US2385720A - Telephone system - Google Patents

Description

p 1945' v I. MOLNAR 2,385,720

TELEPHONE SYSTEM I ADAF WER CIRCUIT 25 CONTROL IN R25 R230 234 DIGIT COUNTING SW 275 INVEN TOR.

IMRE MOLNAR ATTORNEYS Sept. 25, 1945.

l. MOLNAR TELEPHONE SYSTEM Filed Feb. 9, 1942 4 Sheets-Sheet 4 I27 I4 Is 7' Is; 370) 3'II 372 LINE I E- [CIRCUIT FINDER SELECTDR coNN.

REV. BATT. LINE T0 H54 FINDER I II:

COMMON EQUIPMENT |6Ia l6lb '||-'l|l|lm Z; 41L OPER I ,t 20 SWITfigIIBOARD I" I620 |62b I J I657 Wm l 55 1 I66) TOLL I l IGGa I 360', SELECTOR 37 I63. C22 TOLL 2L OlN CONN CONTROL I64 CONN INVENTOR.

IM RE MOLNAR ATTORNEYS Patented Sept. 25, 1945 TELEPHONE SYSTEM Imre Molnar, Chicago, Ill., assignor to Automatic Electric Laboratories, Inc., a corporation of Delaware Application February 9, 1942, Serial No. 430,046

45 Claims.

The present invention relates to measured service telephone systems and, more particularly, to improved apparatus for controlling the collectin and refunding of coins deposited in the coin receiving means of paystations forming a part of an automatic telephone system.

It is an object of the present invention to provide, in an automatic telephone system, improved and exceedingly simple apparatus for controlling the coin collecting and refunding operations required incident to'the use of connections involving the paystations embodied in the system.

It is another object of the invention to provide, in an automatic telephone system, improved and simplified apparatus forpermitting an operator to control the collecting and refunding of coins deposited at a paystation of the system at any time after a connection is established between the paystation and the operator position.

According to another object of the invention, the selective control of the coin mechanism at the paystation is effected by the operator through auxiliary automatic switches which are entirely separate from those switches used in setting up the connection between the operator position and the paystation.

According to a further object of the invention, provisions are made in the apparatus for transmitting to the operator a signal which indicates that the coin control operation directedby the setting imparted to the auxiliary automatic switches is being effected.

In accordance with another object of the invention, the coin control apparatus is so arranged that the coin mechanism at the paystation is automatically operated to refund deposited coins incident to the extension of a connection from the paystation to the operator position.

According to another object of the invention, the coin control apparatus is arranged to switch the conductors of a calling paystation line through to the conductors of a trunk in extending a connection to the operator position in order to permit the operator directly. to control the coin mechanism at the paystation, providing the operator position is equipped with the necessary facilities for such control.

It is another object of the invention to provide a paystation control circuit which includes improved facilities for permitting the paystation user to make certain free service calls without first making a coin deposit, and for preventing a local call connection from being set up unless the correct coin deposit is made at the paystation before the call is initiated.

According to still another object of the invention, the paystation control circuit is equipped with improved facilities for insurin the positive response of the coin mechanism of a connected paystation when circuits are set up therefrom for operating the mechanism.

In accordance with another object of the invention, improved facilities are provided in the coin control circuit for delaying the transmission of a dial tone signal to a calling paystation until -a coin is deposited at the paystation.

It is still another object of the invention to provide improved apparatus of the character described, which is so arranged that the regular automatic switching apparatus of the system may be used in completing local connections and in extending connections to a toll operator position without sacrificing any of the required paystation control features.

It is a still further object of the invention to provide improved and exceedingly simple paystation circuit apparatus which is characterized by the operatin features briefly referred to above, i adapted for use in conjunction with the individual paystation lines, and is so arranged that all required paystation control operations are effected with a minimum of equipment.

The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understood by reference to the specification taken in connection with the accompanying drawings in which Figs. 1, 2, 3 and 4, when placed side by side in the order named, illustrate a telephone system having incorporated therein a paystation line adapter circuit characterized by the features of the present invention.

In general, the system as illustrated in Figs.

1 to 4, inclusive, of the drawings, comprises an automatic exchange which is provided with facilities including a toll operator switchboard I9 for handlin toll traffic to a distant central office, not shown. In the particular arrangement illustrated, the automatic exchange is designed to serve 1,000 lines or less, two of these lines l0 and II being shown as extending to the substations A and B, respectively. The subscriber lines of the system may be of the single party type or of the multiparty type as desired, the line being illustrated as serving only the substation B. This substation is of the conventional common battery type of which several well known commercial embodiments are available. The'substation A, on the other hand, is of the paystation type. In brief, the equipment provided thereat comprises a transmitter 30, a receiver 3I a dial-operated calling device 32, a hook switch 34, an induction coil 35, and a ringer 36. The enumerated circuit elements are interconnected in a.well known manner to form a substation circuit of the well known antiside-tone type. The equipment at the substation A also includes a coil mechanism which is schematically shown as includinga coin chute 31, a coin gate 4|, a polarized control magnet 30, and two sets of circuitcontrol contacts 33 and 40.

For the purpose of setting up local call connections between the lines terminating in the exchange and of extending connections frosn these lines to the toll operator switchboard I9, automatic switching equipment is provided which comprises a plurality of finder-selector links and a plurality of connectors, together with line circuits individual to the various lines. Thus the lines I and II are illustrated as terminating at the exchange in line circuits I2 and I3, respectively. One 01' the finder-selector links is schematically shown as comprising a finder I4 and a selector I5. The selectors each have access to a plurality of groups of connectors, one of which includes the connector I6.

The selectors also have access to a group of reverse battery repeaters tributors I1, each associated with a diflerent group of the finder-selector links and a different group 'of lines terminating at the exchange, are provided in order to assign idle ones of the associated links to the use of calling lines in the associated line groups. Thus the distributor I1 is, provided for the purpose of assigning the links in the group including the link I4, I5, to the use of calling lines in the line group which includes the line I0.

For the purpose of handling toll calls routed to the toll operator switchboard l9, automatic toll switching equipment is provided which includes a plurality of toll selectors including the selector 20 and a plurality of toll connectors including the connector 2I. These switches may on y be seized from the toll switchboard I8 and may be used to extend connections to all lines terminating in the exchange. v

In order to control the coin mechanisms respectively provided at the substations of the paystation -type each paystation line is directly I terminated in the exchange in a paystation line adapter circuit. Thus an adapter circuit 25 is shown as being connected between the conductors of the line I0 and the line circuit I2. This circuit and the similar circuits terminating the other paystation lines of the exchange have associated therewith common equipment 23 which includes two distinctive signal current sources minal of which is connected to the conductor I62. vators at the switchboard I9 selectively to control In order to permit the operator or operthe application of refund and collect potentials to'the conductors of a paystation line involved in a toll connection, coin control connectors 22 are provided which may 'be seized-from the switchboard I9' through the toll selectors 20 and may Y be directed to engage either the} coin collect ter-- ings of the control relay R250.

minal or the coin refund terminal individual to any one of the adapter circuits.

