US2339293A

US2339293A - Telegraph transmitter

Info

Publication number: US2339293A
Application number: US434554A
Authority: US
Inventors: Albert H Reiber
Original assignee: Teletype Corp
Current assignee: AT&T Teletype Corp
Priority date: 1942-03-13
Filing date: 1942-03-13
Publication date: 1944-01-18
Anticipated expiration: 1961-01-18

Description

muzmuwz 2 Sheets-Sheet 1 ATTORNEY A. H. REIBER TELEGRAPH TRANSMITTER Filed March 13, 1942 n can: -a- 11-! I 0 @9006 0-95 a Jan. 18,- 1944.

Jan. 18, 1944.

A. H. REIBER TELEGRAPH TRANSMITTER 2 Sheets-Shet 2 Filed March 13, 1942 muzmuum MON mmu w INVENTOR ALBERT H. REl-BER RVs 7. 5

ATTORNEY Patented Jan. 18, 1944 TELEGRAPH TRANSMITTER Albert H. Reiber, Evanston, 111., assignor to Teletype Corporation, Chicago, 111., a corporation of Delaware Application March 13, 1942, Serial No. 434,554

20 Claims.

This invention pertains to printing telegraph systems and apparatus and more particularly to transmitters for sending monopulse isochronous code signals.

The principal object of the invention is to provide a transmitting arrangement for automatically sending standard or fixed messages.

Another object of the invention is to provide a monopulse transmitting system combining a keyboard transmitter and automatic means for transmitting standard or predetermined phrases.

In accordance with the present invention, a keyboard transmitter of the type exemplified by U. S. Patent No. 2,173,147 issued September 19,

1939 to W. J. Zenner is utilized to send the ad- 3:

dress portion or changeable portion of a message, and a brush type distributor arrangement is employed to send certain predetermined fixed or standard phrases to be incorporated in a complete message to be transmitted. After the changeable portion of the message has been transmitted by the keyboard transmitter, a special key identifying the standard phrase is operated, whereupon transmission proceeds automatically under the control of the brush type distributor and the progress switches, associated with the standard message, to transmit monopulse code signals over the line until the standard phrase transmission has been completed, after which the keyboard transmitter, if the message is not concluded, is again operated for its remainder or closing portion of the message.

More specifically, the principle involved in the adaptation of a brush-type distributor to monopulse isochronous code signal transmission is that when the brush arm leaves the stop segment, the line current becomes zero, thus initiating the no-current or spacing portion of the monopulse code signal. Then, when the brush reaches the conditioned or energized segment corresponding to the character to be printed, an impulse is generated Which energizes a magnet which looks up, and in looking up it controls continuous current on the signal line for the remainder of the revolution of the brush, thus providing the marking current portion of the monopulse code signal, irrespective of the condition of the remaining segments on the distributor. Moreover, the sequence of the characters making up the word in a standard phrase is governed by a multiple contact relay interposed between a stepping or progress switch and the segments of the brush type distributor, a relay being allotted to each standard phrase.

A more complete understanding of the foregoing objects and features of the invention may be had from the following description when taken in conjunction with the accompanying drawings, wherein like reference characters indicate the same parts throughout, and wherein,

Fig. 1 represents a schematic circuit having embodied therein the principles of the present invention;

Fig. 2 is a graphical representation of a signal of the monopulse type employed in operating printers of the class disclosed in U. S. Patent No.

2,147,075 issued February 14, 1939, to W. J. Zenner; and

Fig. 3 is a schematic circuit of another form of the present invention.

Monopulse signals may be composed of current and no-current signal conditions, and as may be understood by referring to Fig. 2, the transmission of monopulse signals of the type contemplated involves the interruption of a normal line condition for a measured interval which is initiated at a point definite with respect to each transmission cycle and is continued until the distributor has attained a position in the cycle which corresponds to and is identified with the particu-- lar character transmitted. At the termination of this impulse, normal line current condition is restored as indicated at the character W in Fig. 2. Normal line current is maintained thereafter until the arrival of the succeeding start instant, when, if a succeeding character is in readiness for transmission, another line interruption is thereat repeated. The alternative (normal and character impulses) line conditions may, if preferred, be comprised of positive and negative signals, or they may be comprised of either polarity of current as one line condition with no current as the alternative line condition. Variations of signaling practice along these lines would not be inconsistent with the structural principles disclosed in the present invention.

It is at times desirable to facilitate the transmission of information containing or embracing general statements or words, and therefore to simplify this practice, this invention contemplates the provision of means for introducing such standard or general phrases into the transmitted messages. Thus, if it is desired to send the following message Mr. Foxwanted on the phone, the name Mr. Fox will be transmitted over the line by operating a keyboard transmitting device I l of the type shown in U. S. Patent No. 2,173,147, after which a key I2 is depressed, which initiates the transmission of the fixed or standard phrase wanted on the phone through the instrumentality of a control unit tributor indicated generally as M. The keys l2 l3 and a brush-type disand |5 may constitute two keys of a bank of keys which may be arranged adjacent to the keyboard device H, Each of the keys of said bank of keys is allotted to a standard word or phrase. For example, key l5 may relate to the phrase please call your office and be connected to the unit |5, the operation of which initiates the transmission of the fixed phrase assigned to term according to the present invention is also adapted to automobile parking and call systems, wherein the license numbers constitute the variable or changeable information to be transmitted by the keyboard device H, and the name of the make of the automobile constitutes the fixed information to be transmitted under the control of units corresponding to units l3 and it.

The units l3 and I5 are representative of a group of units for controlling the transmission of standard phrases, and accordingly only the units I3 and I5 of the present embodiment will be herein described in detail.

The unit I3 contains a step-by-step or progress switch which comprises an arcuate series of contacts I1 and a corresponding series of contacts l8, and a pair of contacting arms H! and 2| mounted on a shaft 22. Also mounted on shaft 22 is a stepping ratchet wheel 23 which cooperates with a pawl 24 pivotally carried on an armature 25 of a stepping magnet 25. Contacts |8 of the progress switch are connected serially in the order of sequence of characters and word spaces in the fixed message or phrase to the segments 21 of ring 28 of distributor l4. For example, contact 79 allotted to the first letter W of the first word of the fixed phrase is connected by conductors 29 and 3| to the segment 30 of ring 28 allotted to said character, the conductors 29 and 3| being connected in series with a contact 32 of a gang relay 33. The conductor 3| extends through a cable 34, as do all the conductors similar to conductor 3|. Gang relay 33 comprises an electromagnet 35 having a pluralityof contacts ber'of characters and word spaces in the standard phrase assigned thereto. In addition to the plurality of contacts 32, the gang relay 33 is provided with a contact 3!! which is effective, as will hereinafter appear, to control the circuit for the stepping magnet 26 of its associated progress switch.

