US1635155A - Radio service metering system - Google Patents

Description

July 5 1927- E. CLEMENT RADIO sERv'Ic E METERING SYS TE M 5 Shecs-Sheet 1 OrizinalFiled Dec. 6. 1924 Q is E. CLEMENT RADIO SERVICE METERING SYSTEM Original Filed Dec. 6, 1924 5 SheetsShee1': 2.

Jul 5, 1927.

E. E. CLEMENT RADIO SERVICE METVERYI'NGISESTEM Original Filed Dec. 6. 1924 5 Sheets-Sheet 3 1,535,155 July 1927' E. E. CLEMENT RADIG SERVICE METERING SYSTEM Original Filed Dec 5. 1924 5 Sheets-Sheet 4 1,635,155 July 1927" E. E. CLEMENT RADIO SERVICE METERING SYSTEM v Original Filed Dec. 6. 1924 5 Sheets-Sheet 5 'TELEP/ION CENT)? EXCl/IN E Patented July 5, 1927.

UNITED STATE PATENT OFFICE,

EDWARD E. CLEMENT, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO EDWARD F, COLLADAY, 013 WASHINGTON, DISTRICT OF COLUMBIA.

' RADIO SERVICE METERING SYSTEM.

Original application filed December 6, 1924, Serial No. 754,406. Divided and this application filed August 1, 1925.

This application is a division-of my 00- systems of radio broadcast distribution, and

has for its object to organize such a system so that programs may be originated, relayed, and distributed over a wide area, in a systematic and orderly manner'so that ultimate receiving stations may be controlled and operated as subscribers stations and the programs distributed may be confined to said subscribers stations and not'b'e available for outside receiving stations not forming a part of the system; so that subscriber's may select different programs or difi'erent'items from different programs as time of rendition proceeds; so that subscribers may obtain any item produced and distributed from any part of the system to any other part of the system and within the range of their selective apparatus: so that while the subscribers may' get the full benefit of amplification and the use of vacuum tubes in receiving and,

amplifying, yet their stations will be tubeless, thatis to say, all the tubes pertaining to subscribers receiving apparatus shall be located at central points, which may be also the final distributing points through which the programs or signals are given to the subscribers; so that all reception by the subscriber of programs or rogram items selccted by him, shall he (li erentially metered according to the value fixed'upon them by the broadcasting authorities, and automatically recorded at the rates sodetermined; so that a subscriber may have nothing at his station but standard telephone apparatus, connected and operating in conjunction with telephone line circuits. but capable of operating a loud speaker when desired; and finally so that the entire control, supervision, metering, currentsupply, installation and maintenance of subscribers; instruments will be from organized central stations provided with expert operators.

I attain these and other objectsjvhioh will sufiiciently appear hereinafter by connecting all the subscribersl stations in groups to localized central ofiices or exchanges, providing such exchanges with receiving instru- 'ments which may be of any suitable type, such as those described in my prior copending application, Serial No. 746,357, filed October 28, 1924; providing line circuits en- -Serial No. 47,550.

control, supervise, etc.

This invention is applicable to manual, automatic or so-called semi-automatic or automanual telephone-systems, as will sufficiently appear hereinafter. The main underlying principle involved is that of relaying atthe local central stations from one or more receiving instruments to a plurality.

0t subscribers lines by means of individual line tubes or valves, so that each line may have its own self contained.- receiving unit,

needing only excitation by the central ofiice relay transmitter, combined with means for metering the service rendered the subscriber. The method I have found most satisfao tory in practice is to include'one stage of audio amplification in each central ofiice relay set or transmitter, the line tubes constituting a second stage, Current carrying capacity and power of the line tubes may be varied within wide limits, affording any amount of energy for transmission and any class of service that is desired. It the exciting circuits connected to any one bus at one time are too many, the bu'sses may be banked by means of tubes in parallel as well understood in the art. In this case, each central ofiice receiver supplying a bus would preferably have a detector tube connected .through a transformer toa plurality of audio amplifier-tubes in parallel, constituting a multipled first stage, the plate circuits of which would be connected to the bus through a suitable transformer.

Regulation of the current flow from the B i or plate batteryLthrough each bus during program transmission may be obtained by means known in the art and usually manipulated by an operator at a transmitting station.

Some modifications can be made in theiarrangement, and many modifications-in the detail of circuit and design, but I feel the principle as stated to be novel in its application and original with myself, and I shall claim the same accordingly.

My invention is lllustrated 1n the accompanylng dr-awlngs, 1n which:

Figs. 1 and 2 indicate, diagrammatically,

the telephone exchange portion, and broad- .cast distributing portion, respectively, of

cast distribution embodying the invention.

Fig. 6 is a diagram of a trunking arrangement for extending a subscribers line circuit outside the local central station.

Fig. 7 is a schematic diagramshowing the general arrangement for distribution of a broadcast program through an amplifier circuit-common to a plurality oflines and second stage amplifier tubes and circuits individual to the subscriberis line.

