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Roberto Landell de Moura (1861-1928) - Brasil
Patent n. 771.917 - 11/10/1904 - United States Of America Government - obtained from

Prototype of the "Wave Transmitter" built by The Science and Technology Foundation
of Rio Grande do Sul  - CIENTEC, under technical direction of
 Eng. José Germany and the technical work of the team of
Eng. Antonio Carlos Solano.
This apparatus was built  by a  proposal of Eng. Otto Albuquerque, at the time executive director of
This prototype is in exhibition  in the Center of  Permanent Educational
Foundation Father Landell de Moura - Ipiranga, av., 3501 - Porto Alegre
Rio Grande do Sul - Brasil - 90.160-001.
Specifications that form integral part of the Patent Letter N.771.917, dated of OCT. 11/1904
Solicitation  of February 9, 1903 - Series N. 142.440

"To whom it may concern:"

Know that me, Roberto Landell de Moura, citizen of the Republic of Brasil  resident in the district of Manhattan of New York city, New York State, invented a new Wave Transmitter, that makes the following specifications: My invention is related to Message Transmissions, from a point to another, without the aid of wires, or concisely the communicating through space.

It has the objective of producing better results with simplified apparatus, using certains principles that I discovered. Up to now, when we had to transmit signals, the transmission was made by means of apparatus of manual operation. In some cases, these were substituted by automatic mechanisms; but the handling of such mechanisms, or the manipulation of a key, demanding certain abilities and experience of the operator. In agreement with my invention, I produce, firstly, Electrics Oscillations and a Light Trembling, by means of Sound Vibrations, it can be of the Human Voice  or others sounds.

I use these Electric or Luminous Oscillations, so produced, to telephone or to telegraph through space . In such transmissions, and especially telephoning, I can use inventions similar to the ones that I described in my previous solicitation,  protocoled in OCT 04 - 1901, series N.77.576.To produce the two species of mentioned oscillations I invented a disposition of circuits and of certains apparatus that I denominated "phonetic switch". *Obs:Web comments: (a electro mechanical microphone).

My phonetic switch consists, essentially, of a pair of contacts capable of reproducing the sounds vibrations , or the vibrations from any source that can control the primary circuit of a high frequency induction coil, this primary is tied up to the primary of a Ruhmkorff coil for transmission.

The Sound Vibrations on the Fonetic Switch are transformed  in Electrics or Light Waves, the one which, passing to the receiving station, are received and act on appropriate apparatus, by means of which they are perceptible with the use of a Phone Receiver, of a lamp, of a Recording Morse, or similar thing. My invention is in full detail described in the following specifications, and illustraded in the enclosed drawings.
In relationship to fig.1 it is a cut of my phonetic switch , with the whole parts represented. In 2 the illustration represents a regulatory key for the nucleus of the induction coil. In 5 the circuits transmitters are represented with the apparatus; represented in their places. In 1 we have the box with non conductor material, and A' is the cover. This cover is made  to contain a Resonant Chamber, whose base has a perforated disk A2 and is sustained by the receptacle there is a diaphragm (a), having in their central point a slight depression. (a').

Placed inside of the receptacle and supported in appropriate projections, there is an Induction Coil, that has the primary (d) and the secondary (d') coiled around of the iron nucleus (d2).This nucleus is hollow, and in its interior a central axis exists (B) supported in its superior extremity by the perforated extremity of the nucleus and in its inferior extremity, it is connected inwardly by the nut (b) screwed in the inferior extremity of the nucleus, and the guide (b4). The axis has a head (B') which can be manipulated. The function of the adjustment is to allow that the narrow opening of air, between the extremety axis, in (b2) and the diaphragm (a), in (a'), be in such an arranged way that the vibrations of the articulated words produces a continuous, fast and regular movement, and interrupt the circuit. By means of key K (represented in 2), the nut (b) it can be screwed when the axis is adjusted, introducing the stems (k) and (k4), of the key in the holes (b3) of the nut.

Fastened in the superior extremity of the cover (A') a flexible tube exists (C) with a mouth (c).

To use the apparatus, the  operator speaks in agreement with a established code or in any other way, through the mouth (c).The propagation of the Sound Waves through the tube, passing  between of the central opening of the cover (A2) act over the diaphragm (a), producing a corresponding vibration, and in consequence if the adjustments had been correctly done, a fast series of contacts and interruptions or  successive contacts will happen between the diafragm and the extremity of (b2), corresponding the frequency to the waves that were produced.
These contacts and interruptions determine pulses or current variations , in the secondary circuits 12, being irradiated by the Antenna.

The production and the interruptions of contacts have as consequence, to produce current pulsations in the primary coil, corresponding very aproximately to the voice tones or the sounds produced.

