US1628696A - Pbogeam-seiectik g ciecuits - Google Patents

Description

` l 27. May 17. 9 J, F.1ooMEY PROGRAM SELECTING CIRCUITS Fil'ed Dc. rl0, 1923 /NVENTDR ef. l? 770mg/ A TTORNE V.

Patented May i7, i927.

ldizt unire stares earner JOHN F. TOOMEY, 0F NIE-"iii" YORK, N. Y., ASSGNGR TO AMERCAN TLEPHNE AND TELEGRAPH CGMPANY, A CQRPORATON 0F NEW YORK.

PROGRAM-SELECTNG CIRCUITS.

Application filed December 10,V 1923. Serial No. 679,753.

lhis invention relates to transmission sys tems for sending); programs over wires, and more particularly to :rraugements tor the selection ot programs tor such systems.

Vhere wire lines, such as ordinary telephone lines, tor example. are used ier the transmission ot entertainment programs, such as news, lectures, concerts and the like, is desirable that some arrangement be lnovided whereby the subscriber may automatically select the particular' program which he desires to hear. ln accordance with the present invention, it is proposed to accomplish this result by providingl a selective switch at the central other; which may be directively controlled by an operator to connect the terminals of the subscribefs line to the terminals of any one ot a number ot trunks each leading to a different program. `When the subscriber desires a particular program, he can then call up over his telephone .line in the usual manner and inform the operator of the program which he desires, and the operator can then connect that program to the line.

By the use of a directively controlled seleotive switch for selecting a program, it becomes immaterial whether the program be transmitted at voice frequencies or carrier frequencies, and it also becomes immaterial whether the several programs be transmitted at the same `frequency or whether different carrier frequencies are used for diilerent programs. By permitting the directive switch to be controlled by the operator rat-her than the subscriber, circuit complications due to dialing over the subscribers line are eliminated.

The invention will now be more fully understood from the following description when read in connection with the accompanying drawing, the figure ot which illustrates a circut arrangement whereby a directive switch may be used to select programs.

Referringto the drawing, L designates an ordinary telephone transmission line terminating in the usual subscribers set S at one end and terminating at the central oiiice in the multiple jacks J and J. Normally the telephone line L is connected over the contacts of a cut-ott' relay CO to a transformer 20, whereby the line is associated with conductors l1 leading` to a directive switch Dit tor connecting the line with the desired program. rihe line relay LR has its windings connected on either side of the condenser 2l intermediate between the .two 'halves oi the secondary winding oit the transformer 20. The cutoff relay CO is so arranged that when it is operated the line L is disconnected from the transformer 2O and hence from the line relay LR, and is connected directly to the tipand ring` terminals of themultiple jacks J and J.

ln order that the line may be used for program transmission during such time as it is not being' used for ordinary telephone purposes, a program receiver such as the loud speaker LS is provided at the subscribers station, said receiving device beine; bridged across the line through the back Contact of the switcbhook l() and through the contactof a relay 23. The relay 23 is so arranged that it will be operated to connect the loud speaker to the line upon the momentary actuation of the upper contact of the non-locle` ing key K. On the other hand,r the relay 23 is so arranged that it will be released to dis connect the loud speaker upon takingthe receiver from the switchhook to mak-c a call or upon the operator insertingl a plug into one of the multiple jacks to call the subscriber. It may also be released by the subscriber when he no longer desires to hear a program by momentarily opening the lower contact of the lrey K.

At the central otiice the wipers 25 and 26 of the directive .switch` DB are arranged to connect the conductors 1l to any one of a plurality of trunlrsA, B, C, D, E, etc.. leading' to different voice frequency programs.

In order to operate the switch DR a stepand 28, as will be described hereinafter. The

so arranged that it will be oper switch is l by step under the control er 'the ated step dial and will be released and restored to normal by the mon'ientary operation ot the release magnet.