The various adapter circuits include identical parts and are identically wired. Briefly considered, the illustrated circuit 25 includes a line relay RI 50, a slow-acting hold relay R200, a pulse cut-off relay R2I0, a slow-to-release transfer relay R220, a slow-to-operate' coin relay R230, a slow-to-release digit relay R300, a pair of backbridge relays R3I0 and R320, a switching relay RI30, an incoming call relay RI40, a pickup relay'R350, five coin control relays RI00, RIIO, RI20, R330 and R340, and three additional control relays R240, R250 and R250 which perform general circuit control operations. The relays RI00 and R340 are of the slow-to-release type and the relay R3I0 is of the well known electropolarized type. The adapter circuit also includes a digit counting switch 215 which is of the well known minor type and is provided for controlling the pulse cut-oil relay R2I0. More specifically, this switch includes a single set of contacts 216 of eleven points, a wiper 211, a magnet 218 for driving the wiper 211 over the contacts of the contact set 215, a release magnet 219, and a set of oil-normal springs 200. The supervisory signaling facilities provided in association with the adapter circuit 25 include a signal lamp 356 and a delayed ala signaling circuit schematically illustrated at 3 1.

O utgoing local paystation calls In considering the operation of the system and, more particularly, the operation of the adapter circuit 25, it'may be assumed that a call intended for the substation B is originated at the paystation A. When th receiver 3| provided at this paystation is removed from the supporting hook of the hookswitch 34 to initiate the call, a circuit is completed for energizing the windings of the line relay BI 50 in series with the wind- This circuit extends from ground by way of the contacts 32I, the lower winding of R250, the contacts I34 and I03, the pulsing contacts of the calling device 32, the transmitter 30, the upper and middle con-;

tacts of the hookswitch :4, the middle win rie of the induction coil 35, the contacts 01 the-busy contacts I52 to.complete an obvious circuit for energizing the slow-acting hold relay R200. At

its contacts I53, the relay RI50 opens a. point in the operating circuit for the digit relay R3003" At its contacts I5I,the relay RI50 completes a local loop circuit which extends between the adapter circuit 25 and the line circuit I2. This loop circuit may partially be traced as extending from the positive talking conductor 31l by way of the contacts I5I, the lower windings of R3I0 and R320, and the contacts I33 and 30I to the negative talking conductor 310. I

The holdrelay R200, upon operating, closes its contacts 20I to prepare or complete a path for short-circuiting the impulsing springs I5I of the line relay RI50. At its contacts 202 and 203, the relay R200 prepares a path for short-circuiting the windings or the control relay R240. At its contacts 203, the. relay R200 also prepares certain operating and locking circuits described with particularity hereinafter. At is contacts 204, the relay mli prepares the above-mentioned operating circuit for the relay R333. At its contacts III, the relay R200'opens a point in another circuit for energizing the digit relay R300 and a point in one of the available operating circuits for the coin control relay RI". At its contacts 230, the relay R203 opens a point in the incomplete.operatlng circuit for the release magnet 213 of the digit counting switch 210.

when the above-traced bridging path between the conductors 310 and 3" is completed, the line relay of the line circuit l2 operates in the usual manner to mark the vertical and rotary positions of the line l in the banks of the finders havin! access thereto, to mark the circuit 23 against seizure, and to impress ground potential upon the start lead extending to the distributor i1, In response to the latter operation the control equipment of the distributor l1 functions to initiate the operation of a previously selected finder to search for the calling line I0. Assuming that the illustrated finder-selector link l4, l has been previously set up for use by the distributor l1, the finder I4 thereof first elevates its wipers to a position opposite the level of contacts in which the conductors extending to the circuit 23 are terminated and then rotates these wipers until the particular set of contacts individual to the line I 0 is found. Incident to the seizure of the adapter circuit 25 by the finder II, this finder operates to extend the loop circuit from the adapter circuit to the selector l5, and to cause the operation of the cut-off relay embodied in the line circuit 12. When this cut-off relay operates the distributor i1 functions to select another idle link and the windings of the line relay embodied in the line circuit l2 are disconnected from the talking conductors 310 and 31l. Also incident to the switch-through operation of the finder ll,

this finder and its associated selector l5 are marked as busy in the banks of the link selecting switch embodied in the distributor H; the selector I5 is conditioned to respond to impulses transmitted thereto from the adapter circuit 25; and the control conductor 313 is connected .to ground. It will be noted that this conductor is connected through the upper winding of the incoming call relay R140 and the contacts 2b of the busy key M2 to the private conductor 312. Accordingly when the control conductor 313 is connected to ground, the adapter circuit 25 and the line in are marked as busy in the bank contacts of the connectors having access thereto. It will also be noted that when ground potential is applied to the control conductor 31.3, the lower winding of the relay RIM is energized in series with the resistor I43. The current traversing this winding is insuificient to cause the operation of the relay Hi 40.

When the loop circuit is initially completed between the adapter circuit 25 and the line circuit l2, the respective lower windings of the two backbridge relays ,R3i0 and R320 are both energized therein. The relay R3l0 does not operate when its lower winding is alone energized. When ground potential is thereafter applied to the control conductor 313, the upper winding of this relay is energized in an obvious circuit. At this time, the two windings of the relay R3l0 produce opposing magnetic fields and, accordingly, this relay does not operate. The relay R320 operates when energized in the above-traced loop circuit and opens its contacts 32l to include the seriesconnected windings of the control relay R2 in the calling loop circuit extending to the paystation A. When thus energized the relay R2" opens its contacts I further to interrupt an incomplete operating circuit for the magnet 213.

The starting of the dialing operation at the paystation A depends upon the character of the wiring used at this paystation, and,also upon the character of the wiring used in the adapter circuit 25. With the illustrated paystation circuit arrangement the impulsing springs of the calling device 32 are short-circuited through the contacts 40 of the coin control mechanism and the strap Y until such time as 'a coin is deposited in the coin chute 31. It will be understood, however,

that the strap Y may be omitted from the paystation wiring, whereby the impulsing springs of the calling device 32 may be used to direct automatic switching operations before coin deposits are made. On this point it will be understood that immediately a loop circuit is established between the adapter circuit 25 and the selector I 3, the control equipment of the selector functions in a well known manner to impress dial tone signal voltage upon the talking conductors 310 and 3H. If the W straps shown in Fig. 2 of the drawings are provided in the adapter circuit, this dial tone ignal voltage is impressed by way of these straps, the condensers 221 and 228, and the contacts "1, I34, I0! and I03 across the talking conductors of the line iii to energize the receiver 3| provided at the substation A and thus inform the calling party that the dialing operation may be started. 0n the other hand, if the W straps shown in Fig. 2 of the drawings are omitted from the wiring of the adapter circuit 25, the dial tone signal current path is held open at the contacts 23l and 233 until such time as the coin relay R230 operates. On this point it is noted t er that if a coin deposit is to be.a prerequisite to the starting of the dialing operation at the paystation A, the strap Y is provided in the adapter circuit so that the contacts 2 are shunted when the relay R200 operates. So long as these contacts are short-circuited, the line relay Rl50 is rendered ineffective to repeat impulses transmitted thereto from the paystation A to the selectorl5. Hence, if the Y strap is provided and the W straps are omitted, a coin deposit at the paystation A is a prerequisite to effective operation of the calling device 32 regardless of the character of the wiring used at this paystation. On the other hand, if the Wstraps are provided and the Y strap is omitted, the dialing operation may be started at the paystation A without a coin deposit, and a signal to that effect is transmitted to this paystation immediately after the receiver 3| is removed from the supporting hook of the hook switch 34.