The distributor |4 comprises in addition to the segmented ring 28, the solid rings 35, 31, and 38 and the segmented rings 39 and 4|. Distributor I4 is also provided with a brush arm 42 carrying brushes 43 to 48, inclusive.

Brushes

43 and 44 cooperate with rings 28 and 35, respectively, and are connected by a conductor 48,

brushes

45 and 45 cooperate with

rings

37 and 39, respectively, and are connected by a conductor 5|, brushes 41 and 48 cooperate with rings 38 and 4|, respectively, and are interconnected by a conductor 52, and brush arm 42 cooperates with the armature 53 of a stop magnet 54. The ring 28 is provided with a stop segment 55 which is normally connected to battery as shown, and a start segment 56 to which no current is applied. Ring 36 or distributor i4 is connected by conductor 51 to a magnet 58. Conductor 57 also has a juncture with a conductor 59 for a purpose which will hereinafter be described. Ring 31 of distributor I4 is connected to battery as shown, and the lower portion of segmented ring 39 is connected by a conductor 6| to the armature 62 that key. The sys- 32 of a number at least equal to the numof magnet 58. Armature 62 cooperates through contact 53 with the winding of magnet 58 and also with the conductor 59. Ring 38 is connected by conductors 84, 55, and 55, and the afore-mentioned contact 35 of gang relay 33 to the winding of the stepping magnet 25 of the progress switch contained in unit H3. The lower segment of ring 4| is connected by a conductor 65 to the first contact 61 of the series of contacts H of the progress switch shown in unit l3. Stop magnet 54 associated with the brush distributor is connected by a conductor 68 to the conductor 65.

The contacts H, included in the standard phrase or word identified with the particular unit l3, are connected serially by a conductor 69, and the last contact in the word or phrase is connected'by a conductor H to the winding of the gang relay 35. The conductor B9 is shown in Fig. 1 as being connected to only those contacts I1 embraced in the word wanted. This is solely for the purpose of illustrating the present invention, it being understood that all of the contacts embraced in the entire standard or fixed phrase; for example, wanted on thephone, are serially connected by the conductor 69. The unused contacts are connected serially by a conductor l2, and the last contact of this unused series is connected by a conductor 13 to a normally closed contact 14 which is connected to the conductor 65. Armature 25 of magnet 26 is provided with an extension adapted to operate the contact 14 upon energization of the magnet 26 as will presently appear.

General operation In its stop or unoperated condition, the stop magnet 54 of distributor I4 is unenergized and hence the stop arm 53 is spring held in its clockwise position to block the movement of brush arm 42 and to hold the brush 43 in contactual engagement with stop segment 55 of ring 28. In this position of brush arm 42, current is applied to the signal line from battery, through stop segment 55, through brush 43, over conductor 49, through brush 44, over ring 35, over

conductors

51 and 59, through contact "I5 (which is analogous to contact of the keyboard transmitter disclosed in the afore-mentioned Patent No. 2,173,147), then over the signal line to the receiver 16 (which may be a printer of the type shown in U. S. Patent No. 2,147,075), thence to ground. Such a condition of the signaling line is the normal, idling condition of a telegraph line wherein the condition is said to be marking; that is, current on the line. In this condition, the magnet 58 remains energized over the afore-described circuit up to and including the conductor 51, from thence the current divides and extends through the winding of the magnet 58 to ground, thereby causing the armature 62 to be attracted to close the contact 83, which at this time however, has no effect, but the purpose of which will be later explained in detail. Assuming that the following message is to be transmitted, namely, Mr. Fox, wanted on the phone, the operator will operate the keyboard transmitter l to transmit over the signaling line to the receiver 76 the name Mr. Fox. Following the operation of the keyboard II in this manner, the operator turns to the special bank of keys, including keys l2 and I5, and operates key l2. The operation of key |2 effects the closing of contact 11 to complete an energizing circuit for the stepping magnet 25, which circuit, as seen from the drawings, is an obvious one. The

effect of energizing magnet 25 is to attract the armature 25 and to move the pawl 24 leftwardly (as viewed in Fig. 1) to pick up the next toothon the ratchet wheel 23. Then, when the key i2 is released by the operator, the current of the stepping magnet 25 is cut off, thereby permitting spring 78 to bias the armature 25 clockwise, and to move the pawl 24 to the right to step the ratchet wheel 23 clockwise to bring the contact arms is and 2| on shaft 22 into their first operating position in engagement with

contacts

67 and 79, respectively.

When contact arm i9 is brought into engagement with segment 67, a circuit is completed for the start magnet 54 of the distributor I4 from battery, through shaft 22, over contacting arm l9, through contact 61, over conductors B6 and 58, thence through the winding of magnet 54 to ground, as a result of which magnet 54 is energized so as to attract its armature 53 to thereby effect its disassooiation from the brush arm 42, thus permitting the brush arm 42 to rotate through the instrumentality of a friction clutch (not shown) as is customary in such distributing devices. Also, substantially simultaneously with this action, a circuit is completed for the gang relay magnet 35 from battery, through shaft 22, over contacting arm 19, through contact 8?, over conductors 69 and H, thence through the winding of magnet 35 to ground. At the same time as contacting arm is stepped onto the contact 67, the contacting arm 2| is also stepped onto the contact 19 which, in the present embodiment is representative of the character W which is the first character of the first word of the fixed or standard phrase to be transmitted. A circuit then is prepared from battery, over shaft 22 and contacting arm 2!, through contact 19, over conductor 29, through contact 32 (now closed), thence over conductor 3| (which extends through cable 34) to the segment W on the ring 28 of the distributor I l. The energization of magnet 35 of the gang relay 33 caused all of the contacts 32 thereof to close, thus closing at contact 32 the portion of the afore-mentioned circuit which extends from the contact 79 to the segment W on the ring 23. Also, contact 33 is closed at this time to prepare a circuit, hereinafter described, for the energization of stepping magnet 26 of the progress switch of unit 13.