Referring to .the drawings in detail and first to Fig. 1, this shows the essentia circuits of an ordinary telephone exchange system in which A is a subscribers station connected by line wires 69-70 to the central station C where they terminate on multiple jacks J. Similarly, the multiple jacks J form the line terminals of another substation not shown. These 'acks, are arranged to be interconnecte throu h the usual answering and calling plugs -P with the usual line rela y 'L, line amp forming the terminals of the usual common battery cord circuit shown. oflice terminals of""each lineare rovidid and cut off relay L Whereservice-ls to bemetered a recording meter M is also individually associated withthe line. Thus, the circuit arrangement here shown is that of the standard multipleswitchboard, common battery, telephone exchange system, and as such is well understood in the art further detailed description thereof will be here de- .ferred and brought out later inthe description of operation.- In addition to the usual line terminal multiples 1,2 and 3, representing multiples of the tip, ring and test or cut-01f circuits, respectively, I provide a fourth conductor 4 leading from a contact on the line relay along with the multiple conductors 1, 2 and 3 to the broadcast distributing system diagrammed in Fig. 2.

Fig. 2 shows the broadcast distributing system of which the portion to the left of the dotted line is situated at the central ofiice and connected with the subscribers telephone line terminal apparatus of the telephone central C (Fig. 1) through conductors 1, 2, 3 and 4, while the portion to the The central right of the dotted line in Fig. 2 is situated at the subscribers substation and connected with the subscribers telephone substation apparatus A (Fig. 1) through the multiple conductors 5 and 6. In Fig. 2 the subscribers line multiples 1-2 terminate in contacts 7--8 of an automatic selector switch.

9. This switch is of a type well understood in the automatic telephone art in which movable contacts or wlpers suchl'as 7 and 8 are carried on a shaft 10 biased in a given nortion of the release magnet effecting the.

tripping of the dog 14 through an extension 16 on its armature 17 pivoted at 18. To hold up the armature extension 16 until the switch has released, a trip detent 19'is-provided which is pivoted at 20 and arranged to be held normally out of engagement with the hook 21 on the armature 17 by a cam 22 on the switch shaft which permits the detent l9. to move into operative relation with the hook 21 whenever the switch is in off-normal position. Mounted on the switch'shaft 10 are other pairs of wipers 232t, 2526, and

27-28. The switch 9 is provided with a contact bank containing rows of contacts 30, 31-, 32 and -33 arranged to be engaged by the'switch wipers 78, 23-24 etc, successively in the direction indicated by the adjacent arrow, 'it being understood that while the drawing, which is purely diagrammatic shows the contacts arranged in a straight line they are in practice arranged in a circle concentric with the switch shaft so as to permit the switch arms to sweep across them in the rotation of the shaft. While only three vertical rows of contacts are here shown it is to be understood that they may be more or less in number and that in any case the first few vertical rows of contacts are left blank or disconnected, for example, in the present case the first five, leaving the sixth vertical row of contacts the first ones that areconnected with the operating circuits sothat the switch must make five steps before elfectin any CiIfZlUt connections, after which the wipers will be moved successively to the sixth. seventh and eighth vertical rows. The purpose of progviding this lost motion or blank steps will grid and filament of the tube 37, while ill) the wipers 26 and 28 form the terminus of the wiper 27 is connected to the multiple test wire 3, leading into Fig. 1. The horizontal row of-contacts 30 are connected as multiple pairs, the upper and. lower members being connected respectively to the remote terminals of the coils'38 and 39 of the repeating coil 36 through the conductors 40 and 41, the .conductor 41 connecting with the coil 39 througha line supply relay 42, shunting resistance 43 and conductor 44. The adjacent'terminals of the coils 38 and39 are connected to the plus and minus side of the exchange common battery B through conductors 45 and 46, and bus conductors 47 and 49, respectively. 6 In the horizontal row of contacts 31, the sixth, seventh and eighth pairs are connected individually to the batteries B, B and B respectively. In the horizontal row of contacts 32, the sixth, sevcnth and eighth pairs are connected, respectively, to the diiierent program transmitting sets P, P, and P ,'the lower contacts of the sixth, seventh and eighth pairs being connected respectively to the bus wires of filament batteries F F and F respectively. In the horizontal row of contacts 33 the upper members of each pair are connected in multiple to the conductorv 49 which supplies battery current for the test by its co'nnection through repeat relay 50,c onductor 46 and bus 48 to the central oflice common battery 13. The power contact members of the horizontal -row 33 are connected individually to the upper bus wires of the different filament batteries F, F and F Thus the batteries B B and'B the program transmitters P, P, andP and the filament batteries F", F, and F are associated individually with the sixth, seventhand eighth vertical rows of contacts, respectively. The stepping magnet 11 .and release magnet 15 have their windings connected in multiple, one side to ground and the other side through conductor 51 to an impulse wire- 4 leading into Fig. 1 where it terminatcs in a front or normally open contact 52 of the line relay L, which contact is en.-

gaged by the armature 53 connected through wire 54 to the exchange common battery B. The conductor 51 is also connected in multiple to a normally open contact 55 engaged by the armature 56 of the relay 50, the armature 56 being connected by way of conductors 46 and 48 tothe exchange common battery P). The repeat relay 50 is controlled by the relay 42 through the armature 57 which is arranged, as shown, to close a shunt around the winding of the relay '50 byway of resistance 58, armature 57 and conductor 59.

