US1418285A

US1418285A - Translating circuit

Info

Publication number: US1418285A
Application number: US257654A
Authority: US
Inventors: John R Carson
Original assignee: American Telephone and Telegraph Co Inc
Current assignee: AT&T Corp
Priority date: 1918-10-10
Filing date: 1918-10-10
Publication date: 1922-06-06
Anticipated expiration: 1939-06-06

Description

J. R. CARSON.

TRANSLATING CIRCUITS. APPLICATION-FILED 0m. 10, 1918.

1,418,285. Patented June 6, 1922 Modzlaiiny Source 7 y INVENTQR.

Jolmlfi Carson BY g a M ATTORNEY UNITED STATES PATENT o -"nca JOHN R. CARSON, 015 NEW YORK, N. Y., ASSIGNOR T0 AMERICAN 1 TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK,

Application filed October 10, 1918.

To all whom it may'concern:

Be it known that I, JOHN R. CARSON, residing at New York, in the county of New York and State of New York, have invented certain Improvements in Translating Circuits, of which the followingis a specification.

This invention relates to signaling systems, and more'particularly to systems in which carrier currents are employed for the transmission of signals.

The invention has for one of its objects the provision of a translating arrangement for modulating high frequency oscillations, the. modulating means comprising a two element vacuum tube or other equivalent device having unilateral conductivity. Another object of the invention is to provide an arrangement of this character capable of use either as a modulator of high frequency oscillations in accordance With signal Waves, or as a modulating'detector for detecting, in

accordance with the homodyne or'heterodyne' system of receiving, modulated high frequency oscillations transmitted from a distant station. Still another object of the invention has reference to the provision ofa translating arrangement of the character just described in which the 'unmodulated oscillations are ineffective upon the outgoing transmission circuit when the variable modulating source is inactive, so that when the arrangement is used as a modulator, the

amplitude of the transmitted oscillations will be directly proportional to theamplitude of the modulating waves.

"vacuum'tube'1',"having a heated filament 2, and an anodeor plate-3.- Aicircuit-comprising conduc'tors 4".andr5 is associated with thefilamentand' plate ofsaidtube, and at Other and further ob]e cts of the invention will be'apparent from the detailed description ofthe invention hereinaftergiven.

The invention may, now. be more fully understood from thefollowilng description thereof when read .inyconnection with the accompanying drawing, Figures 1, 2 and 3 of which representthree different diagrammatic embodiments .ofthe invention; I

Referring to Figure 1,. a translating de-q vice-is shown consisting.- of "atwo element points 6 and 7 said circuit divides, one path ffcontinuing throughga source of direct cur-I rent 8 and the secondary of a transformer 9, theother path including the second Specification of Letters Patent. Patented June 6, 1922.

Serial .No. 257,654.

12. A source of modulating waves 15 is associated with said first mentioned path by means of the transformer 9.

The modulating waves supplied over the circuit 15 may be either low frequency signaling waves or high frequency oscillations modulated by means of a signal and transmitted from a distant station, depending upon whether the arrangement is to be used for modulating'high frequency oscillations in accordance with the signal, or for detecting modulated high frequency oscillations transmitted from a distant station. If the arrangement is to be used for the former purpose, the operation is as follows:

I Oscillations from. the source 13 and low frequency signaling Waves from the circuit 15 are impressed upon the circuit ofthe tube 1 through the transfo-rmerslO and 9v predominant first curvature, the high frelatedby-means of signal waves at a distant stationare received over the circuit15, and areimpressed upon 'the tube 1 through the transformer 9; .High frequency oscillations from the source 13 are also impressed upon the tube through the transformer 10. If the heterodyne systemof receiving is employed, the frequency, of the source13 will be slightlydiflerent from'that received over the ,circuit 15, sov that waves of beat. frequencywill betransmitted through the transformer 12 to the outgoing circuit 1Q.

llVherethe homodyne system of receiving is employedpthe, frequencyof the. source 13 willbe-eq'ual tothatof the high frequency modulated oscillations; receivedinthe circuit 15, in which case variable low frequency waves corresponding to the signal by which the high frequency oscillations were modulated at the distant station, will be trans- 5 mitted through, the transformer 12 to the outgoing'circuit 14.