Thus, as the brush arm 42 begins to rotate, the marking condition obtains in the signal line until the brush 53 leaves the segment 55 and passes onto the blank or unenergized segment 56, which is commonly known as the start segment. When the brush arm 52 leaves segment 55, the current in the signaling line is removed and the line is said to be in a spacing or no-current condition, and the magnet 55 is thus tie-energized and the armature thereof is released, thereby opening contact 53, the function of which will hereinafter appear. Also, the selector magnet in the receiving printer I is tie-energized, thus permitting the rotation of its type Wheel as described in the afore-rnentioned Patent No. 2,147,075. The spacing condition of the signaling line thus continues as the brush arm proceeds to rotate across the start segment 55 and segments 27 of ring 23, none of which is energized except the segment W, previously described as being in a prepared circuit. Then, when the brush 43 of the brush arm 22 engages segment W on the ring 28, the aiore-mentioned circuit which was prepared through the contact T5 and over the con ductor 3i is completed through brush 43, over conductor 49, through brush 44,- over distributor ring 35, thence over

conductors

51, and 59, through contact 15 and over the signaling line to the receiving magnet of the receiving printer-15.

As described in the afore-mentioned Patent No. 2,147,075, the selecting magnet in the receiving printer will at this time become energized to effect printing of the character, at which time the type wheel will be rotated to present the character W thereon to the printing point. Also at this time, the afore-mentioned circuit which was traced through the segment W and over ring 36 will also be completed through the-magnet 58 which will be energized to attract its armature 62 and close its contact 53 thus locking up the magnet 58 in a circuit extending from battery, over distributor ring 31, through brush 45, over conductor 5|, through brush 46, thence through the lower portion of distributor ring 39, over conductor 6i, through armature 62 and contact 63, thence through the winding of magnet 58 to ground. The magnet 58 is therefore locked up, and as the brush 43 passes offthe segment W, and breaks the circuit through the contact 79 and segment W, marking current will remain on the line through the instrumentality of closed contact 53 under the control of the magnet 58. The signaling line thus remains in an energized condition as the brush arm 42 continues its rotation back to'the stop segment 55 in readiness to initiate another rotation for the transmission of a succeeding character,

Referring to Fig. 2 which illustrates graphicaliy a monopulse isochronous code signal, the various conditions obtaining during the transmission of the code signal can now be readily understood from a review of the previously described rotation of the distributor arm 42. For example, the graphical representation above the line indicates marking current, and the representation below the line indicates no-current or spacing current. Thus, as-viewed in Fig. 2, the normal condition of the signaling line is markmg (i. e., current on the line) and as the magnet 54 is energized and the brush arm begins its rotation, a start condition (which is no-current or spacing) obtains on the line, and this condition continues until the brush arm reaches the segment representative of the character W, which condition is represented in Fig. 2'by the shaded portion below the center line XX, and indicates the continuance of a spacing or nocurrent condition until the character W is reached, whereupon the signaling line is again energized with marking current as indicated by the shaded portion above the line X-X, which shaded portion continues as graphically shown until the stop condition is again reached at the end of the code signal interval. The marking condition of the signal from W to the end of the signal which is the stop condition is obtained over the distributor ring 31, as previously described, by virtue of the locking up of the magnet 53.

As the

brushes

43 and 45 leave segments 28 and 56 of ring 33, respectively, the brush 46 will, when the brush 43 rests on the stop segment 55, rest on the blank segment 8! of ring 39, whereby the current for magnet 58 is no longer obtained through the rings 3'! and 39, but only through the stop segment 55 and ring 35. It is understood that brush 43 must contact segment 55 by the time brush 45 leaves segment 43.

During the complete rotation of the brush arm 42, not only was the monopulse code sign'al'for the character W transmitted, but also, a condition was set up for stepping the progress switch to its next contact preparatory to transmitting the second character A of the first word Wanted of the standard phrase. Thus, as the brush arm travels approximately two-thirds or three-fourths of its cycle of rotation, its brush 48 encounters the lower or energized segment of the ring 4| so that a, circuit was completed for the energization of stepping magnet 25 from battery, through shaft 22, over contacting arm l9, through contact 61, thence over conductor 65, through ring 4 I, then through brush 48,0ver conductor 52, through brush 41, over ring 38, then over conductors 64 and 65, through'contact '30 (now closed), over conductor 55 and through the winding of magnet 26 to ground, The stepping magnet 26 is thus energized to attract its armature 25 and to operate its pawl 24 leftwardly to pick up the next tooth on the ratchet wheel 23. Then, when the brush arm 42 reaches the stop position wherein the brush 43 thereof is in engagement with the stop segment 55, the brush 48 is in contact with the blank or unenergized portion 82 of the ring 4|, thus causing the aforedescribed energizing circuit for magnet 26 to be held open and the magnet 25 to thus become deenergized to permit its armature 25 to be moved rightwardly by spring 18, so that the pawl 24 will rotate the ratchet wheel 23 one step in a clockwise direction, thus bringing the contactingarms I9 and 2| into contact with the

next contacts

83 and 84, respectively.

Due to the manner in which the contacts 6'! and 83 of the series of contacts are serially connected, the energizing circuit for the stop magnet 54 of the transmitting distributor M will remain energized, thereby permitting brush 42 to continue its rotation. The contacting arm 2| now engages the segment 84, which is indicative of the second character A of the first word of the standard or fixed phrase to be transmitted. A circuit is then completed from battery through shaft 22, over contacting arm 2|, through contact 84, over conductor 85, through contact 86 (now closed), thence over conductor 81 (which extends through the cable 34) to the segment A of the series of segments 21 of the ring 28. Simultaneously with the stepping of the contacting arm 2| into engagement with the contact 84, the gang relay magnet 35 remains energized due to the fact that the contacting portions of contact arms l9 and 2| are sufiiciently wide to span or bridge consecutive contacts so that the circuits for the various relays controlled thereby are maintained during the stepping operation. The contacts H, which include

contacts

61 and 83, are serially connected so that the circuit over the conductor 19 substantially is not broken until the completion of the standard phrase or word of the message; therefore, contact 86 associated with the gang relay is closed at this time. As the brush arm 42 continues in its rotation, it will pass off the stop segment 55 and onto the start segment 56, thus breaking the current in the signaling line as heretofore, and initiating the start or no-current portion of the monopulse code signal as indicated in Fig. 2. However, in this instance, the movement of the brush 43 of brush arm 42 onto the first segment 21, which is the A segment of the ring 28, will cause current to be applied to the signaling line. For this particular signal, the no-current portion of the code signal is very short inasmuch as A is the first segment of the ring. Marking current is applied to the ring 35 of the distributor l4 as soon as the brush 43 engages the segment indicative of the character A, whereupon the afore-described circuit through the segment 84 and over conductor 8'! I is completed through the ring 36, over