filament. of the tube 37. The

The subscribers broadcast receiving set A is similar in all respects to the usual booster coil, common battery tele--v phone receiving set, except that the switchhook is replaced by a spring jack J arranged, upon the insertion of a plug, to close the' line circuit through the line multiples 5-6, winding 60 of the booster coil 61, transmitter 62 and automatic dial 63, while connecting the subscribers broadcast, telephone receiver 64 across the line multiple 56 in series with the coil 6165 and telephone condenser 66. They program transmitting devices P, I, and P are preferably radio receivers of a type adapted to receive radio broadcast matter from near or distant points and amplify and relay the same at audio'l'requency on to their respective bus wires 66, 67 and 68 respectively, the amplification being effected in any suitable manner such asby detection and audio amplification or a combination of radio amplification, detection and audio amplification, the audio amplification being preferably limited to one stage so as to allow a second stage of audio amplification to be made between the busses and theu ltimate. receiver. In this case the ultimate receiver is the subscribers broadcast receiver 64 and the second stage of amplification is effected through an audion tube 37 individual to each line.

In the operation of the arrangement shown in Figs. 1 and 2, the subscriber at station A operatively connects his broadcast receiving or extension set A to the line by inserting the receiver plug P in the jack' J which connects his receiver 64 across the line'multiples 5"and 6 through the booster coil windings 6065 and condenser 66 in series, and closes a path for direct current between the multiples 5 and 6 through coil 60, lower spring of jack J transmitter 62, and automatic dial 63. This energizes the subscribers line relay at the central ofiice in the usual manner by current from the central oflice common battery B, which en ergizing circuit may be traced' from the grounded side of central ofiice common battery B, conductor 68, right hand winding of line relay L, line conductor 69, to subscribers substation A, line multiple 5. to subscribers broadcast receiving set A (F ig; 2)' coil 60, transmitter 62, contacts of dial 63, conductor 6. 70, left. hand winding of line relay L'and back to the battery B. Energization of the line relay energized the line lamp L by closure of a localcircuit which may be traced from the battery B through .elements 54, L 71, 68 and back to battery B.

This causes the line lamp L at the telephone operators switchboard to glow, but only for a moment as the subscriber wanting broadcast service will immediately operate his dial to break and make his line circuit a certain number of times according to the particular program he desires which breaks and makes will cause his line lamp to flicker instead of glowing steadily and so indicate to the telephone operator that the subscriber is not calling for a telephone connection but is automatically setting up his connection for broadcast reception. As the dial 63 is, of the well known type used in automatic telephony and well understood in the art, it will not be necessary to describe the same here in detail and it sutfices to say that it operates automatically to effect one or a series of breaks of brief duration in the line circuit according to the setting of the dial each time it is set and released. The

circuit for the steppingmagnet 11 (Fig. 2)

- which may be traced from the free side of the common battery B through circuit elements 54, 5,3, 52, 4, (into Fig. 2) 51 to stepping magnet 11 and release magnet 15 in multiple and thence throughground back to the grounded side of battery B. It is to be noted here that the release magnet 15 is made sluggish in its actionso that it will not respond to the energizing current until after a lapse of time much longer than the interval between the breaks and makes of the subscribers dial 63 so that when the subscriber first closes his circuit, as just de= scribed, thestepping magnet 11 will first. operate to step the switch 9 around on 'e step releasing thedetent 19 after which, the tiine bcing understood that the switch must make five steps before its wipers engage the first set of active contacts; Thus it the subscriber, while waiting for an operator should accidentally, momentarily open his line or.

impatiently operate his 'switchhook a few times, the connector switch would simply step around over a few of the blank contacts and release as before described when the operator plugged in with her answering plug. Returningnow to the subscribers selection of a' desired broadcast program, the subscriber, shortly-after the initial closure of his line effected byhis insertion of the plug P in the jack J and before the line lamp has been energized sufiiciently long to indicate a telephone call to the operator, sets his dial to a number corresponding to the number of the broadcast program he wishes to receive, which. in the present case would be some number above five, and permits the same to release producing a number of.

breaks corresponding to the setting of the dial. Assuming the setting to be eight, the dial upon release will cause the line circuit to be momentarily opened eight times. The first five breaks in the line circuit will cause thearmature- 53 of the line relay to open and close its connectionwith the contact 52 five times thus stepping the selector switch period of the release magnet 15 having lapsed f around tonthe fifthicontact the "period of this magnet will actuate its armature to move the hook 21 up into engagement with the detent 19 and the'extension 16 into engagement withthe dog 14 which disengages the dog from the ratchet 13 and also throws the pawl 12 out of engagement with the ratchet, thus causing the switchto release and return to normal position whereupon the cam22 will throw the detent 19 out of engagement with the hook 21 and leave the armature 17 free to return to normal position when the magnets become deenergized.