Assuming now that the illustrated paystation circuit arrangement is used, and that a coin is deposited in one of the coin chutes immediately after the call is initiated, the coin mechanism functions to close the contacts 39 and open the contacts 4|, whereby the windings of the magnet 38 are connected between the positive side of the line i0 and ground and the path short-circuiting the pulsing springs of the calling device 32 is opened. When ground potential is applied to the positive conductor of the line l0, the current flow through the lower winding of the relay R250 is decreased, and that through the upper winding of this relay is increased. When the energize.- tion of these two windings is thus unbalanced, the differential relay R250 closes its contacts 23! to its contacts 235, the relay R230 opens a point in one of the operating circuits for the pulse cutoff relay R2I0. At its contacts 23I and 233, the relay R230 completes the above-described dial tone signaling circuit, assuming that the illustrated W straps are not provided. At its contacts 232, the relay R230 opens the above-described path short-circuiting the impulsing contacts I5I of the line relay RI50, thereby to render the line relay effective to transmit impulses to the selector I5, assuming that the Y strap i provided in the wiring of the adapter circuit 25.

It will be understood that during the dialing of each digit of the directory numiber designating the desired substation B, the impulsing springs of the calling device 32 are opened and closed one or more times to transmit a corresponding number of impulses to the line relay RI50. This relay, in following the impulses of the first digit, opens and closes its contacts I 5| to repeat the impulses to the selector I5. Upon restoring at the beginning of the open-circuit period of the .ther prepares the operating circuit for net 210.

the a A l The control relay R250, upon restoring, opens its contacts 26I further to interrupt the abovetraced operating circuit forthe coin relay R230. The relay R240, upon restoring, closes its contacts 2 to complete the prepared operating circuit for the magnet 210, this circuit extending from ground by way of the contacts 3I6, 260 and 2, and the winding 01' the magnet 210 to battery. When thus energized the magnet 210 attracts its operating pawl, thereby to condition this pawl to actuate the wiper 2'" one step when the magnet 210 is subsequently deenergized.

The selector I5 responds to the impulses oi the first digit by elevating its wipers to a position opposite the level of bank contacts through which access is gained to the connectors having access to the called line II. Incident to the vertical movement of the selector wipers the previously described dial tone signaling circuit is broken in I the selector to terminate the transmission of signal current to the paystation A.

from ground b way of the contacts I53 and 204,

and the'winding of R300 to battery. Upon operating, the relay R300 closes its contacts 302 to exclude the lower windings of the back-bridge relays R3I0 and R320 from the loop connecting the adapter circuit 25 with the selector I5, thus causing the release of the relay R320; At its contacts 305, the relay R300 prepares one of the operating circuits for the coin control relay RI00. At its contacts 303, the relay R300 opens the operating circuit for the coin relay R230. At its contacts 304, the relay R300 completes the prepared operating circuit for the control'relay R260, this circuit extending from ground by way of the contacts 203, 304 and 265 and the winding of R260 to battery. Due to the slow-to-release characteristics thereof, the hold relay R200'and the digit relay R300 remain operated during each series of impulses transmitted to the adapter circuit 25.

The relay R320, uponreleasing', closes its contacts 32I to exclude the series-connected windings of the control relay R240 from the calling loop circuit'and thus improve the response of the line relay RI50 to the impulses transmitted thereto over the line I0. The control relay R260, upon operating, closes its contacts 26I and 262 to short-circuit the windings of the control relay R250 and thus further lower the resistance of the calling loop circuit, whereby the response of During the inter-digit pause between the first and second digits; the line relay RI50 remains in its operated position for a time interval sufiicient to cause the release of the digit relay R300. The latter relay, upon restoring, opens its contacts 304 to interrupt one of the above-traced paths short-circuiting the windings of the control relay R240. At its contacts 302, the relay R300 opens the path short-circuiting the respective lower windings of the two back-bridge relays R3I0 and R320, whereby these windings are again included in the loop circuit extending from the adapter circuit 25 tothe selector I5.

winding is again energized, the relay R320 opens its contacts 32I -to again include the windings of the control relay R240 in the callingloop circuit. The relay R240v now reoperates and opens its contacts 2. to deenergize the magnet 210. thus permitting the wiper 211 to be stepped one step from the, illustrated normal position thereof.

Also during the inter-digit pause between the first and second digits, the selector I5 automatically rotates its wipers, in a well known manner, to seize the first idle connector of the group selected during the vertical movement of its wipers. Assuming that the'connector I6 is the first available idle connector, the selector I5, upon rotating its wipers to engage the contacts terminating the conductors of the trunk incoming to this connector, stops the rotary movement r of its wipers and extends the loop circuit from the adapted circuit 25 to the connector I6. When the connector I6 is thus seized the control equipment thereof is conditioned to respond to the impulses of the second and succeeding digits of the directory number designating the desired substation B, and ground potential is returned over the test or release conductor of the trunk incoming to this connector to provide circuits for preventing the release of the finder-selector link I 4,

I5 and the line circuit I2.

The four relays RI50, R300, R320 and R240 re- 'spond to the impulses of each succeeding digit of the directory number designating the desired substation B in the exact manner explained above. From this explanation it will be understood that the relays R300, R320 and R240 cooperate to transmit a current pulse to the operating magnet 218 of the digit counting switch 215 in response to each digit dialed at the calling paystation A. Thus, the wiper 211 is stepped one step for each dialed digit; Incident to the When its lower aaemao operation of this wiper to its first oft-normal position, the oil-normal springs 280 are closed to preparea circuit for energizing the release magnet 210. The purpose of providing the digit counting switch and the pulse cut-of! relay R2l0 controlled thereby,.is to prevent, under certain circumstances, the line relay R150 from repeating thew impulses of more than a predetermined numberof digits: to the automatic switching equipment seized through the adapter circuit 25. In this regard. it willbe noted that with the conductor202 connected to the third contact of the contact set 210 in the manner illustrated, a circuit is completed for energizing the pulse cut- ,of! relay R210 after two digits have been dialed into the adapter circuit 25. This circuit'extends from ground by way of the contacts 203, 303 and 345. the wiper21l,.the conductor 282, the contacts 215 and the upper winding of R210 to battery. It will be noted that this circuit is completed at thewiper 2'11 and the contact terminating the conductor 282 shortly following the end of'the second digit dialed into the adapter circuit 25. When energized thereover, the relay R210 first locks up in a, circuit which includes its preliminary make contacts 212 and the contacts 203. After this circuit is completed, the relay R210 opens its contacts 215 to interrupt its operating circuit as traced above. At its contacts 214, the relay R210 opens the prepared operating circuit for the switching relay R130. 1 At its con tacts 213, the relay R210 prepares the operating circuit for the transfer relay R220. At its contacts 211, the relay R210 prepares or completes the above-traced path for short-circuiting the impulsing contacts 151 of the line relay R150. In this regard it will be noted that if the coin relay R230 is operated, the short-circuiting path just mentioned is held open at the contacts 232 and, hence, the operation of the pulse cut-ofl relay R210 is ineffective to short-circuit the pulsing contacts 151 of the line relay R150. On the other hand, if no coin has been deposited at the paystation A to cause the operation of the coin relay R230, and the Y strap is omitted from the wiring of the adapter circuit 25, the pulse cut-off relay R210, in operating to close its contacts 2| I, short-circuits the pulsing contacts 151, thereby to render the line relay R150 inefl'ective to repeat impulses to the switch train succeeding the adapter circuit 25.

More specifically stated, the purpose of the arrangement just described, i. e., that comprising third and. if required, additionaldigits, are repeated to the connector 16. by the line relayR150.

the digit counting switch 215 and the pulse cutoiI relay R210, is to permit certain free service numbers to be .dialed into the adapter circuit 25 without a coin deposit at the paystation. Thus in the arrangement illustrated, wherein the conductor 282 is connected to the third contact of the contact set 2'16, a single digit may be dialed into the adapter circuit 25 without a coin deposit. This digit may designate the group of trunks extending to the toll operator switchboard 19, for example. Alternatively, the digit may designate additional groups of trunks, such, for example, as information trunks, over which free service connections may be set up to other operator positions of the system.