conductors

51 and 59, through the contact 15, over the signaling line and through the winding of the selector magnet of the receiving printer 16 to ground, thereby causing the printing of the character A, as described in the afOre-mentioned Patent No. 2,147,075. Since the segment BI is only as long as the combined segments 55 and 5B, the brush 45 will engage the energized portion of ring 39 at the time that the brush 43 engages the contact or segment indicative of the character A on the ring 28, so that the magnet 53 will become energized and will lock up over th afore-described locking circuit, thus applying and maintaining marking current on the signaling line for the duration of the signal from the point marked letter A in Fig. 2 to the stop terminus of the signal. As the brushes 4'! and 48 bridge the lower segment of the ring 4|,current is again applied to the stepping magnet 26 over the aforedescribed circuit therefor. This series of operations is continued for each character of the standard phrase or message. To initiate the transmission of a space signal for word spacing. a circuit is completed through segment 83 which is analogous to the circuits previously described including contacts 19 and 84 and the other se ments of ring 28. 7

After the standard word or phrase has been transmitted, an arrangement has been provided in the present invention for stepping the contacting arms l9 and 2| rapidly back to the position shown in Fig. 1 which is the normal stop position, whereat the contacting arms I9 and 2! rest on blank or unenergized contacts I1 and I8, respectively. Although, for the present description, only one word of the standard phrase has been shown, it is understood that any number of the contacts H and |8 may be assigned to the message, and therefore the remaining contacts I! to be rapidly traversed to the beginning or normal position will be the difference between the number of contacts employed in the message and the total number of contacts in the progress switch. It is, of course, understood that the progress switch would contain suficient contacts to embrace the longest standard phrase desired, and that the conductor 69 would embrace consecutively all the characters and word spaces of the standard phrase instead of only a single word thereof (which, of course, is shown in Fig. 1 only by way of illustration). Therefore, by way of illustration, the remaining contacts H, to the left of the contacts serially connected by the conductor 69, are also serially connected by the conductor 12, so that when the contacting arm l9 engages the first of the latter serially connected contacts ll, namely, 89, a buzzer action is started in magnet 26 to return the contacting arms l9 and 2| to their beginning of line position.

As the contacting arm l9 engages the contact 89, a circuit is completed from battery, through shaft 22, over contacting arm I9, through contact 89, over the conductors 12 and 13, through contact 74, thence through the winding of magnet 26 to ground. The energization of magnet 28 causes its armature 25 to be attracted, and the pawl 24 to be actuated leftwardly to pick up the next tooth of the ratchet wheel 23. At the same time, the armature 25 acts to open the contact 14 to break the circuit just described for stepping magnet 26, which will become de-energized and permit its spring 78 to actuate its armature 25 to operate pawl 24 to cause ratchet wheel 23 to be stepped clockwise one step. Although contact 74 actually closes before pawl 24 completes its rightward travel, the inertia of the moving armature, and the delay in the building up of the magnetic field in magnet 25 are sufficient to permit the completion of this motion and insure reliable step-by-step advancement of the ratchet wheel 23. Thus, the contacting arm I9 is rotated one step so as to engage the contact next succeeding the contact 89 in a clockwise direction, as viewed in Fig. 1, whereupon the circuit for the stepping magnet 25 is again completed over the afore-described circuit including contact I1, conductor 12 and 73, contact I4 (now closed) to again energize magnet 26, whereupon the same action is imparted to the pawl 24 and to the ratchet wheel 23, and the contact I4 is again opened to break the energizing circuit for 25.

This action continues for the remainder of the contacts Ii, so that through this buzzer action the contacting arms I9 and 2| are rapidly rotated back to their normal position shown in Fig. 1.

When the contacting arm I9 leaves those contacts I! which are connected serially by conductor 69, the circuit for the stop magnet 54 of the transmitting distributor I4 is broken thus causing the lock magnet 54 to become de-energized and permitting its armature 53 to fall into the path of the brush arm 42, thereby stopping said brush arm 42 with the brush 43 thereof resting on the stop segment 55, whereupon marking current is again applied to the signaling line through the ring 36 and the conductors 5! and 59 as previously described.

The operation of the circuit hereinbefore given will be exactly the same if the key I5 were to be operated for transmitting the standard phrase identified with the unit I5. Any number of units it and It may be connected through the cables 34 and 9! to accommodate any number of standard phrases or words, and a corresponding number of keys I2 and I5 being provided in a bank of special keys adjacent the keyboard transmitter i I.

Iliodificatz'on Having reference to Fig. 3, there is shown another form of the present invention wherein a single progress switch is provided which controls a plurality of gang relays. relay is provided for each standard phrase or message and is comparable to the units I3 and i 6 in Fig. 1. The progress or step-by-step switch in Fig. 3 comprises an arcuate series of contacts iii! and a corresponding series of contacts I52,

a pair or contacting arms Iii-3 and I04 mounted on a shaft I65. Also mounted on shaft I55 is a stepping ratchet wheel I 55 which cooperates with a pawl I5: pivotally carried on an armature Hit of a stepping magnet I59. The arcuate series of contacts lili includes a pair of dead contacts iii and H2, the remaining contacts I 5i being connected serially.

The arcuate series of contacts 552 include a pair of contacts H3 and M4, the remaining contacts i532 being connected to the contacts of plurality of re ays, four of which a e shown in Fig. 3, and numbered H5, H5, iii, and H8. The contacts of the gang relays M5 to H8 are also connected to conductors which A single gang of the relay I51.

extend through a cable I I9 and terminate at segments of a segmented ring I2I of a brush type distributor indicated generally as I22. I Each of the gang relays II 5I I8 comprises an electromagnet having a plurality of contacts of a minimum number at least one greater than the number of characters and word spaces in the standard phrase represented thereby.

The distributor I22 comprises in addition to the segmented ring I2I, the solid rings I 23, I24, and I25, and the segmented rings I26, and I'2'I. The distributor I22 is also provided with a brush arm I25 carrying brushes I29 to I 35, inclusive. Brushes I29 and -I3I cooperate withrings I2I and respectively, and are connected together by a conductor I88. Brushes I32 and I33 cooperate with the rings I24 and I 26, respectively, and are connected by a conductor I31. Brushes I34 and I35 cooperate with the rings I25 and I21, respectively, and are interconnected by a'conductor I38. The brush arm I28 cooperates with the armature I39 of a stop magnet ML, The ring I2I is provided with a stop segment I42 which is normally connected to battery (as shown), and a start segment I43 to which no current is applied.

