US1394056A

US1394056A - Signaling system

Info

Publication number: US1394056A
Application number: US393812A
Authority: US
Inventors: William C White
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1920-07-03
Filing date: 1920-07-03
Publication date: 1921-10-18
Anticipated expiration: 1938-10-18

Description

- W. C. WHITE.

SIGNALING SYSTEM. APPLICATION FILED JULY 3. 1920.

Patented Oct. 18, 1921.

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uurrsl) STATES PATENT orrica- WILLIAM 0. WHITE, OE SCHENECTAJJY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

SIGNALING SYSTEM.

Specification of Letters Patent.

Patented Oct. 18, 1921.

Application filed July 3, 1920.- Serial No. 393,812.

To all whom it may concern:

Be .it known that 1, WILLIAM vC. WHITE, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Signaling Systems, of which the following is a specification.

My present invention relates to signaling systems, and more particularly to systems for transmitting signals by means of high frequency currents.

The object of my invention is to provide a simple and eflicient system for transmittin high frequency signaling currents in which the energy for the operation of the system is derived from a source of alternating current of the usual commercial low frequency.

In my Patent 1,195,632, August 22, 1916, I'have described a transmitting system for radio signaling in which the energy for the operation of the system is derived from an alternating current source of low frequency. In this case, rectifiers are provided for rectifying the low frequency current and thus furnishing a direct current for the operation of electron discharge high frequency oscillators and modulators.

I have now discovered that by suitable circuit arrangements the rectifiers in such a system may be entirely J dispensed with and the rectifying properties of the oscillating and modulating devices themselves may be utilized for producing the desired rectification of the low frequency current.

Thenovel features which I believe to be' for supplying energy for the operation of.

the electron discharge oscillators 2 and 3, and the modulators 4 and 5, these oscillators and modulators being preferably of the usual three-electrode high vacuum type. Current for heating the'filamentary cathodes of the oscillators and modulators is also derived from the source 1, being supplied to the cathodes by means of the transformer 6, the middle point 7 of which is preferably grounded. Current for the operation of the oscillators and modulators is supplied to the plate circuits by means of the transformer 8, the secondary of transformer 8 being oppositely connected to theplate circuits of the oscillators 2 and 3 as well as to the plate circuits of the modulators 1 and 5. The plate circuits of the oscillators and modulators are all completed by a connection from the middle point 9 of the secondary of the transformer 8 through a reactance 10 to ground at 11. The circuit by which energy is supplied for the operation of the oscillator 2 may be traced out as follows:

rom ground 11 through high inductance 10, through one-half of the secondary of the transformer 8, radio choke coil 11, anode 12, cathode 13, back to earth at 7. The circuit by which energy is supplied for the operation of the oscillator 3 mcludes the other half of the secondary of transformer 8 and a radio frequency choke coil 14. The circuit by which energy is supplied for the operation of the modulator 4 starting from ground 11 includes the high inductance 10, one-half of the secondary of the transformer 8, plate 15, cathode 16, back to earth at 7. The plate circuit of the modulator 5 is supplied With energy from the other half of the transformer 8. In shunt to the cathode and anode of oscillators 2 and 3, circuits are connected through which the high frequency currents circulate made up of condensers 17 and 18 for preventing low frequency currents from flowing in the circuits and the inductance 19, which is common to both circuits. The grid circuits of the oscillators 2 and 3 both include the inductance 20 cou- 1 pled to the inductance 19 and the usual grid the high frequency current in the antenna is effected by impressing the modulating current upon the grid circuits of the modulators 4 and 5. In the present case I have indicated as a means for impressing the signaling current upon the grid circuits of these modulators the local circuit of the oscillators and the modulators.

potential suitable for the best operation of the modulators.

It will be observed that the inductance 10 is common to the plate circuits of boththe When a slgnaling current is impressed upon the grid circuits of the modulators the potential drop across the inductance 10 varies in accordance with the variations in the signaling current and the potential supplied to the oscillating circuits of the oscillators 2 and 3 varies accordingly thereby producing a corresponding modulation of the high frequency current produced in the antenna. .The

inductance 10 also acts to smooth out the low frequency variations in the current sup:

' plied to thejoscillators and modulators. By

' high *frequency'currents generated and of .ulator tubes 4 and 5. A of the coupling coils 19 and 20 is connected proper" design ofthis inductance I have i found that the variations in this current supply may besmoothed out to such an extent as. to introduce no objectionable low frequency variations in I the modulated high frequency current. r

The radio frequencychoke coils 11" and 14 serve the double purpose of protecting the secondary of the transformer 8 from the preventing these high frequency currents from being short circuited through the mod- One terminal of each toearth at 11-. and as a result although the low frequency potential applied to the system from the secondary of the transformer- 8 may be very high, the low frequency po--- tentials set up in the coils 19 comparatively low.