In the case of a call for telephone connection this deenergization of .the magnets would occur when the telephone. operator,

in answering, inserts the plug P inthe jack J which would operate the line cut oil relay L in the usual manner causing the line relay Lto retract its armature 53 and open the circuit of the stepping and release magnets 11 and 15. To prevent the subscribers broadcast selector switch, 9 from. being stepped around and connecting broadcast matter on to his line due to one or more accidental breaks in his line circuit while the subscriber is waiting for telephone operatorv closure of the contacts -5253 being sufliciently brief to prevent actuation of the release magnet15. Upon thesixth momentary break and subsequent make of the line circuit, the witch 9 will step on to the sixth or first vertical row of active contacts whereupon-the line cut off relay L will be energized and the control of the stepping magnetill transferred from the line relay to the sleeve relay 42 of the switch circuit; The energizing circuit of the out off relay L may be traced from the common battery B (top of 2)' bus wire 48, conductor 46, windlag 0% repeat relay 50, conductor 49, upper member of the sixth contact of horizontal" to grounded'siile of the common battery B.-

Energization "of 'repeat relay 50 causes its armature 56 to engage the contact 55 thus maintaining the steppingmagnet 11 energized by current-from battery'B through circuit elements 48, 46, 56, 55, 51, 11 to ground and back to battery B, while the energizationof the cutofl' relay L (Fig. 1) disconnects the line relay L-in the usual manner which becoming dee'nergized releases its ar- 'matures 71-53, extinguishing the line lamp andopening the circuit through conductor 4. Simultaneously with the energization of the cut off relay L and repeating relay 50, the

. and causing it to return to tary release of lay 42-which causes a cuit elements 62, 63, 60, 5 into Fig. 2, 69,

relay 42 is energized by current from the common battery B through the circuit elements 48, 46, 39,

wiper 8, line multiple 2 into Fig. 1, line wire 70, multiple wire. 6, into Fig. 1, through cirinto Fig. 2, 7,. 40, 38, 45, 47, and back-to the grounded side of the common battery B. Energization of sleeve relay 42 causes its armature 57 tobe attracted andficomplet'e a shunt around the winding of repeat relay 50 by way of circuit 'elements58, 57 and 59, which shunt'causesthe relay 50 to become deenergized and retract its armature 56 opening the circuit of the stepping magnet 11 normal ready for the next step. The next. or seventh momentary break in the subscribers line circuit, which follows immediately, effects a momenthe armature 57 of sleeve remoment-ary energization of the repeat relay 50 which-in turn efiects a momentary closure of the contacts 56 50 and a momentary energization of the stepping magnet 11 to step the switch wipers around tothe seventh vertical rowof .con-

tacts. The energizing circuit'of the stepping magnet may be traced from the common battery B through circuit elements 48, 46,56, 55, 5'1, and 11 back to the grounded side of battery B. Similarly, the next or eighth momentary break in the line causes the stepping magnet 11 tobe again momentarily energized and step the switch wipers around into engagement with the eighth yertical row of contacts.

After the eighth momentary break in the line circuit the subscribers dial 63 comes to rest and maintains the line circuit closed. The line now being-closed, the sleeve relay 42 is maintainedenergized which maintains the repeating relay 50 deenergized by virtue of the closure of the shunt around its winding which in turn maintains the circuit of the stepping and release magnets 11 and 15 open at the contacts 56. The switch wipers thus come to rest on the eighth vertical row of contacts, maintaining the input terminals of the subscribers line tube 37 in operative connection with the bus wires 68 of the program transmitter P through switch wipers 25*26 and the eighth pair of contacts in the horizontal row 32; Current is supplied to the output or plate circuit of the tube-37 from battery 13, individual to the program transmitter P over circuit elements 72. 73. 23, 74, 34, plate of tube 37, filament of tube 37, 75, 35, 76, 24, 77, 78, back to battery 13*. As the coil 36 is a repeating coil of the well known type having the four windings 34. 38,39 on a common magnetic core the output or plate circuit of the tube 37 is coupled to thesubscribers line through the coils 38-39 which are included 42, 41, lower member of the sixth contact in the horizontal row 30, switch jacks in the usual manner stepping magnet in series in the subscribers line circuit as hereinbefore traced. The filament circuit of the subscribersaudion tube 37 niay be traced from filament battery F individual to the program transmitter P over the circuit elements 79, lower member of bus wire 68, 26, filament of audion tube 37, fil'ament rheostat 80, 28, 81, 82, back to battery F As the winding of the booster coil 61 at the subscribers broadcast receiving set A is included in series in the line, the broadcast matter coming thereover is repeated in the winding which reproduces the signal in the subscribers receiver 64 over a circuit which may .be traced from 65, through circuit elements 66, 63, 62, and through the receiver 64 back to winding 65 by way of the plug and jack connections P -jl As the sleeve relay 42 is held energized during the subscribers use of'his line for receiving broadcast, should a telephone operator test one'of his multiple before establishing a connection therethrough to his line, instead of the ordinary busy test of a click in the ear, she will receive a special tone test which willindicate that the line is not busy for telephone use but is being used for the reception of broadcast an emergency one the operator may plug in regardless of the busy condition. Thus a special tone test is effected by the usual tone test apparatus indicated in Fig. 2 as consisting of the inductance 87 connected in series with a circuit breaker 8 8 and inductively related to the coil 58 in series in the, test circuit. vThe energizing circuit of the coil 87 '57 is retracted removing the shunt from the repeating relay 50 which thereupon becomes energized and closes the circuit of both the and the relay magnet through connection of the armature '56 with contact 55. This circuit may be traced from battery B through the circuit elements 48, 46, 56, 55, 31, 11, and 15 in multiple to ground and back to the battery B. After the brief lapse of time required for the operation of the release magnet 15 this magnet attracts its armature which brings the extension 16 into engagement with the dog 14 to trip the same Which-in turn trips the pawl 12 allowing the switch to return to normal, hook 21 engaging the detent 19 which holds the armature 17 in its actuated position during the restoring movement of the switch and until the switch reaches the normal position whereupon the cam 22 operates to disengage the detent 19 from the so that if the call is ther attraction ofthe armature and the achook 21 and permit all parts of the switch to return to the normal position shown.

