ameter wound over or under the primary winding. The resistance of the secondary winding is about one hundred and forty ohms.
The condenser k1, which I preferably use, 100is composed of six tin-foil or copper plates connected to each terminal, each plate being five centimeters by three centimeters, the plates being insulated by paraffined paper .017 centimeter thick.
105When using the above-described induction coil or transformer, I employ as insulated conductor at each station a conductor formed of seven strands of about one-millimeter-diameter copper wire one hundred and forty feet 110long, the top of the conductor being one hundred and twenty feet from the ground. In some cases I use in lieu of the above-described conductor a galvanized-iron netting about two feet broad and one hundred and thirty 115feet long, the top of the netting being about one hundred and ten feet above the ground. In the latter case I obtain good results when using an induction-coil or transformer constituted as follows: secondary winding of 120three hundred and seventy-five turns of copper wire .005 centimeter in diameter insulated with one covering of silk, and wound on a glass tube .777 centimeter in diameter. Over this is wound the primary winding of 125one hundred and seventy-five turns of a similar wire .012 centimeter in diameter. The resistance of the primary winding is about 7.1 ohms and that of the secondary about 79 ohms.
130What I claim is—
1. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, a capacity, a conductor connected 135to one end of the primary of the coil, a connection between the other end and the capacity, connections between the ends of the imperfect contact and the ends of the secondary of the coil and a condenser in one of 140the latter connections.
2. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, a local battery and relay included in the local circuit, 145choking-coils respectively included in said circuit between the terminals of the imperfect electrical contact and the battery and relay, an induction-coil, a capacity, a conductor connected to one end of the primary of the 150coil, a connection between the other end and the capacity, connections between the ends of the imperfect contact and the ends of the other end and the capacity and connections between the ends of the imperfect contact and the ends of the secondary of the coil.
1553. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, the primary and secondary of which consist of a single layer only, a capacity, a 160conductor connected to one end of the primary of the coil, a connection between the other end and the capacity and connections between the ends of the imperfect contact and the ends of the secondary of the coil.
4. In a receiver for electrical oscillations,165 the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, the primary and secondary of which consist of a single layer only, a capacity, a conductor connected to one end of the 170primary of the coil, a connection between the other end and the capacity and connections between the ends of the imperfect contact, the ends of the secondary of the coil and a condenser in one of the latter connections.175
5. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, the primary and secondary of which consist of a single layer only, and in which180 the primary consists of a number of parallel wires connected at their ends, a capacity, a conductor connected to one end of the primary of the coil, a connection between the other end and the capacity and connections185 between the ends of the imperfect contact and the ends of the secondary of the coil.
6. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an 190induction-coil, the primary and secondary of which consist of a single layer only, and in which the primary consists of a number of parallel wires connected at their ends, a capacity, a conductor connected to one end of the 195primary of the coil, a connection between the other end and the capacity and connections between the ends of the imperfect contact, the ends of the secondary of the coil and a condenser in one of the latter connections.200
7. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, the primary and secondary of which are both of wire not exceeding one-fiftieth of210 a centimeter in diameter, a capacity, a conductor connected to one end of the primary of the coil, a connection between the other end and the capacity and connections between the ends of the imperfect contact and the ends of the secondary of the coil.
8. In a receiver for electrical oscillations, the combination of an imperfect electrical contact, a local circuit through it, an induction-coil, the primary and secondary of which215 are both of wire not exceeding one-fiftieth of a centimeter in diameter, a capacity, a conductor connected to one end of the primary secondary of the coil, a connection between the other end and the capacity and connections 220between the ends of the imperfect contact, the ends of the secondary of the coil and a condenser in one of the latter connections.
Guglielmo Marconi.
- Witnesses:
- Robert B. Ransford,
- John H. Whitehead.