In the specific case under consideration, wherein it is assumed that the coin relay R230 is operated, the operation .of the transfer relay R220 at the end of the second digit is not effective to prevent the line relayR150 from repeating impulses to the switch train succeeding the adapter circuit 25. Accordingly, the impulses of the second,

This connector responds to the impulses of the second digit by selecting'the group oi ten lines in which the called line-1121s included. It responds to the impulses of the third digit by-selecting the called line 11 from the selected group of ten lines. If this connector is'arranged for selective code or selective harmonic ringin an additional digit may be required in order to select the particular code or ringing frequency which designates the particular substation -B desired by the calling party. At the end of the dialing operation the control equipment of the connector 16 functions in a conventional manner to test the idle or busy condition of the selected line; to return the usual busy signal over the calling end of the connection if the line is busy; and to transmit ringing current of the proper code or frequency to signal the substation B overt he line 11 in the event this line is idle at the time it is selected. I

When the call is answered at the substation B, the control equipment of the connector 16 operates to reverse the direction of current flow over the loop circuit including the respective lower windings of the two back-bridge relays R310 and R320. In response to this operation the relay R310 closes its contacts 313 to fully. energize its upper winding. The relay R310 then closes its contacts 314 and opens its contacts 315, thereby to exclude the lower winding of the relay R240 from the loop circuit extending to the calling paystation A. At its contacts 311 and 312, the relay R310 excludes the lower winding of the line {relay R150 from the loop circuit extending to the calling paystation. Thus the current flow over this loop circuit is increased to enhance the operation of the transmitter 30. At its contacts 316, the relay R310 opens a point in the prepared operating circuit for the coin controlrelay R100 and a point in the above-traced operating circuit for the'rnagnet 218. At its contacts 311, the relay R310 completes the above-mentioned operating circuit for the transfer relay R220, this circuit extending from ground by way of the contacts 311 and 213, and the winding of R220 to battery.

The relay R220, upon operating, closes its contacts 221 to prepare a locking circuit for itself, and closes its contacts 225 to complete obvious multiple locking circuits for the relays R210, R230 and R260. At its contacts 222, the relay R220 opens a point in an incomplete holding circuit for the coin control relay R100. At its contacts 224, the relay R220 opens a-point in one of the available paths for impressing negative coin refund potential upon the two sides of the line 10. At its contacts 223, the relay R220 prepares a path for impressing positive coin collect potential upon the two conductors of the line 10. At its contacts 226, the relay R220 further prepares the operating circuit for the coincontrol relay R100. 7 I

After the call is answered at the substation B to cause the operation of the back-bridge relay R310 in the manner explained above, this relay is rendered non-responsive to further reversals in the direction of current flow over the loop circuit extending between the adapter circuit 25 and the connector 16. Accordingly, therelease of the connection at the called substation B is without effect. When, however,-the party using the paystation A hangs up tointerrupt the call ing loop circuit, the relay R restores to defrom the adapter circuit; 25 to the connector I 0.

The reoperation oi the digit relay R300 is without efl'ect. Coincident with the release oi the line relay RI50, the control relay R240 closes its contacts 2 to reprepare the operating circuit for the magnet 213. When the loop circuit extending from the connector It to the adapter circuit 25 is opened, this connector, the finderselector link I4, I 5. and the line circuits I2 and I3 are all released in the usual manner. -Inci'-v dentto the release of the connector I3, the control conductor 313 is disconnected from ground to deenergize the upper winding of the back- ,bridge' relay R3I0, to remove ground potential from the private conductor 312 and to deenergize the lower winding of the relay RI40.. The lower winding of the relay R3I0-and the lower winding of the relay R320 are deenerglzed when the loop circuit connecting the adapter circuit 25 and the connector I is initially opened. The relay R320,

in restoring, closes its contacts 322 further to prepare the above-mentioned paths for impressing coin collect and refund potentials upon the two sides of the line I0. The relay R3I0, in restoring, opens its contacts 3| 1 to interrupt'the operating circuit for the transfer relay'R220, and closes its contacts 3I5 to complete the prepared operating circuit for the coin control relay RI00,

this circuit extending from ground by way of 1 the contacts 3I3,'320 and I33, and the winding of RI 00 to battery. At its contacts 3I3, the relay R3I0 also recompletes the above-traced circuit ror energizing the magnet 218.

when the relay R200 restores shortly following the release of the line relay RI50, it opens its contacts 203 to interrupt the initially completed locking circuits for the relays R2I0, R230 and R250. At its contacts 204'and 205, the relay R200 opens the initially completed operating circuit, and then completes a locking circuit for the digit relay R300, the latter circuit extending from ground by way 01' the contacts I53, 205 and 233 and the winding of'R30ll to battery. At its contacts 205, the relay R200 completes an obvious circuit for energizing the release magnet 213, whereby the wiper 211 is restored to its normal position in the usual manner. Incident to the return movement of this wiper the oil-normal sprin s 203 are disengaged to deenergize the release magnet 210.

As indicated above, the coin control relay RI00 is, energized in response to the release of the back-bridge relay R3I0. Upon operating, the relay RI00 closes its contacts I05 to impress ground potential upon the control conductor 313, whereby the lower winding of the incoming call relay RI40 is energized,. the upper winding of the back-bridge relay R3I0 is energized through the resistor 3I0, and the private conductor 312 is marked with guarding ground potential through the upper winding of the incoming call relay RI43. It will be understood that neither of the two relays RI 40 and R3I0 operate when their respective lower and upper windings are energized over the indicated circuits. At its contacts I05, the relay RI00 completes obvious multiple locking circuits for the three relays R2I0,

R230 and'R260. At its contacts I02 and I04, the relay RI00 completes the above-mentioned path for impressing positive coin collect potential upon the two sides of the line I0. This path extends from the positive terminal 01' the coin collect source I02a by way of the resistor I620,

the conductor I02, the contacts III and 223, the winding of R330 and the contacts 322, I02 and I04 to the conductors oi' the line I0. This potential, which is of a value of approximately 110 6 volts, as. applied to the positive side or the line I0 energizes the windings of the polarized magnet 38 in a direction such that the associated coin mechanism is operated to discharge the deposited coin into the collection box of the pay- 10 station; It will be noted that the relay R330 is energized in series with the windings oi the coin control magnet 30. Accordingly this relay operates and closes its contacts 33I to complete an,

obvious circuit for energizing the coin control relay R340. The latter relay, upon operating,

closes its contacts 342 to complete a holding circuit through the contacts 22I for the transfer relay R220. In this regard it is pointed out that the three relays RI00, R330 and R340, upon sequentially operating in response to the release 01' the back-bridge re1ayR3I0, close the abovedescribed circuit through the contacts 342 and 22l before the slow-to-release relay R220 can restore in response to the release of the relay R320.