' Ring I23 is connected by a conductor I44 to a magnet I 45. Conductor I44 also has a juncture with a conductor I46 which is comparable in purpose to conductor 59 in Fig. 1. Ring I24 is connected to battery (as shown), and the lower portion of. ring I26 is connected by a conductor 54'! to the armature I48 of magnet I45. Armature I48 cooperates through contacts I49 with the winding of magnet I and also with the conductor I 48. Ring I25 is connected by conductors I5I and I52 to the winding of the stepping magnet IIiBof the progress switch. The lower segment of ring I21 is connected by a conductor I53 to the first contact I54 of the series of contacts IBI of the progress switch. The winding of the distributor stop magnet MI is connected at'one end to ground and at the other end'to a conductor I55 which extends to a contact I56 of a control relay I 51, the function of which is to control the restoration of the progress switch to its normal rest position automatically, at the completion of transmission of a standard phrase which has been transmitted under the control of one of the gang relays H5, H6, H1, or II8. Contact I58 of the serially connected contacts I BI is connected by a conductor I59 to a contact I 6| Also connected to the conductor 559 are the relays I62 and I63 for controlling the gang relays I I5 and II 6, respectively. Corresponding relays (notshown) similar to relays I52 and I53 are provided for gang relays II! and H8. Contacts I64, I55, I66, and I6! of'the series of contacts I02 represent end-of-message contacts for the various standard phrases and these contacts are connected through their respective gang relays II5 to II 8 to complete an energizing circuit for control relay I51. For example, if the contact I 64 is the message-end contact for the standard. message or phrase controlled by gang relay I I5, then when the contact arm I04 reaches the contact I 54, a 'circuitwill be completed from battery, through shaft I05, over contact arm I94, through contact I54, then through contact I68 I which will have been closed due to the energization of the magnet I59 of the gang relay I I5 in a manner hereinafter described), over conductors I H and I12, through the winding of relay I5"! to ground, thereby initiating the restoration of the system shown in Fig. 3 to a normal begin- .engagement with the stop segment key and is operated ning-of-message position, in readiness for the transmission of a succeeding standard message In its stop or unoperated condition, the stop magnet II of distributor I22 is unenergized, and hence the armature I39 is spring held in its clockwise position to block the movement of brush arm I28 and to hold the brush I29 in contactual I42. In this positionof brush arm I28, current is applied to the signal line from battery, through stop segment I42, through brush I29, over conductor I36, through brush I3I, over ring I23, over conductors I44 and I46, through contact I13 (which is comparable to contact 86 of the keyboard transmitter disclosed in the afore-mentioned Patent No. 2,173,147), then over the signal line to the receiver I14 (which may be a printer of the type shown in the previously mentioned U. S. Patent No. 2,147,075), thence to ground. Such a condition of the signaling line is the normal, idle condition wherein the condition is said to be marking; that is, with current on the line. In this condition, the magnet I45 remains energized over the afore-described circuit up to and including the conductor I44, from whence the current divides and extends through the winding of the magnet I45 to ground, thereby causing the armature I 48 to be attracted, to close the contact I49, which at this time, as previously mentioned in connection with Fig. 1, has no efiect but its purpose will hereinafter be explained.

Assuming that the following message (which for purpose of comparison will be assumed to be the same as that controlled by the'units I3 in Fig. 1) is to be transmitted, namely, Mr. Fox, wanted on the phone, the operator will operate the keyboard transmitter I15 (of the type shown in U. S. Patent No. 2,173,147), to transmit over the signaling line to the receiver I14 the name "Mr. Fox. Following the operation of the keyboard I15 in this manner, the operator turns to the special bank of keys,

including keys I16, I11, and I18. As described in connection with Fig, 1, the keys I16, I11, and I18 constitute three keys of a bank of keys which may be arranged adjacent to the keyboard device I15. The key I16, in the present embodiment, is identified as the start to initiate the transmission of every standard phrase or message. Each of the other keys I11 and I18 (which are two of a plurality of keys equal in number to the number of gang relays I I to'l I8 which correspond to special or standard phrases to be transmitted) of said bank of keys isallotted to a standard word or phrase; for instance, key I11 may be associated with the standard phrase Wanted on the phone, and key I18 may be identified with the standard phrase Please call your oflice. Thus, key I11 is connected to the gang relay II5 allotted to the phrase "Wanted on the phone, and the operation of this key initiates the transmission of the fixed phrase assigned thereto. With the modification shown'in Fig. 3, it is necessary to operate and release the start key I16 while holding any one of the other keys I11 and I18 down.

The operation of keys I16 and I11 in this man ner will result in the following operations: The operation of key I16 effects the closing of contact I19 to complete an energizing cricuit for the stepping magnet I09 which circuit. as seen from Fig.

3, extends from battery connected to the key I16 through contact I19 and winding of magnet I09 to ground. The efiect of energizing magnet I09 is to attract the armature I08 and to move the pawl I01 leftwardly (as viewed in Fig. 3) to pick up the next tooth on the ratchet wheel I06. Thence, when the key I16 is released by the operator, the current of the stepping magnet I09 is cut off thereby permitting spring II)! to bias the armature I98 clockwise, and to move the pawl I01 to the right to step the ratchet wheel I 05 clockwise to bring the contact arms I03 and I04 on shaft I05 into engagement with contacts I82 and I83, respectively.