When the switch in restoring moves its ing opens the circuit of the magnets 11 and 15 at the contact 5556. This puts all the circuits and apparatus in the normal conditionshown in Figs. 1 and 2.

Form'etering the subscribers use of the radio broadcast service on a basis of time use, a meter controlling actuator 90 Fig. 2) is arranged to control the subscri ers telephone meter M (Fig. 1) through the to erative connection of the switch .circuits of Fig. 2 with the subscribers central office line terminal circuits. This control circuit may be traced from the meter generator 91 (Fig. 2) through commutator- 90,- switch 92, bus wire 93, switch 94, wire 49, the u per member of one of the contacts in t e horizontal row 33, wiper 27, test wire 3, into Fig. 1, Wire 95, high voltage winding 96, of'the meter M, to ground and back to the grounded side of the 'meter generator 91 (Fig. 2). When the meter armature 97 is retracted a sufficient distance to close the contact 98 the low voltage winding 99 of the meter M is closed thus siding in the furtuation of the meter as well understood in the art, whichactuation will be repeated at; intervals- .accordingpto theintervals of the closing and opening of the circuit meter commutator 90. These periodic registration.

of the meter during use. of the broadcast apparatus will of course be added to those produced by the actuation of the usual, telephone operators metering key 100, so that the subscribers use of the broadcast service is charged in the same units as that of the telephone use and the amount of service represented by a unit charge varied according to-the speed of operation of the commute tor 90. Where the service to some of the.

lines is to be given free the switch 94individual to'the line is opened and where the service is to be given free to all or a oup of lines the switch 92 is fopened to disconnect the commutator from the bus 93 common to all or a group as the case may be.

Referring now. to Fig. 3, .this is similar to Fig.2, just described, except that the line multiples 12 are permanently connected to the outside terminals of the coils 38 and 39 and the battery connection. to the inside -ter,-

4 minals of these coils controlled through the upper pair of wipers 7.-8 of the switch 9., and the. horizontal row 30 0f the switch bank contacts. Another difference is that the repeat relay is omitted and the stepping of the switch, after connection with the activecontacts, controlled through a back or normallyclosed contact of the sleeve relay- 42 connected to battery through an of? nor mal switch 101 controlled by ,a cam 102 on the switch shaft 10 arranged to maintain the off normal switch closed only during engagement of the switch, wipers with one of the sets of active contacts that is, from the sixth Vertical row on. As this is a modification or the switching circuit illustrated in Fig. 2 and intended to operate in place therefor, it is to be read in connection with Fig. 1. The conductors 1, 2, 3, 4, 5 and 6 of Fig. 3 tie on to the similarly numbered conductors of Fig. 1. In the operation of this circuit arrangement whenthe subscriber operates the dial 63 at his broadcast receiving set A to effect the eighth successive momentary breaks in his line circuit, thefirst six cause the line relay to close the contact 52-53 six times which in turn effects six successive energizations and deenergizations of the stepping magnet 11, the successive impulses being as before described, of too brief dura-' '(Fig. 1) through circuit elements 53, 52, 4,.

into 3, 51, 11, and through ground back steparound to the sixth vertical row of bank contacts whereupon the cut off rela (Fig. 1) is energized by current from at-' tery B (.Fig. 3) through the circuit elements 58, upper contacts of row 33 of the switch =bank'"contacts, 27, 3," L, 68, to ground and back to battery B. At the same time battery is supplied to the subscribers line in series with the sleeve relay 42 over a path which may be traced from batteryB (upper part of Fig. through upper members of row 30 of the switch bank contacts, circuit elements 7 140, 39, 42, 2, 70, to subscribers station and back by way of 69, 1, 39, 141, 8, lower contacts of row 30, back to battery B. The seventh break in the line, effected by the subscribers dial 63, effects a momentary. deenergization of the relay 42 whose armature falling back produces a momentary closure of the circuit of the stepping magnet 11 whose energizing circuit may now betraced from battery B (Fig.3), through wiper 7 to wire 140, as .before traced, .and thence through 01f normal switch '101,the cam 102 now having moved into a position to close the same, thence through circuit elements 103, 104, 105, 51, 11, and through ground back to battery B. Similarly upon the eighth break '-in the line circuit, the switch to battery B. This causes the switch 9 to eighth palr of contacts in row 32 and switch wipers 25-26. The switch wipers 23- 24 engaging the eighth pair of contacts, cimnect the battery Bi, individual to the number.

tain circuits which while the meter actuating 8 program, through conductors74 and '76 through the windings 34 and 35 of the repeat subscribers line as before traced. Also, as in Fig. 2, the filament circuit of the subscribers 'line tube 37 will be supplied with current from the filament battery A individual to the number 8 program, the connections for this being .the 'same as that of Fig. 2. Also, as in Fig. 2, the cut ofi' relay, busy test and meter control circuit 3 is completed through wiper contact 27 The circuit of the cut oil relay may be traced from battery B (Fig. 3) through the circuitelements 58, upper member of the engaged contact in row 33, 27, 3, into Fig. 1, L 68, and back 'to battery B. The tone testis imposed upon this circuit by the coupling of the tone test coil 87 with the coil 58 includedin the test circuit in the ,nsual manner well understood in the art, source 91 and commutator 90 are connected with this circuit through conductor 142.. The circuit of the meter actuating current may thus be traced through the source 91, through the circuit elements 90, 142, 143, 27, 3, into Fig. 3, 95, meter M, to ground and back to the source 91.

