United States Patent Office.
Guglielmo Marconi, of London, England, Assignor to the Wireless Telegraph and Signal Company, Limited, of same place.
Apparatus Employed in Wireless Telegraphy.
Specification forming part of Letters Patent, No. 647,007, dated April 03, 1900.
Application filed June 13, 1899. Serial No. 720,355. (No model.)
To all whom it may concern:
Be it known that I, Guglielmo Marconi, electrician, a subject of the King of Italy, residing at 23 Mark Lane, in the city of London, 5England, have invented certain new and useful Apparatus Employed in Wireless Telegraphy, of which the following is a specification.
This invention relates to improvements in the apparatus described in the specification 10of Patent No. 627,650, granted to me in June 27, 1899. In that specification I described connecting the aerial conductor to a capacity of an induction-coil, the ends of the 15imperfect contact or sensitive tube being connected to the ends of the secondary. In place of winding both the primary and secondary in single layers, as claimed in that specification, the coils are now either made very short (not 20much exceeding two centimeters in length) or else are wound in sections. The number of turns in the successive layers of the secondary (and sometimes of the primary also) should diminish as the distance from the center25 increases; but this, although preferable is not essential. It is also found desirable to connect direct to the sensitive tube or imperfect contact (not through the condenser) the end of the secondary which is farthest away f30rom the nucleus or axial line of the coil.
Figure 1 is a diagram of the arrangement described in the former specification modified in accordance with the present invention, and Figs. 2 to 6 show modified forms of the induction-coil.35
In Fig. 1, a is the aerial conductor; b, a local battery; c, a condenser; e, a connection to earth or other suitable capacity; j, a sensitive tube or imperfect contact. k are choking-coils, and r a relay working a signaling or40 other instrument. The diagrams of the coils are greatly-enlarged half-longitudinal sections, but are not strictly to scale. In place also of showing the section of each coils or layer of the wire as a longitudinal row of dots or45 small circles, as it would actually appear, it is for simplicity shown as a single continuous longitudinal straight line. A is the end of the primary, which is connected to50 the aerial conductor a, and E is the end connected to earth or a capacity. J is the end of the secondary, which is directly connected to the sensitive tube or imperfect contact j, and C is the end which is connected to it through the condenser. G is a glass tube55 on which the coils are wound. The wires are preferable insulated by a single covering of silk.
The following table give particulars of coils which have been successfully used:
| Figure in drawings. |
Diameter of tube G, in centimeters. |
Diameter of wires, in cen- timeters. |
Resistance in ohms. |
Number of turns in windings. | Length in centimeters. | |||||||||||||||||||||||||||||||||||||||
| Pri- mary. |
Second- ary. |
Pri- mary. |
Second- ary. |
Primary. | Secondary. | |||||||||||||||||||||||||||||||||||||||
| Fig. 1 | .935 | .01 | .01 | . . . . . | . . . . . | 2 layers of 100 turns each, in parallel. | 3 sections of 10, 12, 10 layers with
turns. |
2.5 | ||||||||||||||||||||||||||||||||||||
| Fig 2. | .937 | .012 | .012 | . . . . . | . . . . . | . . . . .do . . . . . . . . . . . . . . . | 4 sections of 9 layers each, with
turns. |
4.0 | ||||||||||||||||||||||||||||||||||||