This last operation brings contact arm I03 into engagement with contact I82 and a circuit is completed for the start magnet I4I of the distributor I22 from battery, through shaft I05, over contacting arm I53, through contact I82, over conductors I53 and I84, thence through armature I85 and contact I56, over conductor I55, and thence through the Winding of magnet I4I to ground, as a result of which magnet I4! is energized so as to attract its armature I39 and to eirect its disassociation from the brush arm I28, thus permitting the brush arm I28 to rotate through the instrumentality of a friction clutch (not shown) as is customary in such distributing devices. At the same time, a circuit is also completed from battery, through shaft I95, over contact arm I03, through contact I82, over conductor I86 (serially connecting the contacts IOI), then through contact I58, over conductor I59, over conductor I81, thence through the winding of relay I62, through contact I88, over armature I89, then through the winding of gang relay I69 to ground. The gang relay I69 will then. become energized to pull up its armature to close all of its contacts. As the contacting arm I83 is stepped onto the contact I82, the contacting arm I04 is simultaneously stepped onto the contact I83 which, in the present instance, is representative of the character W which is the first character of the first word Wanted of the fixed or standard phrase (selected for this description) to be transmitted. A circuit is now prepared from battery over shaft I85 and the contacting arm I04, through contact I83, over conductor I9I, through contact I92 (now closed), thence over conductor I93 (which extends through cable H9) to the segment W on the ring IZI of the distributor I22. It is to be observed that the operation of the gang relay I I5 is efiected substantially simultaneously with the stepping of the contact arm I 04 onto the segment I83. Therefore, as previously described, the energization of magnet I69 of the gang relay II5 causes all of the contacts associated therewith to close, thus closing at contact I92 the portion of the afore-mentioned circuit which extends from the contact I83. to the segment W on the ring I2 I As the brush arm I28 begins to rotate, the marking condition continues in the signal line until the brush I29 leaves its stop segment I42 and passes onto the blank segment I43, which is commonly known as the start segment. When the brush I29 leaves segment I42, the current in the signaling line is removed and the line is said to be in the spacing or no-current condition. The magnet I45 is thus de-energized and the armature thereof is released, thereby opening contact I49. Also, the selector magnet in the receiving printer I14 is de-energized thus permitting the rotation of its type wheel as described in the afore-mentioned Patent No. 2,147,075. The spacing condition of the signaling line thus continues as the brush arm proceeds to rotate across the start segment I43 and segments I94 of the segmented ring IZI, none of which is energized except the segment W, previously described as being in a prepared circuit. Then, when the brush I29 of the brush arm I28 engages segment W on ring iZI, the afore-menticned circuit, which was prepared through the contact I83 and over the conductor I93, is completed through brush I29, over conductor I 36, through brush I3 I, over distributor ring I23, thence over conductors I44 and I 46, through contact I13, and over the signaling line to the receiving magnet of the receiving printer II I.

-As described in the afore-mcntioned Patent No. 2,147,075, the receiving magnet of the printer will at this time become energized to effcct'printing of the character, at which time the type wheel will have rotated to present the character W thereon to the printing point. Also at this time, the afore-mentioned circuit which was traced through the segment W and over ring I23 will also be completed through the magnet I45 which will be energized to attract its armature I48 and close its contact I t9, thus locking up the magnet I45 over a circuit extending from battery, over ring I24, through brush I32, overconductor I51, thence through brush I33, and over rin I 25, over conductor Ml, through armature I43 and contact I49, thence through the winding of magnet I45 to ground. The magnet I45 is therefore locked up, and as the brush I29 passes off the segment W, thus breaking the circuit through the contacts let and segment marking current will remain on the line through the instrumentality of closed contact I 59 under the control of the magnet I455. The signaling line thus remains in an energized or marking condition as the brush arm I28 continues its rotation back to the stop segment I42 in readiness to initiate another rotation .for the transmission of a succeeding character.

As the brushes I29 and I33 leave segments I 2! and I25, respectively, the brush I33 will. when the brush I22 rests on the stop segment Hi2, rest on the blank segment I95 of ring Iiiii, whereby the current for magnet M5 is no longer obtained through the rings I2 and I25, but only through the stop segment I42 and ring 523. It is understood, of course, that brush i225 must contact segment I42 by the time brush I33 leaves the segment I26.

During the complete rotation of the brush arm I28, not only was the monopulse code signal for the character W transmitted, but also a condition was set up for stepping the progress switch to its next contact preparatory to transmitting the second character A of the first word of the standard phrase. I'hus, as the brush arm traveled approximately two-thirds or threefourths of its cycle of rotation, its brush I35 encountered the lower or energized segment of the ring IZ'I so that a circuit was completed for the energization of stepping magnet I lit from battery, through shaft I65, over contacting arm I53,

conductor I53,

through contact I32, then over through ring I21, then through brush I Y conductor I38, through brush 53%, over ring then over conductors I5I and I52 and through the winding of the magnet I89 to ground. The stepping magnet its is thus energized to attract its armature Hi8 and to operate its pawl It? leftwardly to pick up the next tooth on the ratchet wheel m5. Thus, when the brush arm I28 reachesthe stop position wherein the brush I29 thereof is in engagement with the stop segment I42, the brush I35 is in contact with the blank or unenergized portion I96 of the ring I21, thus causing the afore-described energizing circuit for magnet I09 to be held open and the magnet I09 to thus become de-energized to permit its armature I38 to be moved rightwardly by spring I8I, so that the pawl III! will rotate the ratchet wheel Iilfi, one step in a clockwise direction, thus bringing the contacting arms I03 and IM into contact with the next contacts I91 and I98, respectively.

Due to the manner in which the contacts IIlI are serially connected, the energizing circuit for the stop magnet MI of the transmitting distributor I22 will remain energized, thereby permitting the brushes of the distributor to continue their rotation. The contacting arm I64 now engages the segment 198 which is indicative of the second character A of the first word of the standard phrase to be transmitted. A circuit is then completed from battery through shaft I35, over contacting arm I I34, through contact I98, over conductor IE9, through contact 22 (now closed), thence over conductor 292 (which extends through the cable III!) to the segment A of the series of segments I94 of the ring I2 I. The gang relay I69 remains locked up over the aforementioned circuit extending from battery through shaft I05, contact arn I63, conductor conductors I59 and I8}, winding of magnet I552, contact I88 and armature Hit, and winding of the relay I69 to ground. The transmission of the monopuise code signal identified with the character A will be efiected in the same man- 1 nor as was described in the embodiment as exemplified in 1. As the brushes I34 and I35 encounter the lower portion of the ring IZl, current is again applied to the stepping magnet 39 over the aforedescribed circuit therefor. This series of operations is continued for each character and space of the standard phrase or message.