Where it is desired to prevent the source of unmodulated high frequency oscillations from affecting the outgoing circuit, except 1 when the modulating source is active, an arrangement such as illustrated in Figure 2 maybe employed. In this arrangement two vacuum tu es 16 and 17 are shown, having filaments 18*and 19, and anodes or plates 20 1 and 21 respectively. A source of direct current8 has one terminal connected to the

filamnts

18 and 19, andthe *other terminal is connected in parallel to the plates and 21 through the secondary windings of a trans- 20 former arrangement 22 through which the circuit 15 is associated with the

tubes

16 and 17. A source of high frequency oscillations 13-is associated bymeans of a transformer 10 with the common path 23 of two parallel 25

circuits

24 and 25, said parallel circuits, be-

ing connected to the

plates

20 and 21, and including the primary windings of a transformer arrangement 26, whereby an outgoing circuit 14 is associated'with the

tubes

16 and 17.

This arrangement is such that when the modulating source associated with circuit 15 is inactive, oscillations from the source 13 are ineffective upon the outgoing circuit 14,

I since the ,source of oscillations is applied to a bridge circuit which is balanced with re- 'specti to the outgoing circuit.- When how i ever, waves from the circuit-15 are applied. to the

tubes

16 and 17, the balance 1s dis-w 40 turbed, and oscillations will be transmitted through the transformer 26 to the circuit 14, having an amplitude proportional to the degree of the disturbance produced by the .waves from the circuit -15; If, therefore, the

, circuit 15 be associated with a source of low frequency signaling waves, the high frequency oscillations from the source '13 will be modulated in accordance with said waves by means of the tubes 16 and17, and modulated high frequency' oscillations will be transmitted through the transformer 26 to the circuit 14, the amplitude of said oscillations being directly proportional to the amplitude of the modulating signaling waves. Where the arrangement is to be usedas a modulating detector, modulated high frequency oscillations will be received from the circuit 15, and transmitted through the transformer 22 to the

tubes

16 and 17 Oscillations from the source 13 will interact with the received oscillations in the tubes 16 and'1'7 and low frequencysignals will be transmitted "through the transformer 26 to the circuit 14. These low frequency signal waves will be of beat frequency where the the case of the circuit arrangement of Figure changed with respectto the

tubes

16 and 17. A

The outgoing-circuit'14 is associated by means of a transformer 27 with the common branch 23 of the two

parallel circuits

24 and 25, while the source of oscillations 13 is associated by means of a transformer arrangement 28 with the individual paths of said parallel circuits.

In accordance with thisarrangement, the circuits are normally balanced sothat oscillations from the source 13 are ineffective upon grid circuit 23, and consequently do not react upon the outgoing circuit 14. When the balance is disturbed by waves from the circuit 15, energy is transmitted to the circuit 14 in direct proportion to the amplitude of-,the disturbing waves. As in 2, the circuit of Figure 3 may be employed either, for modulating high frequency os cillations from the source 13 in accordance with low frequencysignals impressed upon thecircuit 15, or for the purpose of detecting high frequency modulated oscillations impressed upon the circuit 15 in accordance with either the homodyneor heterodyne principle of receiving.

By means of the circuit arrangement above described, a simple and yet efiicient modulating arrangement is provided, which is quite flexible in its operation and is readily adapted to a considerable number of uses. It will also be obvious that the general principles herein disclosed may be embodied inma'ny other organizations widely different from those illustrated Without departin from the spirit of; the invention as define in the following claims:

What is claimed is:

1, In a signaling system, a duplex translating device comprising two elements hav ing unilateral conductivity, parallel circuits for each of said elements having common 120 branches connected to said elements, a source of vunmodulatedoscillations and an outgoing circuit associated with one pair of said parallel circuits, and a source of variable oscillations associated with the other pair 125 of parallel circuits.