According1y the relay R220 is maintained in its operated position so long as the coin collect potential is applied to the two sides of the line I0. Incident to the operation of the magnet to collect the deposited coin, the coin mechanism of the paystation operates to open the contact springs 33 and to close the contact springs 40, whereby the series-connected windings of the magnet 30 and the relay R330 are deenergized. It will be understood, therefore, that if the coin 5 -collecting operation is effected with sufllcient speed, the-coin control relay R340 will not be operated. Accordingly, no holding circuit will be provided for the transfer relay R220 and this relay will restore to initiate the release of the 4.0. adapter circuit 25 immediately after the coin collecting operation is completed. On the other hand, if -the operation of the coin mechanism is somewhat sluggish, such that the collecting operation is delayed, the relay R330 operates to provide a holding circuit for the transfer relay R220 in the manner explained above. In operating, this relay also closes its contacts 343 to condition the delayed alarm circuit 351 for operation. At its contacts 3, the relay R340 prepares a path for impressing a signal voltage upon the negative talking conductor '310. At its con- I tacts 345, the relay R340 opens a point in certain operating and locking circuits described below. At its contacts 344, the relay R340 prepares a'circuit including the pickup lead 300 for energizing the pickup relay R350. This pickup leadis arranged to be periodically connected to ground through the contacts of a constantly operating timing device 350a provided in the common equipment 23. Accordingly, ii the coin collecting operation is not carried out within a reasonable time interval to cause the release of the relays R330 and R340, the relay R350 is energized in a circuit which includes the contacts354 and 6 344, the pickup lead 350 and the contacts of the timing device 3300.. In operating, this relay first locks to ground over a path including the contacts 353, I39, 226 and 3I3, and then opens its contacts 354 to interrupt its operating circuit as traced above. At its contacts 352, the relay R350 completes an obvious circuit for energizing the alarm signal lamp 356. At its contacts 3;", the relay R350 completes a circuit for transmitting ground pulses from the pulsing device 35m 7 through the series-connected windings oi the two relay R320 and R340. Each time the relay R320 is energized over the lead 36I by the pulsing device 36Ia, it opens its contacts 322 .to deenergize the coin control relay R330 and the windings of the magnet 38. Each time the relay R320 is deenergized at the end of a ground pulse applied to the lead 36I, it restores and closes its contacts 322 to again energize the series-connected windings of the relay R330 and the magnet 38. The intermittent operation and release of the two relays R320 and R330 continues until the coin collecting operation is completed at the paystation A, at which time the contact springs 39 are disengaged to interrupt the circuit for energizing the series-connected windings of the magnet 36 and the coin control relay R330. The relay R330 now restores and opens its contacts 33] to deenergize the upper winding of the coin control relay R340. When the pulsing lead- 3.6I is thereafter disconnected from ground by the pulsing device 36Ia, the lower winding of the relay R340 and the upper winding of the relay R320 are also deenergized. The relay R340 now restores and opens its contacts 342 to deenergize the transfer relay R220. At its contacts 343, the relay R340 opens the prepared delayed alarm circuit 351. At its contacts 344, the relay R340 opens another point in the operating circuit for the pickup relay R350. Before the next ground pulse is applied to the pulsing lead 36 I, the transfer relay R220 restores and opens its contacts 226 to deenergize the coin control relay RI and the pickup relay R350. At its contacts 22I, the relay R220 opens another point in its locking circuit as traced above. At its contacts 225, the rela R220 opens the multiple locking circuits for the relays R2I0, R230 and R260. Atits contacts 224, the relay R220 completes apath through the contacts I2I, 322, I02 and I04. and the winding of the coin control rela R330 for impressing negative coin refund potential upon the two sides of the line I0. This operation is without effect. At its contacts 223, the relay R220 opens a point in the above-traced path for impressing positive coin collect potential upon the two sides of the line I 0. The relay R350, upon restoring, opens its contacts 35I to prevent further energization of the two relays R320 and R340. At its contacts 352, the relay R350 deenergizes the signal lamp 356. At its contacts 353, the relay R350 opens another point in its locking circuit as traced above. At its contacts 354, the rela R3-5l reprepares its operating circuit.

The relay RI00, upon restoring, opens its contacts I05 to disconnect the private conductor 312 from ground and thus render the line I0 accessible to the various connectors having access thereto. At these contacts the relay RI00 also deenergizes the lower winding of the relay RI40 and the upper winding of the back-bridge relay R3I0. ,At its contacts I06, the relay RI00 deenergizes the three relays R2I0, R230 and R260, causing all of these relays to restore. In releasing, the relay R260 opens its contacts 266 to deenergize the operating magnet 216 of the digit counting switch 215, whereby the wiper 211 is advanced one step from its illustrated normal position. In response to this operation the onnormal springs 200 are closed to again energize the release magnet 219. This magnet, in operating, attracts its associated holding pawl permitting the wiper 211 to again be restored to normal,- at which time the elf-normal springs 280 are opened to deenergize the release magnet. The coin relay R230, upon restoring, opens its of the hold relay R200.

contacts 236 to deenergize the digit relay R300, and closes its contacts 231 to re-energize the coin control relay RI00 in a circuit which includes the contacts I53, 205 and 305. The relay RI00, upon reoperating, recloses its contacts I06 to again energize the control relay R250 in a circuit which also includes the contacts 304 and 265. The relay R260 now reoperates, and recloses the operating circuit for the magnet 213. Shortly following these operations the relay R300 restores and opens its contacts 305 to cause the sequential release of the relay RI 00 and the control relay R260. The latter relay, upon restoring, opens its contacts 266 to deenergize the magnet 218, whereby the wiper 211 is again advanced one step from its normal position. Incident to this operation, the oil-normal springs 260 are reclosed to again energize the release 'magnet 216, whereby the wiper 211 is returned to its normal position. Incident to the release of this wiper, the off-normal springs 280 are opened to again deenergize the release magnet 219. Following the operations just described, all of the equipment included in the adapter circuit 25 is restored to normal and the line I0 is marked as idle in the bank contacts of the connectors to which it is accessible' In the event the called line II is busy at the time it is selected by the connector I6, or the call as extended to the substation B is not answered; the control equipment of the connector does not function to reverse the direction of current flow over the loop circuit extending from this switch to the adapter circuit 25. Accordingly, the back-bridge relay R3I0 remains in its restored position. With this relay restored, no circuit isprovided for energizing the transfer relay R220. Accordingly, when the calling party disconnects to cause the release of the line relay RI50, the operation'of the digit relay R300 and the release of the hold relay R200 in the order named, the locking circuits for the relays R2I0, R230 and R260 areopened at the contacts 203 Upon restoring, the relay R200 closes its contacts 206 to cause the .re-

lease of the digit counting switch 215 in the exact manner explained above. The release of the pulse cut-oil" relay R2I0 is without effect. The relay R260, upon restoring, opens its contacts 266 to interrupt the operating circuit for the magnet 218. The relay R230, upon restoring, opens its contacts 236 to deenergize the digit relay R300, and closes its contacts 231 to energize the coin control relay RI00 in a circuit which incl1 des the contacts I53, 205, 231 and 305. In operating, the relay RI00 closes its contacts I06 to again energize the control relay R260 over a circuit which includes the contacts 304 and 265. In reoperating, the relay R260 again closes its contacts 266 to energize the magnet 218. In

operating, the relay R260 also locks to ground I I over a path including its contacts 264 and the contacts I06. The remaining circuit switching operations performed by this relay are of no effect.

1 In operating, the coin control relay RI00 also completes a path for impressing negative coin refund potential upon the two sides of the line 1 I0, it being noted in this regard that the transto actuate the coin control mechanism ina manner such that the deposited coin is dumped into the coin refund chute of the paystation equipment. Incident to the operation of this mechanism the contacts 39 are opened to denergize the magnet 38 and the coin control relay R330.

