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Publication numberUS1252520 A
Publication typeGrant
Publication dateJan 8, 1918
Filing dateApr 2, 1915
Priority dateApr 2, 1915
Publication numberUS 1252520 A, US 1252520A, US-A-1252520, US1252520 A, US1252520A
InventorsRoy A Weagant
Original AssigneeMarconi Wireless Telegraph Company Of America
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Wireless signaling apparatus.
US 1252520 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)




1,252,520I Patented Jan. 8, 1918.

Q I w W WQ W nor A. wnnenn'r, or nosnnnn, new JEBSEY, nssiendn 'ro anson: wmnnnss 'rntnennrn concrniw or memos, on NEW irons, n. Y., a oonrona'rron or new JERSEY.

wmnnnss SIGNALING 'arranarus.

Specification of Letters Patent.

Application filed April 2, 1915. Serial 1%. 1am.

' town of Roselle, county of Union, State of Well-known Fleming valve shown a New Jersey, have made certain new and useful Improvements in Wireless Signaling Apparatus, of which the following is a speci-\ fication.

The invention is an improvement on the scribed in U. S. Letters Patent No. 03684, dated November 7th, 1905. In this improved apparatus shown and described herein, there is employed a vacuum chamber containing a hot element and a cold element and outsidethe chamber an elementis fixed in position, this element has extended capacity area and is in close proximity to the outer surface; the outer element is preferably metal, like copper, arranged with its surface area 'approx'nnately parallel with the path of electrons moving from the hot element at one end toward the cold element at the other end of the chamber; this outerelement is of suficient area to surround both elements, and the space between said elements; the object being to establish an extensive and intimate relation between the path of electrons and the surface of the outer element. As shown and described herein, the apparatus can be operated to. generate groups of oscillations following each other at any which intervallmay. either within or without the range of; aludibility. By reason of this action whenadjustinents are so made that these groups of oscillations follow each other at a rate"which' is'nearly or quite beyond the upper limit ofaudibility, the de vice damped oscillations, due a, the fact that the oscillation frequencyof groups may be so adjusted as tobe slightly difierent from that of the incomiingzignals; the free sult produced being a beat ween these two trains of oscillations, producing an audible note in the telephone receiver of any desired pitch. This result is due jt'othe fact that with the described arrangement, the'v'alve automatically opens "and closes the battery circuit at a rate which depends on adjustment of the constants of the circuit, the establishment of the reg-iced filament temperature, and the ;*.-nt of a valve d de-' desired; time interval,

becomes a receiver of continuous or un'-' exhausted to the proper degree. Generally speaking, the vacuum should be such that the application of 100 volts or less between 'the-inclos'ed terminals will produce a visible blue glow or arc like eilect. The oscillation frequency, however, is controllable by means of the associated oscillation circuit, which includes the well-known tuning elements; that is, adjustable inductance and adjustable capacity, and the electrical association of this circuit with the outer; element of the valve.

The utility of the resistance and the ca- I pacity shunting1 the resistance in the battery circuit is Patented Jan, 8, 1918. I

at it supplies amplification of the efi'ect of small electrical impulses impressed upon the valve. When this resistance, which is very high, and of the order of that of the valve itself, is employed, an

adjustment of the potential of the battery to attaining the condition of automatic interruption of the battery circuit previously-referred to, which enables the valve to operate as a generator of groups of oscillations which have a period determined by the res'ultant eil'ect of the periodicities ofthe associated circuits upon one another. 'The thecry of this action appears to be as follows:

7 When the battery circuit is closed the temperature-of the filament being assumed to be correct, the current starts to flow throu h the battery circuit; as this current builds 1%), however, a considerable roportion of the electro-motive orce is consumed impressgds in the istance outside of ,the valve with the result that as greatly reduced, so that'the circuit, efiect,

I the current, flow through I the valve from-the battery increases, the po tential across the electrodes within the valve, decreases and when all conditions are prop-' erly adjusted this decrease appears (to be of the battery circuit, said battery circuit nasaaao 6. In a wireless signaling apparatus, comprlsing an antenna and an antenna clrcult, the combinatlon with a vacuum valve having a hot elementand a cold element within the chamber and an electrostatic control element outside said chamber, adapted to project a field of force intothe space within the chamber, a coil associated with the antenna circuit, a local circuit, a capacity in said circuit in parallel with said coil, an electrical connection between the terminalof said coil and said outside valve element, an electrical connection between said coil and a point in aving its terminals connected to the two elements within thechamber, respectively, and including a battery, a resistance, and a capacity in parallel with said resistance.

7. A vacuum chamber containing two elements, means for heating one of said ele meuts, a conducting terminal located outside said'chainber in close proximity to the direct line of movement of electrons in said chamber, an oscillation circuit having its termi- 8. In a wireless signalin apparatus, the

, combination of a vacuum 0 amber'containing two elements, means for heating one of said elements, a local circuit comprising a battery and a non-inductive resistance, each shunted by a condenser, said circuit being connected to said elements and adapted to produce an electron stream between the same, an electrostatic control element outside said chamber, the field of force of outside element being at an angle to the electron stream, and a tuned circuit connected to said outside element and to one of the interior elements, all for the purposes described.


U.S. Classification455/331, 331/42, 329/322, 313/597, 331/184
Cooperative ClassificationH03D7/02