Further details et the apparatus will he Clear from the desoription ot the operation which is as tollon's: lVhen the line L is not in use for telephonie purposes and the subscriber desires to hear a program, such, for example, as the program C, the subseriber will remove. his receiver trom the switch-- hook 10, thereby operating' the line relay LR to eal'l the attention ot the operator at the central otiiee. The operator ,inserts a plrnev in the answering` jaeli in the usual manner, thereby operating the ente-.l relay C() and connecting the line L to the jack J. ll pon ascertaining the program desired by the sub-- seriber, the operator n'ill Withdraw the plug; et her Cord Circuit from the answer farle. J, thereby releasing` the ent-olf relay C() and again connecting the line L to the non duetors ll through the transtormer Q0. The operator then inserts the ,A P in the jack J and operates the dial L, in the same manner as is Customary in the oiieration ot machine switching dials. l? or efiainple, the dial may have each ot holes provided with a letter corresponding to each o't the programs. The operator, in the case assumed, Will insert her finger .in the hole marked C and rotate the dial until her finger comes against the stop, when the dial is released. As soon as the dial begins to re tate, the ott-normal Contact 29 ot the dial is Closed and remains elosed until the dial is restored to normal atter being released. The closing,Y of the oil-norma-l Contact oompletes a circuit trom ground, over the eontaets 29 and 32, through the Contacts of the plugr P and jael; J and through the Winding ot slow release relay 27 to battery. Relay 27 is at onre energized an d is sulteiemtly slow in releasingr its armature so that its armature Will not be released through momentary interruptions of the eireuit et the dial let, due to the dialing` operation.

Relay 27 at is itront Contact Completes a circuit over the right-hand haelt; contant ot relay 2S 'tor the release magnet RM. Relay 27 at the same time elosesa circuit Vfor the slow operating relay so that a'tter a moment the reli i 28 opens the Circuit ot the re lease. ma gnat RM'. The momentary euer-gim-r tion ot the release magnet RM. lunvever. causes the directive siviteh DR to be released and restored to normal. betere any impluf-ies are beine,` transmitted 'trein the dial 24, the operations Whieh have just been described taking plaee while the dial is being advaneed. As is Well known, the impulses sent trom the dial ar transmitted after it is released. Relay 28,. upon being energized, Closes a eirenit trom battery, over its lett-hand it'ront contant, through the winding oit the stepping' magnet SM, over the eontaets ol the jaeli 2.; and have been advanced to the r-'rutaets ronneeting the eonduetrns ll to the dernreifl pug'ograrn, which in the ease assumed, i the program (l. Upon the dial being re store to normal, the eti-normall eonlaet E35) is opened and Consequently. the slow acting; relay QT is released. This rel'aj,v in t; 1 opens the circuit of the relay n iii) .vhieh Closes a circuit of the release magnet RM at one point, hut the eireuit opt said magnet has been preifiously opened by the Contact of the relay 2T, so that the release magnet is not energia-:re at this time.

In the meantime, the subscriber hangs up his receiver' and momentarily operates the non-looking key K to close its Contact 33. This completes a eireuit from battery through the right-hand Winding of the line relay LR, over the lower back Contact et the eut-ott relay CO, over thev ring-3r conductor ot the line L, over the baol Contact of the sWitehhook l0, over the normally Closed contaet 3l of the key K, over the momentarily closed.y Contact of said key, through the winding;` ot the relay 23, over the tip oonduetor oft' the line L, over the upper back Contact of the eut-ott relay C() and through the lett-hand winding ot the line relay LR to ground. Owing to the high resistance ot the relay 23, the line relay LR is not aetu ated by the Circuit above traced, but the relay 23 is operated and. at its inner front eon- W' taet completes a looking circuit independent of the eontaet $553 of' the key K. At its outer tronteontaet relay 2? bridges the loud speaker LS aeross the line so that the sul seriber may non' listen to the program transmitted over the eondrmtors l14 and thun I, the transformer 20 to the line.

It a Call should come in ,for the subseri ber while the eirouit is being;- used 'tor reception et a program, the operator inserts a plug ot' her cord eireuit in one of the multiple jaelis, tor example, the jack; J", thereby energizing the eut-ott relay CO. The eut-olli relay shifts the connections ot the line L from the conduetors l1 to the multiple jacks, to which the oord eireuit is Connected. This momen-- tarily interrupts the circuit previously traced for the relay 3, which releases and opens its looking` Circuit before a new eireui't is established for said relay to the battery associated with the cord circuit. Accordingly, the relay `23 disconnects the loud scriber hangs up his receiver and when the `he merely removes the receiver from the switchhook l0. lhis opens the locking circuit of' thc relay 23 and causes said relay to be released and disconnect the loud speaker LS fromthe line in themanner already described. At its upper contact the switchhook l completes a low resistance circuit through the line relay LR, as already described. Upon observing the glowing ot the line lamp, the operator inserts a plug' in the jack J, thereby operating the cut-ofi relay CO to disconnect the line L from the conductors 1l and connect it to the `multiple jacks. The telephone connection is then completed in the usual manner and the conversation proceeds. At the end of the conversation the subscriber hangs up his receiver and upon the connection being taken down, the subscriber can again listen to the program by actuating the `key K to close the contact 33, as already described.