During the'time interval required for the coin refunding operation to be eflected, the relay R330 is energized and closes its contacts 33I to energize the coin control relay R340. In the present casethe relay R340, upon closing its contacts 342, completes a locking circuit for the coin control relay RI rather than the previously traced locking circuit for the transfer relay R220. More specifically, the completed locking circuit extends from ground by way of the contacts 342 and 222, and the winding of RI00 tobattery. It is noted that this locking circuit is completed at the contacts 342 before the slow-to-release coin control relay RI00 can restore in response to the release of the slow-to-release digit relay R300, which latter operation occurs shortly following the restoration of the coin relay R230. From this point on the manner in which the coin control relays R330, R340 and R350 and the back-bridge relay R320 operate in the event the coin refunding operation is not promptly completed, is exactly the same as set forth above with reference to the manner in which a coin collecting operation is efiected. From this explanation it will be recalled that the coin control relay R340 is only released when the coin refunding operation is fully completed. Upon restoring, the relay R340 opens its contacts 342 to deenergize the relays RI00 and R350. The relay RI00, upon restoring, opens its contacts I09 to deenergize the relay R200. The latter relay,. upon restoring,

. opens its contacts 283150 deenergize the magnet 219, whereby the wiper 211 is advanced one step from its illustrated normal position. Incident to this oil-normal movement of the wiper 211, the oil-normal springs 290 are closed to energize the release magnet 219. When this magnet is energized the wiper 211 is returned to normal and the oil-normal springs 280 are opened to deenergize the magnet 219. Thus the adapter circuit 25 is fully restored to normal.

Free service calls As indicated previously, if the paystation A is to be used in making free service calls without coin deposits, the Y strap normally shunting the pulsing springs of the calling device 32 is omitted from the wiring of the paystation equipment, the Y strap of the adapter circuit 25 is omitted, and the W straps are provided iii-this circuit. In such case, the digit counting switch 215 cooperating with the pulse cut-oil relay R2I0 is utilized to prevent calls other than free service calls from being successfully completed without coin deposits. The only limitation on the use of the digit counting switch 215 for this purpose, is that the directory numbers assigned to the subscriber lines directly accessible to the paystation A shall have two more digits than the directory numbers assigned to the free service trunks. For example, if all subscriber lines terminating in the exchange are assigned fourdigit directory numbers, the free service information and toll trunks, for example, may be assigned either one digit or two digit directory numbers. If the free service trunks are assigned one digit directory numbers the lead 232 is connected to the third contact of the contact set 210. Accordingly, when the single di i designating a group of free service trunks is dialed into the adapter circuit 25, the wiper 211 is only that the call must be routed to the toll operator switchboard I9. It may be assumed further that the finder-selector link I4, I5 and the reverse battery repeater I8 are utilized in extending the connection to this operator switchboard. Incident to the operation of the selector I5 to seize the repeater I8 at the end of the single digit designating the group of trunks extending to the switchboard'l9, the loop circuit is extended from the adapter circuit 25 to this repeater and the controlequipment of the repeater functions to transmit a call signal to the operator attending the switchboard I9. When the call is answered at this switchboard the control equipment of the repeater I8 functions to reverse the direction of current flow through the series-connected lower windings of the two relays R3I0 and R320. In response to this current reversal, the relay R3I0 closes its contacts 3" to complete the prepared operating circuit -for the switching relay RI30,

' this circuit extending from ground by way of the fer relay R220.

closes its contacts 225 to complete multiple lockcontacts 3 and 2I4, and the upper winding of RI30 to battery. The other circuit switching operations performed by the relay R3I0 are exactly the same as described above.

In operating the relay RI30 locks to ground over a path which includes the contacts I31 and 3". At its'contacts I38, the relay RI30 completes an alternative circuit for energizing the pulse cut-off relay R2I0, this circuit extending from ground by way of the contacts 203, 303, 345, I38 and 235, and the upper winding of R2I0 to battery. It will be noted that if a coin has been deposited at the paystation A such that the coin relay R230 is operated, the circuit just traced is held open at the contacts 235. At its contacts I39, the relay RI30, upon operating, opens a point in one of the previously traced operating circuits for the coin control relay RI00. At its contacts I3I and- I34, the relay RI30 opens two points in the calling loop circuit extending to the paystation A, thereby to deenergize the line relay Rl50 and the control relay R240. At its contacts I3I and I35, the relay RI30 extends the calling loop circuit to the repeater I8 free of any attachments.

Assuming first that no coin is'deposited at the paystation A prior to the origination of the free service call, the pulse cut-off relay R2I0 is energized and operates incident to the operation of the switching relay RI30, in the manner explained above. Upon operating, the relay R2I0 locks to ground through the contacts 2| 2 and 203, and closes its contacts 2I3 to complete the previously traced operating circuit for the trans- In operating, the relay R220 ing circuits for the relays R2I0 and R260. At its contacts 223, the relay R220 prepares the previously traced path fo impressing positive coin collect potential upon the two sides of the line I0. At its contacts 22I, the relay R220 prepares the previously traced locking circuit for itself. Coincident with the operation of the three relays Rl30, R2I0 and R220, the line relay RI50 restores and opens its contacts I52 to deenergize the hold relay R200. At its contacts I53, the relay RI 50 completes the operating circuit for the digit relay R300. When the hold relay R200 restores shortly thereafter, the coin control relay RI is energized in the above-traced circuit including the contacts I53, 205, 231 and 305. In operating, the relay RI00 completes the previously traced path for impressing coin collect potential upon the two sides of the line I0. In this case, however, since no coin has been deposited at the paystation A, the windings of the magnet 38 and the coin control relay R330 are not energized. Shortly following the operation of the relay RI 00 the digit relay R300 releases and opens its contacts 305 to deenergize the relay RI00. The latter relay, upon restoring, recloses the loop circuit extending to the repeater I3 and disconnects the conductors of the line I0 from the coin collect lead I62. It will be noted that under the conditions assumed above, the relays R2I0 and R220 are operated in the adapter circuit 25 after the call is answered at the toll operator switchboard I9. With the relays Rl30, R2I0 and R220 operated, the adapter circuit 25 is conditioned to impress coin collect potential upon the conductors of the line I0 incident to the release of the connection.