Certainly, it is impossible to obtain an adjustment of such perfect contact that reproduces all the harmonics and turn a perfect articulation, but in the other hand, in order to get the positive effects, of discharge, the other that I will refer now I think to be best, other than the simple change of the circuit resistence. It is not necessary to say that  I can adjust  the contacts in such a way to produce constant contacts and variable pressure, requirements so that the microphone will work perfectly; but with practical intention, I think that is better  to produce the pulses in the way that I described.

Considering now (5), I will describe the connections of my apparatus, to obtain an effective  system.
F is a Ruhmkorff coil or any other induction coil of high potency, adjusted in way to produce a flash of certain length,  - let us say of about a 1/4 inch or more.  The primary of this coil (f) is tied up to the the circuit 15 and 16, that includes the main battery M and the phonetic switch. The secondary coil, marked (f') is connected by the wires 7 and 8 to the terminals 21 and 20 to the
irradiant wires, that can be of common form or any aerial conductor, with or without terminal
grounded in one of the sides.

 A terminal pair (11) and (12) to produce flash, is foreseen, to be inserted in the circuit (7) (8), by the simple closing of the switch (S'). It is also linked to the secondary circuit, a capacitor of convenient capacity. The primary circuit (15) (16) is going from the Ruhmkorff coil to the primary terminals of the induction coil (D), in the phonetic switch.

The secondary coil (d') is tied up to a local circuit (19), that contains a Phone Receiver (T), and the primary circuit includes a lamp, that can be used to transmit or to receive messages.  There is too a capacitor (G) of convenient capacity, inserted in the primary circuit. The way to use the described system,  is the following: To transmit electromagnetic waves corresponding to the Sound Vibrations, the key (S') is closed and the the key (S) is opened, and the operator starts to produce the wanted sounds, by means of the fonetic switch. A pulses succesions is so produced in the primary circuit coil (F), whose effect is increased by the presence of the capacitor (G), that absorbs the current excess, it contribute to the fast demagnetization of the induction coil and still disable the the production of flashes between the diaphragm and the point of the axis.

 These pulses in the primary are very fast , when the adjustments are appropriately done, they produce pulses of high potential in the secondary.

To produce Light Oscillations by means of the switch, in the transmitter station, I use the natural human voice, because the trembling produced corresponding in form and frequency to the initial sounds, and being these sounds produced in a convenient way with the aid of adequate apparatus, in the receiving station, they allow the recognition more ou less perfect of the  original sounds, and seen as a lot of words or tones can be recognized by its intrinsic value, as much as for any value that can be  lent by means of any arbitrary code, an enough number of different words can be selected, to constitute a complete and very efficient code.

Of course other sources of soundvibrations can be used to substitute the human voice. So, to produce electricoscillations by means of the same switch, it can be used in the transmitter station,
a constituted source of sounds by a musical instrument similar to a small organ , having a group of sheets or acoustic tubes tied up to the mouth (C). By the strong diaphragm vibration, it produces light oscillations or electricity that can be received, after  transmitted, by means of any sensitive apparatus. In addition to this transmission method by means of electromagnet  or  luminous waves, as I said, some of the particularities hereby described they can be used together with my other systems. In one of these systems, I use waves  or intermittent signals of light , to transmit codes signals.

 In the present case I can use the lamp (e), in a similar way, producing the initial variations of current by means of the phonetic switch. If the  light pulsations are fast, the adjustment  of the terminals and diaphragm can be regulated, untill the width of the variations is enough to eliminate all the tones less the fundamental ones. In fact more weight can be given to the diaphragm, if it necessary,  or its pulsations can be in another way, retarded. In the case of the transmission to be done by light waves , I use reflector and I can also use screens of several materials, such as sheets of colored glass, and it is possible to substitute the lamp indicated by a cathodic lamp, of the type described in my other solicitation, or other light types. 

Observe that the most important and, in fact, the essential aspect of my invention is the employment of a transmitter that turns on and and off by the effect of the sound vibrations, doing  the light waves or transmitted eletromagnectics waves corresponding , in a very approximate way, to the sound waves which are produced.


 Original Diagrams of the Wave Transmitter


Research Material:

The incredible Father Landell de Moura (Ernani Fornari), En El Aire: The Light That Talks (Otto Albuquerque), Landell de Moura (B.Hamilton Almeida), The Other Side of The Telecommunications - The Father Landell's saga - (B.Hamilton Almeida), The Man That Pressed The Button Of The Communication - ( Editora Feplam - Seg. Ediçao 1977). Special gratfulness to the friends Francisco Rodrigues Leite - Olegario Vargas - Sonia Rinaldi - Fernando H. de Oliveira - that collaborated sending material that are facilitating me study and research about the labour of our great countryman and cientist work. Special thanks to Arsenio Fornaro for English text version corrections.

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