In Fig. 4, is shown diagrammatically, a switch circuit whichis a simplified form of the circuit arrangement of Fig. 3 in which the number of switch wipers are reduced to a minimum by delegating the control of cerare common to all the programs, to a cam actuated switch operable 'to maintain saidcircuits closed only during the engagement of the switch wipers with the program contacts. In this, as in the other switch arrangements previously described,'the contact bank of the switch is provided with several vertical rows of blank contacts, for example five in number, not shown, for the purpose of permitting the switch ,to be stepped around several steps without eiiectingconnection with any program transmitters. Parts of the present switching arrangement which are similar to and perform the same function as corresponding parts inthe previously described switching arrangement are sin'iila'rly numbered. For example, the battery supply for the output circuit of or relay.37 is furnished through wipers 23 and 24 and the top row of bank contacts, the connection between the input circuit of the subscribers line relay tube 37 and the program sourceis elitec'ted through wipers 25 and 26 and the second horizontal row of bank contacts, the filament current supply is furnished through wipers 26 and 29 and their associated contacts, and themetering contacts, and y will maintain ,ergized {disconnect the line relay, now :causes the further steppingot the the subscribers line circuit.

the subscribe1"s line tube circuit is connected through wiper fl'l and its associated contact, with the meter actuating source. All of these circuits areto be connected with sources individual to a program and so their control is delegated to the wipers which change connection with each step of the switch. Thus, cincuit connections which are not individual to a program such as the connections efl'ected through the multiple line conductors 1-2, test conductor 3, an impulse conductor 4, are controlled through the cam operated switch 145. This switch is controlled by. thecam 146 carried by the switch shaft 10 to maintain the contacts open when the switch is in its nor mal position or has moved into aposition in which its wipers are on any of the blank its contacts closed in any position of the switch in which theswitch Wipers are in engagement with a set oftheprogram contacts. Another feature characteristic to the present switch arrangement is the position of the individual meter IM individual to the switch circuit so as to meter only the use of thesubscribers linefor broadcast reception. As with the other switching diagram, the present diagram is to be read in connection with F ig. 1, the conductors 1, 2, 3, and 4 of Fig. 4 tying onto the conductors 1, 2, 3 and 4 of Fig. 1 respectively.

In the operation of this arrangement, the impulses sent over wire 4 from the subscribers line relay in Fig. 1, pass directly to the stepping magnet 11 through conductor 146 until the switch has been stepped the sixth row of contacts whereupon the contacts of switch 145 are closed, the sleeve re lay 42 energized in series with the subscribers line and the cut oil relay in- Fig. 1 enwhich switch to be controlled through the relay 4?. as a repeating relay responding to breaks in The'circuit of thec-ut off relay (Fig. 1) may be traced from battery B (Fig. 4), supervisory lamp 147,

conductor 148, contact of switch 145. con;

ductor 3, into Fig. 1, cut off relay L conductor 68 to ground and back to battery B. The energization of the cutoii' relay L causes the line relay L to become decnengized and open the circuit through the impulse conductor 4 as be fore described in connection with Figs. 1 and 2. At the. same time the cut oft relay is deenergizcd to bring about the disconnection ot the circuit through conductor 4, the sleeve relay 4?. is energized in series with the subscriheus line by a circuit which may be traced from battery B through the circuit elements 39, 42, 2, 70, over the subscribers line and back by way of circuit elements 69, 1, 38, to battery B. Upon the next momentary break in the subscribers line circuit the relay 42, being around to energized in series therewithfis momentarily deprived of current which causes a momentary retractionof its/armature, which in turn closes thecircuit of the stepping magnet 11' which maybe. now traced from battery B through the circuit elements 104;

105, 146, 11, to ground and back tobattery B. Thus, each momentary break in the subscribers line circuit causes the switch to make one step. YVhen the "switch comes to rest-with its switch wipers on the-vertical row of. contacts corresponding to-the-desired program, the'sleeve rel ay 42 remains energized maintaining a shunt around the lamp 147 through resistance 149 thus extinguishing the signal light. This is the operating position of the switch, and during the main tenance of this connection, assuming the switch wipers to be in contact with the ver:

tical row of bank contacts associated with the number -7 program, the individual, broadcast service meter will be intermittently energized in a circuit which may be traced from the meter energizing source 91,through commutator 151, switch 152, upper member of the bottom pair of contacts in'the eighth row, switch wiper 27, conductor 153', meter ere .For the purpose'of assigning different rates to difierent programs the switches 152 and 154 inclu'ded in the meter circuits of the dif-- ferent programs respectively, are arranged, as shown, with different contact connected with the different commutators 150 and 151, respectively. Thus, with the meter control commutators 150 and 151 associated with difi'erent programs, the subscribersservice charges as recorded by his broadcast meter 1M will vary according to the particular program taken by him. To enable the operator or supervisor having charge'of a number of switching devices like the present one, to listen in on the subscribers line in the usual manner as in a telephone operators'cord circuit for the purpose of .communicating with the subscriber, a listening key K is. provided arranged to connecta suitable listening set, not shown. The subscriber may apprise such supervisory of hiswish for some special service by making several suc cessive momentary breaks in his line circuit much in excess. of that required for the stepping of the switch to an of the setsof program contacts during w 'ich the supervisor noticing the apparent constant flickering of the supervisory lamp 147, will operate the listening key K to ascertain the wants of' No.746,357, filed Octo er 28, 1924.