In the event a coin is deposited at the paystation A prior to the extension of the connection to the toll operator switchboard I9 in the manner explained above, the coin relay R230 is operated in the adapter circuit 25. In such case the switching relay Rl30, upon operating in response to the operation of the backbridge relay R3l0, only prepares the operating circuit for the pulse cut-off relay R2I0, this circuit being held open at the contacts 235. When the line relay RI50 and the hold relay R200 sequentially restore in response to operation of the switching relay RI30, the operating circuit for the digit relay R300 is completed at the contacts I53 incident to the release of the line relay, and the locking circuits for the relays R230 and R260 are opened at the contacts 203 incidentto the release of the hold relay R200. Upon restoring, the relay R200 also opens its contacts 204 to deenergize the digit relay R300, and closes its contacts 205 to prepare the above-traced operating circuit for the coin control relay RI00. At its contacts 203, the relay R200 also opens the previously traced alternative operating circuit for the pulse cut-off relay R2I0. The circuit-for energizing the digit relay R300 is opened at the contacts 236 and that for energizing the relay RI00 is completed at the contacts 231 incident to the release of the coin relay R230. In operating, the relay RI00 closes its contacts I06 to complete the operating circuit for the control relay R260, which latter relay, upon operating, locks to ground through its contacts 264 and closes its contacts 266 to reprepare the operating circuit for the magnet 218. At its contacts I 05, the relay RI00 completes a multiple holding circuit for the back-bridge relay R3l0 and a multiple path for impressing ground potential upon the private conductor 312. At its contacts IM and I03, the relay RI00 interrupts the loop circuit extending from the paystation A to the repeater I8. At its contacts I02 and I04, the relay RI00 completes the above-described path for impressing negative refund potential upon the two sides of the line I0, whereby the windings of the magnet 30 and the coin control relay R330 are energized. When thus energized the magnet 38 causes the coin control mechanism to refund the deposited coin in the manner previously explained. The relay R330, upon operating, closes its contacts 33I to energize the relay R340. The latter relay, in operating, closes its contacts 342 to complete the previously traced locking circuit for the coin control relay RI00. At its contacts 345, the relay R340 opens the previously traced alternative operating circuit for the pulse cut-of! relay R2I0. Shortly following the operation of the coin-control relay R340, the digit relay R300 restores and closes its contacts 303 to reprepare the above-traced alternative operating circuit for the pulse cutoff relay R2I0. From this point on the manner in which the relays R320, R330, R340 and R350 operate in the event the refunding of the deposited coin is not immediately completed, is exactly the same as described above. From this explanation it will be recalled that after the coin refunding operation is completed the relays R330 and R340 are sequentially deenergized. In releasing, the relay R340 opens its contacts 342 to deenergize the coin control relay RI00 andthe relay R350, if operated, and closes its contacts 345 to complete the above-traced alternative operating circuit for the pulse cut-off relay R2I0. The latter relay, in operating, closes 'a circuit through the contacts 2I3 and 3I1 for energizing the transfer relay R220. Upon operating, the relay R220 closes its contacts 225 to complete multiple locking circuits for the two relays R2I0 and R260. Shortly following the operation of the two relays R2I0 and R220 the coin control relay RI00 restores. In releasing, this relay opens its contacts I06 to interrupt the multiple locking circuits fOr the two relays R2I0 and R260. At its contacts. I05, the relay RI00 opens the multiple locking circuit for the back-bridge relay R3l0 and one of the paths over which ground potential is impressed upon the private conductor 312. At its contacts I02 and I04, the relay RI00 disconnects the two conductors of the line I0 from the negative potential refund lead I6I. At its contacts IM and I03, the relay RI00 recompletes the loop circuit extending between the paystation A and the repeater I8. It will be noted that, following the release of the coin control relay RI00 to perform the functions just described, only the relays Rl30, R2I0, R220, R260 and R3l0 are operated in the adapte eircuit 25. With the two relays R2 I0 and R220 operated, the adapter circuit is conditioned to impress positive coin collect potential upon the two conductors of the line I0 incident to the release of the connection.

After the connection has been answered at the toll operator switchboard I9, it may be extended to the desired substation at a distant exchange in a manner well understood in the art, and the operator handling the call may instruct the calling party either before the desired connection is completed or at some time prior to the release thereof, as to the amount of the charge for the call. In this regard it will be understood that when coin deposits totaling the amount of the charge of the call are deposited at the paystation A, the usual audible signals are transmitted over the established talking circuit to the cord circuit of the operator handling the call at the switchboard I9, whereby the operator is informed of the value of the deposited coins.

In the event the cord circuit in use at the toll operator switchboard I9 and the repeaters ascoin refund relay RIIO.

sociated with the trunks extending to this,

made in the repeaters associated with the trunks extending to the available operator switchboard facilities and in the cord circuits provided at these positions, for directly controlling the paystation coin mechanism at any time while a connection thereto is set up. Yiccordingly, provisions including the coin control connector 22 and a number of other similar connectors are provided in the illustrated system for indirectly controlling the coin mechanisms provided at the paystation. In'the case under consideration if the operator handling the call at the toll operator switchboard I9 desires to refund the deposited coins, she may do so by seizing the toll selector 20 and dialing the digits of the directory number designating the coin refund conductor I04. When the digits of this number are dialed a control connectionmay be routed through the toll selector 20 and the coin connector 22, for

example, to the conductor I64. If this conductor tests idle in the connector 22, the control equipment of the connector functions to impress ground potential thereon, thereby to energize the In operating, the relay RI I0 short-circuits its lower winding over a path including the contacts 3 and 345. At its contacts N3, the relay RIIO also completes an alternative circuit for energizing the upper winding of the pulse cut-off relay R2I0, this circuit extending from ground by wayof the contacts .225 and 303, the lower winding of RI I0, the contacts I I3, I30 and 235 and the upper winding of -R2I 0 to battery. At its contacts II I, the relay RIIO opens the previously traced path for impressing positive coin collect potential upon the conductors of the line I0. At its contacts II2, the relay RIIO prepares a path for impressing negative coin refund potential upon the conductorsv of the line I0. At its contacts N5, the

relay RI I0 prepares a circuit for transmitting a refund tone signal current over the connection to the cord circuit of the operator handling the call at the switchboard I9.

At its contacts II4, the relay RIIO completes an obvious circuit for energizing the coin con-- trol relay RI 00. The latter relay, upon operating, closes its contacts I06 to complete multiple locking circuits for the two relays R2I0 and R260, and closes its contacts I to complete a multiple locking circuit for the back-bridge relay R3I0 and a multiple path for impressing guarding ground potential upon the private conductor 312. At its contacts IM and I03, the relay RI00 opens the loop circuit extending between the paystation A and the repeater I8. At its contacts I02 and I04, the relay RI00 connects the conductors of the line I0 to the negative potential refund lead IOI over a path which now includes the contacts 322, the winding of R330, the contacts 223 and H2. When this path is completed the magnet 38 actuates the associated coin mechanism i to refund the coin or coins deposited at the paystation A in the manner previously explained. Also when this path is completed the relays R330 and R340 are caused sequentially to operate in the manner pointed out above. At its contacts I, the relay R340 completes the above-mentioned signaling circuit. This circuit may partially be traced as extending from the tone transformer I 66a by way of the conductor I00, the contacts Hi, the condenser 355 and the contacts '3 to the negative talking conductor 3 10. In this regard it will be understood that the two tone transformers I854: and I800 are connected to sources of alternating. current having different frequencies. Accordingly, when the abovetraced signaling circuit is completed, a distinctive tone is produced by the receiver-of the operator cord circuit in use at the switchboard It to inform the operator handling the call that a coin refunding operation is in progress. At its contacts 342, the relay R340 completes the previously traced locking circuit for the transfer relay R220. At its contacts 345, the relay R340 opens the above-traced path short-circuiting the lower winding of the coin refund relay RI I0, permitting this winding to be energized in series with the upper winding of the pulse cut-ofl relay R2I0 in a circuit which includes the contacts 235, I38, H3, 303 and 225. Following the operation of the two relays R330 and R340, the coin refunding operation proceeds under the control of these two relays, the back-bridge relay R320, and the relay R350 in the exact manner previously explained. In this regard it will be understood that when the coin refunding operation -is completed, the relays R330 and R340 are sequentially deenergized and restore. In releasing, the relay R340 opens its contacts 342 to interrupt the multiple holding circuit forthe transfer relay R220, and recloses its contacts 345 to again short-circuit the lower winding of the coin refund relay RI I0. In the event the control connection as routed through the toll selector 20 and the coin control connector 22 is released at the toll operator switchboard I9 prior to the completion of the coin refunding operation, such that the coin refund lead I64 is disconnected from ground, the relay RI I0 is deenergized and restores incident to the release of the relay R340. In restoring, this relay opens its contacts II4 to deenergize the coin control relay RI 00. The latter relay, upon restoring, opens the path for impressing negative coin control potential upon the two conductors of the line I0, recloses the loop circuit to the repeater I0, and opens the multiple locking circuits for the relays R2I0, R260 and R3I 0. Incident to the release of the two relays RIIO and I for the coin refund relay RI l0. The provision of this circuit is of importance since it prevents the coin refunding operation from being interrupted before it is completed due to the premature release of the control connection as set up through the toll selector 20 and the coin control connector 22.

