Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS726413 A
Publication typeGrant
Publication dateApr 28, 1903
Filing dateNov 1, 1901
Priority dateNov 1, 1901
Publication numberUS 726413 A, US 726413A, US-A-726413, US726413 A, US726413A
InventorsEugene Ducretet
Original AssigneeEugene Ducretet
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Transmitting and receiving for hertzian waves.
US 726413 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

No. 726,413. PATENTED APR. 28, 1903.




. M m $5M! m: Norms Puma co, PHOTO-LITHO.. wasnmm'o'v u.





SPECIFICATION forming part of Letters Patent No. 726,413, dated April 28, 1903.

Application filed November 1, 1901. Serial No. 80,723. (No model.)

To (tZZ whom, it may concern:

Be it known that I, EUGENE Duonnrn'r, a citizen of the French Republic, and a resident of Paris, France, have invented certain new and useful Improvements in Transmitting and Receiving Apparatus for I-Iertzian -Waves, of which the following is a specification.

In my various notes upon currents of great variations and high tension of Tesla, Thomson, and Oudin I have shown after practical experiments that it was possible to use these currents for the transmission of Hertzian Waves through space, that they increased the carrying power, that applied to aerial radiators and collectors (antennae) some of these devices permitted the regulation or bringing into agreement of the posts with one another, and that it Was very necessary, as shown by Thomson and Tesla in their notes, that the condensers of the discharge-circuit, the capacities, and self-induction circuits of the apparatus should be perfectly regulated with one another in order to obtain the greatest effect.

The device invented by me herein illustrated is of variable shapes and size and is applicable to the devices of Thomson and of Tesla. It constitutes an important improvement, the exclusive property of which will hereinafter be claimed.

In the accompanying drawings, Figure 1 shows an apparatus applied to a Thomson or Tesla apparatus. Fig. 2 shows this apparatus applied to a relay-receiver.

The essence of my invention lies in a transformer for induction-currents and especially adapted for use in connection with transmitting and receiving devices for Hertzian waves, wherein it has been found necessary to exactly regulate the discharge and induction circuits in relation to one another.

My transformer is adapted to enable the relations of the discharge-circuits and the inducing-circuit to be changed at will and as the needs demand. This device consists, essentially, of a solenoid, the number of whose efiective coils may be varied to give different effects upon the introduction of a current thereto and so regulate the discharge with relation to the inductive effects. The means for accomplishing this will be more fully described. Mounted uponthe solenoid S are graduated insulated supports 1 2 3 4:. These supports carry sliding contact-pieces R, R, R, and R, which may be placed in any position with relation to the coils of the solenoid that may be desired. In this manner the number of spirals of the solenoid acted upon by the inducing current, and hence the inductive effects, maybe varied at will. The solenoid may be thus regulated as to either self-inductionor as to inducing action, or the length between a a may be varied for these purposes by the addition of conductors or bridges and suppressing at will the effect of any number of the spirals of the solenoid S. As may be desired these ends a, a may be either connected to suitable sliding contacts of these currents or may be left free.

This apparatus permits numberless combinations which can be realized with three sliding contacts; but the four, Figs. 1, 2, give more elasticity to the adjustments. wound wire S (solenoid) for large sections may be made of several wires, as in the solenoid of La Rives condenser. The insulated supports 1 2 3 4 are graduated. They bring thecurrent to their respective sliding contacts.

This apparatus is reversible by means of suitable spring sliding contacts R. The number of spirals comprised at :r can be smaller or greater than these comprised at 2/ and vice versa. A self induction compensator by anadjustable condenser (liquid ones serve in all cases) may be added at a: and y, according to the uses to which this apparatus is applied.

Fig. 1 shows, by way of example, this apparatus applied to one of Thomsons or of Teslas devices, with a condenser 0, giving an oscillating discharge at O. The tensioncurrent is brought in at i if. The condenser 0, with any number of jars, is of my invention, the capacity thereof being regulated according to the desired effect. For wireless telegraphy the collector (antenna) is at O and the connection to earth at 0.

Fig. 2 shows this apparatus applied to a relay-receiver with radioconductor B It is also applicable to the Popoff-Ducretet radio- Thetelephonic receiver without relay. In this application the wire of the solenoid S is much finer than that in Fig. 1.

In both cases, Figs. 1 and 2, C represents the collector (antenna) either simple, multiple, or tubular. Its adjusting means are not shown. It is likewise with the connection to earth C Figs. 1 and 2. It can be made with or without a suitable capacity condenser.

Having fully described my invention, what I claim, and desire to secure by Letters Patent, is-

A device of the character described, comprising a solenoid for regulating the relation

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5650726 *Sep 22, 1995Jul 22, 1997Oyo CorporationEmitter for an electromagnetic tomography measurement system which connects a greater number of windings to a magnetic core at low frequencies than at high frequencies
US5859533 *May 14, 1997Jan 12, 1999Oyo CorporationProcess for the production of a supply current of a solenoid for a measuring probe for electromagnetic tomography
Cooperative ClassificationH01F21/005