the subscriber. To enable the supervisor to call the subscriber during the connection of his line through the switch mechanism, a special signaling key S i S provided which is arranged to connect the inductance coil 154 across the subscribers line, which coil is inductively connected with the special tone signal circuit and thus puts the signal on the line to' be heard in'the'sub'scribers loud speaker. To enable the subscriber to receive other broadcast items not on the programs to which his switch has access, the last vertical row of conta'cts'in the switch have their program contacts such as 155 connected to a special program trunk 156 terminatlng in a 'ack 157 situated before what maybe termed a special program operator who has access to trunks leading to other stations' providing different broadcast items,

and'who is also provided with means, such as'telephone plugs forming the terminals of such trunks, for connection of any of said trunks to the special, program contacts-155 through the jack157, andshort trunk 156.

When the subscriber desires such special items he signalswtl'ie supervisor in charge of the broadcast service by sending in the ex-' cessive number of breaks to signal the super visor through actuation ofthe lamp 147 as before described, theextra number ofbreaks, in the line circuit causing theswitch to step around to the last vertical row of contacts and there come to rest, which disconnects .the subscribersline from all of the regular programs and connects it through the switch wipers 2526 and special program contacts 155 to the .trunk' 156 terminating in the jack 157. The supervisor listening in through use of the key K may now ascertain the wants of the subscriber and communicate the same to the special program operator over a suitable order circuit not shown. The

special program operator may then give the subscriber the program or'item desired, by

inserting the terminal plug of the-appro- 'priate trunk in the jack 157. This trunking arrangement for. supplying "the special pro grams from other stationswill be clearlyiunderstood from an inspection of Figs. 5 and 6. In Fig. '5 is diagrammed a portion of a general system of broadcast distribution comprising a master station A, district sta- Y tions B, subscribers central stations 0, and subscribers substations D, the relation of the stations A, B, and 0 being the same as that described in my copendin application Seripl t suflices here to say that'the station A is a master station for the system having means for originatingor relayingbroadcast matter to the B stations either by radio or over trunk lines, such as 158 and 159, that the B stations have means for originating or relaying broadcast matter from the A station or stations, outside the system to 0 stations,

and that the 0 stations, together with the subscribers substations D are provided with means in the form of the circuits herein previously described in detail, for originating or relaying broadcast matter from the B stations to the subscribers stations D. The broadcast matter is originated or, received from the other stations and utonto the program contacts of the subscribers selector switches by any known or other suitable form of apparatus symbolized at P, P and P in Figs. 2, 3 and/1. 1

In Fig. 6 is shown diagrammatically, the special trunking system enabling a subscriber at a D station to extend his line beyond his associated central station either directly, or through other stations of the system to some particular station for the purpose of' receiving the broadcast program there originated or there available through suitable relay apparatus, for example, station B For thispurpose, the special program operator at the C station is provided with a link circuit LC capable of connecting a trunk terminaljack 160 with the subscribers special jack 157 (the same as 157 of Fig. 4) through a detector and. amplifier unit DA. The jack 160 forms the terminal of a trunk 161 terminating in the B sta tion B in the output circuit of a line amplifier tube 137 whose input circuit terminates in a jack 162. Similarly, the station B is provided withcircuit. LB arranged to connect the jack 162 with the jack 163 to an amplifier unitn-LA, the jack 163 forming the terminal of a trunk 159 which terminates in the output circuit of a line tube 237 at the AA station, the input circuit of which tube terminates in the jack 164. At the A station is provided an amplifying link circuit LA the same as that of station B arranged to connect the jack 164 with ajack 165 forming the terminal of .a trunk 158 terminating in a line tube 337 andjack 159 at station B in the same manner as that of the trunks 159 and 161. At the station B is provided a link circuit LB similar to those at stations A and B and arranged to connect the jack 159 with the broadcast program apparatus 166 whichniay be a local source of broadcast matter or suitable relay device capable of relaying broadcast from some other stations. Thus, with the trunking system sodescribed the subscriberat a D station may extendhis line to the broadcast transmitter;160- ofthe station B over the trunking connection which may be traced from 160 through the trunking elements L13 159, 337, 158, 165., LA, 164:, 237, 159, 163,-LB, 162, 137,161, 160, LG,157, 37 to subscribers station D. In the present illustration-this broadcast matter is transmitted from the station B over the trunks 158, 159, and 161 by carrier current, which is detected and amplified 'in the detector amplifier unit DA at the C-station and from thence transmitted to the subscribers station at audio frequencyor in the form of'the original modulations, the 'amplifier'units IA at the stations B A, and B being operable on the intermediate or carrier current frequency. In Figs. 5 and 6, the trunks 161,

v 159 and 158 are symbolical of a plurality of trunks which afford trunking distribution out from any of the stations to several 0 stations directly or through other stations. It is also to be noted that the outgoing terminal of each trunk line is provided with a line tube similar to that of thesubscribers linetube which acts as an amplifier or relay so that throughout the several links, the line tubes or relays will 0 crate to eiiect gradual amplification throng out the distribution thus avoiding the losses and the necessity for currents of large magnitude incident to long' distance distribution without the use of increments of power between the source and destination. It will be obvious that where conditions are favorable, the amplifiers IA at the intermediate stations A, B, etc. may consist of but one step or may'even be omitted or replaced by suitable coupling means, the line tubes or relays 137, 237, etc, being relied upon for eflectin'g the necessary amplification.