When the subscriber desires to discontinue the program connection he operates the key K to niomentarily open the contact 31. This releases and unlocks the relay 23, thereby disconnecting the loud speaker LS from the subscribers line. The setting of the switch DR is not disturbed by this operation. It the subscriber should thereafter desire to change the program, he does so by calling up the operator, as already described, whereupon the operator will plug the dial 24 into the jack J and dial a new program. A s already described, the initial operation ot the dial causes the release magnet RM to restore the switch DR to normal so that in response to the pulses transmitted, it will `lhat is kclaimed is:

hln a wired program system, a Subscribers telephone line terminating in a subscriberis telephone apparatus at the `subscribers station, switching means at the central office whereby a connection may be established between said subscribers line and f for establishing a connection between saidy line and any desired trunk, and controlling means at the central oiiice whereby the operator may control the operation of said selective switching means. i

in a wired programsystem, a subscril'iefs telephone .line tern'iiuating in a subscribers telephone apparatus at the subscribers station, switching means at the central oilice whereby a connection may ,be established between said subscribers line and another subscribers line, a pluralityV of trunksat the central oiiice upon which programs may be impressed, a directive switch independent of said iirst mentioned switching means at the centraloiiice .for establishing a connection between said line and any desired trunk, and controlling means at the central oiiice whereby the operator may control the operation of said directive Switch to select a program. l

ln a wired program system, a subscribers telephone line terminating in a subscribers telephone apparatus at the subscribers station, switching means at the central oiice whereby a connection may be established between said subscribers line and another subscrihes line, a plurality of trunks at the central ofice upon which programs may be impressed, a directive switch independent ofA said first mentioned switching' means at the central office for establishing a connection between said line and any desired trunk, controlling means at the central oiiice whereby the operator may control the operation ci said directive switch to select a program, and means for restoring said switch to normal at the beginning of its operation to select a program.

li. In a wired program system, a subseriberls telephone line terminating in a subscriberis telephone apparatus at the subscribers station, switching means at the central ofce whereby a connection may be established between said subscribers line and another subscribei"s line, a plurality of, trunks at the vcentral otiice upon which programs may be impressed, a step-by-step switch independent of said rstmentioned switching means at the central otice for switching said subscribers line to a desired trunk, and means at the central oiiice whereby the operator may control said switch.

ilo

lill) l besaen 5. In a wired program system, a subscitiberrs telephone line terminating in a subscriber-7s telephone apparatus atthe subscxibeins station, switching ymeans at the central ofiicelwlmreby a connection may be' cst-ablished between said subscribers line and another subscribcns line, a plurality of trunks. at the cent rel. .oiiice upon which prof `seribers telephone apparatus atV the subscniberisfetation, switching means :it the central office whereby a connection may be established bet-Ween said'subscribers line and another subscriber-7s line, a plurality of Vtrunksaty the central otlice upon which programs maylbe impressed7 an impulse-oper ated. selecting switch independent of said first mentioned switching means at the central office vand an impulse sender. at thel central oilice for transmittingimpulses to said switch to operate the same to establish a connection between said subscribers line and any desi red trunk.

7. In a. wired program system, a subscribe1"s telephone line terminating in a subscribcis telephone apparatus atthe sub scribers station, switching means-nt the central officewhereby a connection may be' established between said subscribers line and. another .snbscribens line, a plurality oi trunks at the central oltice uponA which programs may be impressed, an impulse-operated selecting switch independent ofsaid first mentioned switching means at the central otiice, an impulse sender at the central ofiice for transmitting impulses to seid switch to operate the same to establish e connection between said subscribers line and any desired trunk, and means' to yrestore said switch -to normal at the beginning of its operation to establish x11-connection to another trunk.

In testinony whereof, I `have signed rmy name to this specification this '7th vdey of December, 1923.

JOHN F. TOOMEY.

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