After the standard word or phrase has been transmitted, the contacting arms I93 and I94 are stepped rapidly back to the position shown in Fig. 2, which is the normal stop position. At the conclusion of each standard message, there is a contact; for example contact Ilia identified with the present described message, which, when contacted by the arm I94 will complete a circuit for the energization of the control relay I57, from battery, over arm I04, through contact I64, through contact I68 (now closed), over conductor III and I72, through the winding of relay I5! to ground. The energization of magnet or relay I57 will cause the armatures I85 and 292 thereof to be attracted, thus closing contacts 295 and 5|, respectively. Relay I5 will become locked up over a circuit from ground, through the winding of relay IS'E, through contact 285, over armature I85, .over conductors I34 and I53, contact Iii l, over conductor I85, through contacting I93 (as it traverses the serially connected contacts Ifii), thence to battery. Another stepping circuit for magnet I159 will be completed battery, through contact arm over contacts MI and conductor I85, contact I58, over conduc tor Hi9, through contact I 5| over armature 2M, thence over conductor 2%, over armature 295, over conductor I52, and through the winding of magnet I95 to ground. Magnet I BE will become energized and pull up its armature W8 to advance the pawl I to pick up another tooth on the ratchet I06. However, by the same action,

ing or buzzing action will continue until the contact arms 593 and I04 have reached their respec- -tive dead contacts III and H3, whereupon the progress switch is thereby restored to its normal position for the initiation of transmission of a new standard phrase upon the depression of one of the contact keys I11, I18, and start key I35. When contact III is thus reached, the magnet IE! will become de-energized because of the breaking of the locking circuit therefor, inasmuch as arm I93 will not carry current because contacts III and H2 are dead contacts.

The contact I64, which is the message-end contact identified with the previously described message group of contacts controlled by the gang relay IE5 and acts through the contact I58 of the gang relay [I5 to control the relay I51, may for some longer message be a contact for controlling a specific character oi that message. For example, contact I64, besides representing the message-end contact of a standard message such as wanted on the phone, may be also a character of another message such a please call your oflice. In such event, the contact I68 is connected directly to a contact of another gang relay which controls the last-mentioned message; that is, gang relay IIB. Accordingly, for the lastmentioned message, the message-end contact might be such as is indicated I65 in Fig. 3, which is connected to a contact 201 in the gang relay lit and to the winding of the control relay I51. This contact indicated 291 may also be connected to a contact 208 in gang relay H1, and thus the contact I66 may represent not only a messageend signal, but may also represent a character; P

in the message controlled by the gang relay II'I, represented by contact 208.

Although the present invention has been disclosed in connection with certain specific embodiments thereof, it is understood that such embodiment are merely illustrative and not restrictive and that all forms coming within the scope of equivalency of the appended claims are intended to be covered by the invention.

What is claimed is: 1

l.' In a signal transmission system, a start-stop rotary distributor comprising a plurality of segments and an itinerant seeker operable thereover, a step-by-step switch, a plural contact relay device, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and a contact in said relay device in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, means eiiective upon the traversal of said seeker over the segment of a prepared circuit to establish the definitive impulse of said code signal irrespective of the condition of the segments further traversed, and means under control of said distributor for stepping said switch sequentially to produce through the instrumentality of said relay a predetermined message.

2. In a signal transmission system, a start-stop rotary distributor comprising a plurality of segments and an itinerant seeker operable thereover, a step-by-step switch, a plural contact relay device, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and a contact in said relay device in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, means effective upon the traversal of said seeker over the segment of a prepared circuit to establish the definitive impulse of said code signal irrespective of the condition of the segments further traversed, means under control of said distributor for stepping said switch sequentially to produce through the instrumentality of said relay a predetermined message, and means effective automatically following the transmission of said predetermined message to condition said progress switch for reoperation.

3. In a signal transmission system, a start-stop distributor comprising a plurality of segments and an itinerant seeker operable thereover, a progress switch, a plural contact relay device, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and a contact in said relay device in predetermined manner, means for preparing said circuits individually under the control of said switch, mean for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, electromagnetic means, means effective upon the traversal of said seeker over the segment of a prepared circuit to operate said electromagnetic mean to establish the definitive impulse of said code signal irrespective of the condition of the segments further traversed, means under control of said distributor for stepping said switch sequentially to produce through the instrumentality of said relay a predetermined message, and means effective automatically following the transmission of aid predetermined message to condition said progress switch for reoperation.

4. In a signal transmission system, a start-stop distributor comprising a plurality of segments and an itinerant seeker operable thereover, a progress switch, a plural contact relay device, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and a contact in said relay device in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, electromagnetic means, means effective upon the traversal of said seeker over the segment of a prepared circuit to operate said electromagnetic means to establish the definitive impulse of said code signal irrespective of the condition of the segments further traversed, and means under control of said distributor for stepping said switch sequentially to produce-through the instrumentality of said relay a predetermined message.

5. In a signaling system, a keyboard transmitter having a switch mechanism for operating a transmitting contact in a signal line to generate monopulse isochronous code signals, an auxiliary transmitting means exercising dual control over said signal line comprising means effective under certain operating conditions to effectuate a first predetermined control of said signal line and means effective under other operating conditions to eilectuate a definitive control of said signal line to consummate the generation of monopulse isochronous code signals, and means for controlling the transmission of signals by said auxiliary transmitting means, whereby aid transmission is effective through said transmitting contact.

6. In a signaling system, a keyboard transmitter having a switch mechanism for operating a transmitting contact in a signal line to generate monopulse isochronous code signals, an auxiliary transmitting means exercising dual control over said signal line comprising means efiective under certain operating conditions to edectuate a first predetermined control of said signal line to produce the character selecting impulse of a monopulse isochronous code signal and means eifective under other operating conditions to eirectuate a further control of said signal line to establish the definitive impulse of said code signal, and means for controlling the transmission of signals by said auxiliary transmitting means, whereby said transmission is effective through said transmitting contact.

7. In a signaling system, a signal line, a transmitting means exercising dual control over said signal line comprising means eifective under certain operating conditions to effectuate a first predetermined control of said signal line to produce the character selecting impulse of a monopulse isochronous code signal and means effective under other operating conditions'to efi'ectuate a further control of said signal line to establish the definitive impulse of said code signal, a progress switch, a plural of circuits each switch and said ing a contact of said relay device in accordance with a predetermined message to be transmitted, means for preparing said circuits individually under the control of said switch, means for controlling the establishment of said circuits to effectuate the transmission of mono-pulse code signals thereover, and means under the control of said transmitting means for stepping said switch sequentially to produce said message.

8. In a signal transmission system, a startstop distributor comprising a plurality of segments and an itinerant seeker operable thereover, a progress switch, a plurality of multiplecontact relay devices, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and contacts in one or more of said relay devices in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, electromagnetic means, means eiTective upon the traversal. of said seeker over the segment of a prepared circuit to operate said electromagnetic means to establish the definitive impulse of said code signal irrespective of the condition of the segments further traversed, and means under control of said distributor for stepping said switch sequentially to produce through the instrumentality of an operated one of said relays a predetermined message.