Thearrangement of circuits and apparatus for carrying out the idea of distribution with gradual amplification or increments of power at a broadcast distributing central is diagrammatically shown "in Fig. 7, where a source of audio signals is indicated at 167, the signals of which are distributed through a transformer 168 and a group of several amplifier tubes 169-in multiples to the input side of a suitable coupling means such as the audio transformer 170, the output side ofwhich distributes through several amplifier tubes 37 to as many trunks or line cir- 1 cuits 17 3. The line circuits, 173 represents the subscribers lines such as the subscribers line 69-70 of Fig. 1, while the amplifier tubes 37 represent the individual linetubes or" relays such as 37 of Figs. 2, 3, etc. It

-will thus be seen that with this arrangement the amount of power in any of the intermediate circuits may be considerably less than the total amount of power distributed.

It is to be noted that the'broadcast matter may if desired be put on the program contacts of the switch banks in the form of modulated carrier current, in which in- 1. In a system of radiobroadoast distribution, a central station, subscribers stations and wire lines interconnecting them, means at the central station to receive broadcast modulated waves, and means also at the central station, individual to the lines, for connecting with saidbroadcast receiving means and adapted to relay the modulations received to the subscribers over theii' \v1re lines, the said line relaying means consisting of individual vacuum tubes, or valves, one for each line, at the central station, and means whereby the input sides of said line tubes are connected to receive the output of the central oifice transmitting or relay apparatus, and the output side of each line tube is connected to its own line, together with means at each subscribers station'to controlthe connection of his own line tube sit-central,- and to disconnect the same when not receiving, and -line service meterlng means controlled in said connection and, disconnection. l

2. In a system of radio broadcast distribution, a central station, subscribers stations and wire lines interconnecting them,-

means at the central station to receive broadcast modulated Waves, and means also at the central station, individual to the lines, for connecting with said broadcast receiving means and adapted to relay the modulations received, to the subscribers over their wire lines, the said line relaying means consisting of-individual vacuum tubes; or valves,

connection, said metering means being 10 cated at the central station. 3. In a system ofr'adio broadcast distribution, a central station, subscribers stations and wire lines "interconnecting them,- means at the central station to IGCBIVQbIOHClcast modulated waves, and means also at the central station, individual to the lines, for connecting with said broadcast receiving means and adapted to relay the modulations received, to the subscribers'over their Wire lines, the said line relaying means consisting of individual vacuum tubes, or valves, one for each line,-at-the" central station, and means whereby the input sidesof said line tubes are connected to receive the output of the central oflice transmitting or relay ap paratus, and the output side ofeach line tube is connected to its own line, together with means at each subscriber,s station to control the receiving connection of his own line tubeat central and to disconnect the same when not receiving, and line service metering means controlledin said connection and disconnection, said metering means being located at the central station and individual to the lines.

4. In a system of broadcast distribution, a central station and subscribers stations and Wired line circuits interconnecting them, a plurality ofbroadcast electrical wave transmitters at the central station, and individual telephone relay units also at the central station, one for each subscribers line circuit, with switching means to connect the subscribers relay units interchangeably with the central station broadcast transmitters, said switching means being selectively controlled by the subscribers, together with service metering means associated with each subscribers line and means to actuate the same at variable rates according to the central office transmitter or item of program selected by the subscribers.

5. Ina system of broadcast distribution, a central distributing statlon. subscribers stations, means at sald central station for distributing different items of broadcast programs to the subscribers, means at the subs'cribers stations controlled by the subscribers independently of other subscribers for selecting the available items they individually desire to receive, and means for metering the service rendered each subscriber differentially according to the items selected by him. v

6. In a system of broadcast distribution,

a central distributing station, subscribers stations, means at said central station For distributing difi'erentitsem of broadcast pro-' grams to the subscribers, means at the subscribers stations controlled by the subscribers independently of other subscribers for g selecting the available items they individually desire to receive, and means for meter-- ing the service rendered each subscriber different-ially according to the items selected by him, said metering means being located at the central stat-ion.

7. In a system of broadcast distribution,

a central distributing station, subscribers stations, means atsaid central station for distributing differentitems of broadcast pro grams to the subscribers. means at the sub scribers stations controlled by the subscribers independently of other subscribers for selecting the available items they shall .in-

dividually desire to receive. and means for v metering the service rendered each subscriber differentially according to the items selected by him, said metering means being located at the central station, with means interchangeablyassociated withthe difierent distributing means for determining the difl'erent rates of'the metering.

In testimony whereof I hereunto ,afiix my signature. v V

I IFJDWA RD CLEMENT.

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