2. In a signaling system, a duplex translating device comprisin two elements havparallel circuits for each of said elements having common branches connected to the 'filaments and anodes of said elements, a

oscillations associated withthe other pair of parallel circuits.

3. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, parallel circuits for each of said elements having common branches connect'ed'to said elements, a source of unmodulated oscillationsand an outgoing circuit associated with one pair of said parallel circuits, and a source of modulating signal waves associated with the other pair of parallel circuits.

4. In a signaling system,a duplex translating device comprising two elements having unilateral conductivity, and each including a heated filament and an' anode, parallel circuits for. each of said elements having common branches connected to the filaments and anodes of said elements, a source of unmodulated oscillations and an outgoing circuit associated with one pair of parallel circuits, and a source of modulating signal waves associated with the other pair of parallel circuits.

5. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, parallel circuits for each of said elements having common branches connected to said elements, a source of unmodulated oscillations and an outgoing circuit associated with one pair of said parallel'circuits, and a source of variable oscillations associated with the other pair of parallel circuits, and connections between said sources, said outgoing circuit and said input and output circuits whereby said first mentioned source produces no effect upon said outgoing circuit when said second mentioned source is inactive. I

6. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, and each including a heated filament and an anode. parallel circuits for each of said elements having common branches connected to the filaments and anodes of said elements, a source of unmodulated oscillations and an outgoing circuit associated with one ,pair of parallel circuits, and a source of variable oscillations associated with the other pair of parallel circuits, and connections between said sources, said outgoing circuit and said input and output circuits whereby said first mentioned source produces no effect upon said outgoing circuit when said second mentioned source is inactive.

7. In a signaling system, a duplex translating device comprising two elements havingunilateral conductivity, parallel circuits for each of said elements having common) branches connected to said elements, a sour :e of unmodulated oscillations and an outgoing circuit associated with one pair of said parallel circuits, and a source of modulating signal waves associated with the other pair of parallel circuits, and connections between said sources, said outgoing circuit and said input and output circuits whereby said first mentioned source produces .no effect upon said outgoing circuit when said second mentioned source is inactive.

' 8. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, and each includ ing a heated filament and an anode, parallel. circuits for each of. said elements having common branches connected to the filaments and anodes of said elements, a source of un modulated oscillations and an outgoing circuit associated with one pair of parallel circuits and a source of modulating signal WH/VBS associated with the other pair of parallel circuits. and connections between said Sources, said outgoing circuit and said input and output circuits whereby said first mentioned source produces no efiect upon said outgoing circuit when said second mentioned source is inactive.

9. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, circuits for said unilateral elements, individual branches and a common branch, :1 source of unmodulated oscillations and a source of variable oscillations, one of said sources being associated with the common branch of said circuits and the other circuit being associated with the individual branches thereof, and an outgoing circuit associated with said translating device.

10. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, each elementineluding a heated filament and an anode, circuits for said elements having a common branch and individual branches, the common branch being connected to said fila-' ments and the individual branches being connected to said anodes, a source of unmodulated oscillations and a source of variable oscillations, one of said. sources being associated with the common branch and the other source being associated with said individual branches, and an outgoing circuit associated with said translating device.

11. In a signaling system, a duplex translating device comprising two elements having unilateral conductivity, circuits for said elements, said circuits having a common branch and individual branches, at source of modulated oscillations and a source of modulating signal waves, one of said sources being associated with said common branch said circuits including and the other source being associated with said individual branches, and an outgoing Waves, one of said sources being associated circuit associated with said device. a I with said common branch and the other 12. In a signaling system, a duplex trans- 7 source being associated with said individual lating device comprising two elements havbranches, and an outgoing circuit associated 5 ing unilateral conductivity and each includ- With the said device. 15

ing a heated filament and an anode,'circuits In testimony whereof," I have signed my for each'of said elements, said circuits havname to this specification this 7th day of ing a common branch and individual October 1918. branches, a'source of unmodulated oscilla- 10 tions and a source of modulating signal .JOHN R. CARSON.