9. In a signal transmission system, a startstop distributor comprising a plurality of segments and an itinerant seeker operable thereover, a progress switch, a plurality of multiplecontact relay devices, a plurality of circuits each contact relay device, a plurality connected between said progress transmitting means and includ-- stop rotary distributor corresponding with one of said segments and embracing a terminal of said switch and contacts in one or more of said relay devices in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, electromagnetic means, means effective upon the traversal of said seeker over the segment of a prepared circuit to operate said electromagnetic means to establish the definitive impulse'of said code signal irrespective of the condition of the segments further traversed, means under control of said distributor for stepping said switch sequentially to produce through the instrumentality of an operated one of said relays a predetermined message, and means efiective automatically following the transmission of said predetermined message to condition said progress switch for reoperation. I

0. In a signal transmission system, a startstop rotary distributor comprising a plurality of segments and an itinerant seeker operable thereover, a single step-by-step switch, a plurality of multiple-contact relay devices, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and contacts in one or more of said'relay devices in predetermined manner, means.- for, preparing said circuits individually under the control of said switch, means for initiating the rotation of said seeker to produce the character selecting impulse of a monopulse isochronous code signal, means efiective uponthe traversal of said seeker over the segment of a prepared circuit to establish thedefinitive impulse of said code signal irrespective of the condition ofthe segments further traversed, and means under' control of said distributor for stepping said switch sequentially to produce through the instrumentality of an operated one of sage. i 1

11. In a signal transmission system, a startcomprising a plurality of segments and an itinerant seeker operable therecver, a single. step-by-step switch, a plurality of multiple-contact relay devices, a plurality of circuits each corresponding with one of said segments and embracing a terminal of said switch and contacts inone or more of said relay devices in predetermined manner, means for preparing said circuits individually under the control of said switch, means for initiatingthe rotation of 1 said seeker to produce the character selecting impulse of. a monopulse isochronous code signal, means effective upon the traversal of said seeker over the segment of a prepared circuit to estab lish the definitive impulse of said code signal irrespective of th condition of the segments further traversed, means under control of said distributo-r for stepping said switch sequentially to produce through the instrumentality of an operated one of said relays a predetermined message, and means effective automatically following the transmission of said predetermined message to condition said progress switch for reoperation.

12. In a telegraph system, a primary transmitting device for transmitting messages of changeable character, said device comprising a, single normally closed line contact and means for generating monopulse isochronous code signals, an auxiliary transmitting device for transmittinga fixed message, said auxiliary device comprising a progress switch and automatic means for definsaid relays a predetermined mesing monopulse isochronous code signals under the control of said switch, and means for automatically restoring said auxiliary transmitting device to normal atthe conclusion of transmission of a fixed message.

13. In a telegraph system, a primary transmitting device, a series of keys for controlling the transmission by said device of messages of a changeable nature in accordance with the keys operated, said device comprising a single normally closed line contact and means for generating a monopulse isochronous code signal upon the actuation of each key, an auxiliary transmitting device for transmitting a fixed message, a series of message keys one allotted to each fixed message, said auxiliary device comprising a progress switch and automatic means responsive to each operation of a message key for defining monopulse isochronous code signals under the control of said switch.

14. In a telegraph system, a primary transmitting device, a series of keys for controlling the transmission by said device of messages of a changeable nature in accordance with the keys operated, said device comprising a single normally closed line contact and means for generating a monopulse isochronous code signal upon the actuation of each key, an auxiliary transmitting device for transmitting a fixed message, a series of messagexkeys one allotted to each fixed message, said auxiliary device comprising a progress switch and automatic means responsive to each operation of a message key for defining monopulse isochronous code signals under the control of said switch, and means for automatically re-.

storing said auxiliary transmitting device to normal at the conclusion of transmission of a fixed message.

l5. Ina telegraph system, a primary transmitting device, a series of keys for controlling the transmission by said device of messages of a changeable nature in accordance with the keys operated, said device comprising a single normally closed line contact and means for generating a monopulse isochronous code signal upon the actuation of each key, an auxiliary transmitting device for transmitting a fixed message, said auxiliary device comprising a progress switch, a plurality of multiple-contact relay devices, and automatic means for defining monopulse isochronous code signals under the joint control of said switch and said relays. 16. In a telegraph system, a primary transmitting device, a series of keys for controlling the transmission by said device of messages of a changeable nature in accordance with the keys operated, said device comprising a single normally closed line contact and means for generatin'g a monopulse isochronous code signal upon the actuation of each key, an auxiliary transmitting device for transmitting a fixed message, said auxiliary device comprising a progress switch, a

plurality of multiple-contact relay devices, automatic means for defining monopulse isochronous code signals under the joint control of said switch and said relays, and means for automatically restoring said auxiliary transmitting device to normal at the completion of transmission of a fixed message.

17. In a telegraph system, a line conductor, a printing telegraph receiver connected to said line conductor, a primary transmitting device for generating signal impulses for application to said line conductor to operate said receiver according to a variable message, an auxiliary transmitter arranged to generate the same type of signal impulses generated by said primary transmittin devices, and means in said auxiliary transmitter for determining the impulses of any one of a plurality of fixed messages to be transmitted over said line conductor and recorded on said receiver.

18. In a telegraph system, a line conductor, a printing telegraph receiver connected to said line conductor, a primary transmitting device for generating signal impulses for application to said line conductor to operate said receiver according to a variable message, an auxiliary transmitter arranged to generate the same type of signal impulses generated by said primary transmitting devices, and means selectively controlled by an operator for determining the impulses of any one of aplurality of fixed messages to be transmitted by said auxiliary transmitter over said line and recorded on said receiver.

19. In a telegraph system, a line conductor, a printing telegraph receiver connected to said line conductor, a primary transmitting device for generating signal impulses for application to said line conductor to operate said receiver according to a variable message, an auxiliary transmitter arranged to generate the same type of signal impulses generated by said primary transmitting devices, and means selectively controlled by an operator following the operation of the primary transmitter for determining the impulses'of any one of a plurality of fixed messages to be transmitted by said auxiliary transmitter over said line and recorded on said receiver following the recording thereby of the variable message.

20. In a telegraph system, a line conductor, a printing telegraph receiver connected to said line conductor, a primary transmitting device for generating signal impulses for application to said line conductor to operate said receiver according to a variable message, an auxiliary transmitter arranged to generate the same type of signal impulses generated by said primary transmitting devices, means individually allocated to fixed messages,'and means selectively controlled by an operator to operate said means whereby impulses identifying said particular fixed message will be transmitted by said auxiliary transmitter over said line to effect operation of said receiver.

' ALBERT H. REIBER.