 40between these two parts. This conductor is mounted to swing upon a pivot C, so that it may be swung about a vertical axis. Mechanism of any suitable form for making manifest the the changes produced in said wave-sensitive45 device are provided. As shown, this consists of a local circuit containing battery B and telephone-receiver T. Any other suitable devices may be employed for this purpose.

In Fig. 2, I have shown the pivot C as at one 50end of the horizontal conductor A and the wave-sensitive device D in series between this conductor and the earth or other capacity E.

In Fig. 3 I have shown a device like that of Fig. 2, except that I have made a direct connection between the extremities of the two55 parts A and A¹ of the collecting-conductor, thus forming a closed circuit containing therein the wave-sensitive member D. This return connection A² need not be separated any great distance from the parts A¹ and A², but may,60 if desired, be somewhat separated therefrom. In any event I prefer that the horizontal component be much the greater of the two, as this is what I principally rely upon in arrangement for producing the desired effect.65

It is not necessary that the collecting-conductor be proportioned to the wave length. In fact, considerations of convenience and practical operations will limit their length. I have also found that a great length of 70conductor is not necessary in order to secure satisfactory results sufficient for the practical needs of most cases. As the waves progress along the conductor variations of potential are produced therein, which variations are75 communicated to the wave-sensitive member and produce indications which when varied by swinging the horizontal conductor enable the direction of the transmitting-station to be judged.80

In the operation of the device as herein shown the maximum indication will be obtained when the direction of the collecting-conductor corresponds with the direction of propagation of the signal-waves and the minimum85 indication at ninety degrees from this.

The apparatus shown is only given as illustrative of my invention and not with the idea that other forms of apparatus may not be used in carrying out my invention. I do not 90therefore limit my invention to the apparatus shown but define the scope of my invention by the terms of the claims.

I claim—

1. A localizer of the source of wireless 95signaling-waves comprising a conductor having its principal component extending horizontally and short as compared with one-quarter wave length of the received waves, means for turning said conductor about a vertical pivot,100