While I have indicated only one circuit arrangement whereby my invention ma be carried into -effect, it will be obvious to t ose and 20 will be skilled in the art that many-variations in the circuit. connections used and in: the form of the apparatus employed may be made without departing fromthe scope of my invention as set forth in the appended claims.-

6 5 -2. The combination '1 a high frequency What I claim as new and desire to secure by- Letter's Patent'of the United States, is,

1. The combination in "a high frequency signaling system of a pair of electron discharge devices having coupled plateand.

grid circuits, a source of low frequency alternating current oppositely connected to,

the plate circuits of thetwo devices, asecond pair of electron discharge devices .hav-

ing plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuits of the second pair of devices, and an inductance which is common to the'plate-ci-rcuits of'all of the devices. i

' common to the cuits, said source of low frequencycurrent being also oppositely connected to the plate circuits of the second pair of devices, and an inductance which is common to the plate circuits of all of the devices.

3. The combination in a high frequency signalingsystem of a pair of electron discharge devices having coupled plate and grid circuits, a source of low frequency alternating current oppositely connected to the plate circuits of the two devices, a second pair of electron discharge devices having plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuits of the second pair of devices, means for impressing signaling currents upon the grid circuits of the second pair of devices, and an inductance which is I plate circuits of'all of the de- V1088.

4. The combination in a high frequency transmitting system,'of anantenna, a pair of electron discharge devices having coupled plate and "grid circuits for producing radio frequency oscillations in said antenna, a source of low frequency alternating current oppositely connected to theplate circuits of the two devices, a second pair of electron discharge devices having plate and 'grid circuits, said source of low frequency-current vbeing also oppositely connected to the plate circuits of the second pair of devices, means for impressing signaling currentsnupoifthe grid circuit of the second pair of devices, and an inductance which is common to the plate circuits of all of the devices.

5. The combination in a high frequency slgnaling system of a. pair of electron discharge. devices having coupled plate and grid circuits, a source. of low frequency alternatlng current oppositely connected to the plate circuits of the two devices, radio frequency choke coils in the. plate, circuits of said devices, a second pair of electron dlschar'ge devices having plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuits of the second pair of devices, and

" an inductance Which is common to the plate circuits of all of the devices. I

6.'.The combination in a high frequency transmitting system, of an antenna, a pair of electron discharge devices having coupled plate and grid circuits for producing radio frequency oscillations in said antenna, a source of low frequency alternating current oppositely connected to the plate circuits of Ill the two devices, radio frequency chokecoils in the plate circuits of said devices, a econd pair of electron discharge devices having plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuits of the second pair of devices, means for impressing signaling currents upon the grid circuits of the sec-' I coupling inductances being rounded, a

source of low frequency alternating current oppositely connected to the plate circuits of the two devices, a second pair of electron discharge devices having plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuit of the second pair of devices, and an inductance which is common to the plate circuits of all of the devices.

8. The combination in a high frequency transmitting systemof an antenna, a pair of electron discharge devices having" inductively coupled plate and grid circuits for producing radio frequency oscillations in said antenna one terminal of each of the coupling inductances being grounded, a source of low frequency alternating current oppositely connected to the plate circuits of the two devices, a second pair of electron discharge devices having plate and grid circuits, said source of low frequency current being also oppositely connected to the plate circuits of the second pair of devices, means for impressing signaling currents upon the grid circuits of the second pair of devices, and an inductance which is common to the plate circuits of all of the devices.

9. The combination in a high frequency signaling system of a pair of electron discharge devices having coupled grid and plate circuits, a source of low frequency alternating current oppositely connected to the plate circuits of the two devices and means for varying in accordance with a ignaling current the potentials applied from said source to the electrodes of said devices.

10. The combination in a high frequency signalin system of an antenna, a pair of electron discharge devices having coupled grid and plate circuits for producing radio frequency oscillations in said antenna, a source of low frequency alternating current oppositely connected to th the two devices, and means for varying in accordance with a signaling current the potentials applied from said source to the electrodes of said devices. In witness whereof I have hereunto set my hand this first day of July, 1920.

WILLIAM C. WHITE.

e plate circuits of