In' the event the operator handling the call at the switchboard I9 desires to effect a coin collecting operation while the call is in progress, she may do so by extending a connection through the toll selector 20 and the coin control connector 22 to the coin collect conductor I63. In this regard it will be understood that separate directory numbers are assigned to the conductors I53 and I34 so that an operator at the switchboard I9 may seize either of these two leads by dialing the appropriate directory number. Assuming that the toll selector 20 and the connector 22 are used to select the conductor I33, the control equipment of the connector 22, in operating to connect this conductor to ground, completes an obvious circuit for energizing the upper winding of the coin collect relay RI 20. In operating, this relay shortcircuits its lower winding through the contacts I23 and 345, closes its contacts I25 to prepare a path for transmitting a coin collect signal to the operator handling the call, and closes its contacts I24 to complete an obvious operating circuit for the coin control relay RIM. The relay RIM, up-

on operating, performs the functions described above, but in this case completes a path through the contacts I02, I04, III, 322 and 223, and the winding of the coin control relay R330 for impressing positive coin collect potential upon the two conductors of the line I0, whereby a coin collecting operation is initiated. The relay R340, upon operating in response to the operation of the relay R330, opens its contacts 345 to interrupt the path short-circuiting the lower winding of the relay RI20, permitting this winding to be energized in series with the upper winding of the pulse cut-off relay R2I0. At its contacts 34I, the relay R340 completes a circuit through the condenser 355 and the contacts I25 for transmitting collect tone signal current from the transformer I65 through the receiver of the operator cord circuit in use by the operator handling the call at the switchboard I9. From this point on the manner in which the coin collecting operation is completed and the relays R330, R340, RI 20 and RIM are deenergized, is exactly the same as explained above.

When the connection as extended to the toll operator switchboard I9 is released at the paystation A, disconnect supervision is given to the operator handling the call at this switchboard, but no circ'uit switching operations are performed in the adapter circuit 25. Since the conductors of the line III are switched through to thereverse battery repeater I3, the operator handling the call may re-ring the paystation without disturbing the setting of the relays in the adapter circuit 25, providing re-ring facilities are incorporated in her cord circuit and in the reverse battery repeater I8.

When the operator handling the call at the switchboard I3 takes down the connection, the reverse battery repeater I8 is released. During the release of this repeater, the link I4, I is released and the control conductor 313 is disconnected from ground to cause the sequential release of the relays R3I0 and RI30. RI30, upon restoring, closes its contacts I33 to complete one of the previously traced operating circuits for the coin control relay RIM. Assuming that uncollected coins remain in the coin chutes of the paystation equipment, a coin collecting operation is started in response to the operation of the coin control relay RIM, which operation proceeds in the exact manner explained above. It is noted in this regard, that the two relays R330 and R340 are operated at the beginning of the coin collecting operation and remain operated until it is completed. When these two relays restore, the other operated relays of the adapter circuit 25 are released in theexact manner explained above with reference to therelease of the adapter circuit upon the termination oi! a local call. On the other hand, if no coins are to be collected at the paystation A when the connection is released, no circuit is available for energizing the coin control relay R330 when the coin control relay operates. Accordingly, no locking circuit is provided for the transfer relay R220 and this relay restores shortly following the release of the switching relay RI30. In releasing, the relay R220 opens its contacts 220 to deeperglze the coin control relay RIM. The latter relay, upon restoring, initiates the release of the adapter circuit 25 in a manner clearly apparent from the preceding explanation.

Incoming local calls Incoming local calls to the paystation A are handled by the regular connectors of the automatic switching equipment. Thus a call originating at the substation B, for example, and intended for the substation A, may be routed to this station through the finder-selector I4, I5 and the connector I5 under the directive control of the calling party at the substation B. At the end of the dialing operation and when the wipers of the connector I6 are positioned on the contacts individual to the line I0, the usual busy test is made by the control equipment of the connector for the purpose of determining the idle or busy In this regard it will be understood from the preceding explanacondition of the selected line.

tion that when the adapter circuit 25 is occupied with an outgoing call, guarding ground potential is impressed upon the private conductor 312 through the upper winding of the relay RI40 and the contacts I42b of the busy key I42. If the private conductor 312 is connected to groundover this path at the time the line I0 is selected by the connector I6, the busy test relay of this connector operates in the usual manner to return a busy signal to the calling subscriber at the substation E. In this connection it will be noted that the busy test relay of the connector is energized in a circuit which extends from the grounded control lead 313 through the upper winding of the The relay relay RI40 and the contacts I42b-to the private conductor 312. The current flow in this winding is in opposition to the sustained current flow through the lower winding of the relay RI 40 and, accordingly, this relay does not operate. On the other hand, if the line I0 is idle at the time it is selected, the private conductor 312 is marked with negative battery potential over a path which includes the contacts I42b, the two windings of the relay RI40 and the resistor I43. When this potential is found by the test wiper of the connector I6, the connector automatically switches into its ringing position in the usual manner. Incident to this operation the private conductor 312 is connected to ground in the connector I5 to provide a circuit for energizing the two windings of the relay RI40 in series. also connected through the upper winding of the a relay RI40 to the control conductor 313, thereby This ground path is its contacts-B810 prepare the common portionof the previously traced locking circuits for the coin refund and collect relays RIIO and Rl20. At its contacts I 38, the relay RI30 also prepares the previously traced operating circuit for the pulse cut-'ofl relay R2I0. At its contacts I39, the relay RI30 opens a point in one of the previously traced operating circuits for the coin control relay RI00. At its contacts I32 and I35, the relay RI 39 connects the conductors of the line I to the talking conductors 310 and 3' free of all attachments, thereby to provide a circuit over which ringing current may be transmitted through the ringer 36 provided at the paystation A.

The relay R220, upon operating, closes its contacts 22l to prepare a locking circuit for itself, and opens its contacts 224 to interrupt one of the previously traced paths for impressing coin control potentials upon the conductors of the line I0. At its contacts 223, the relay R220 prepares the other path over'which coin control potentials may be applied to the conductors of the line I0.

.At its contacts 225, the relay R220 prepares the previously traced locking circuits for the two relays R2I0 and R230, as well as the operating and locking circuits for the relay R260. At its contacts 225, the relay R220 also completes the pre-- pared operating circuit for the pulse cut-01f relay 'R2I0. The relay R2I0 now operates and locks to ground through the contacts 2 I 2 and 225. The remaining switching operations performed bythis relay are of no eilect at this time.

Following the operation of the four relays Rl30, RIQII, R2I0 and R220, no further switching operations occur in the adapter circuit 25 until the connection as set up between the substationB and the paystation A is released. In this regard it will be understood that when the calling and called parties disconnect, the automatic switchtraln including the connector I6, the selector l5 and the finder II are released in an entirely conventional manner. Incident to the release of the connector IS the private conductor 312 is disconnected from ground therein, thereby to deenerize the relay RI40 and the cut-01f relay of the line circuit I2. In releasing, the relay RI 40 opens its contacts III to deenergize the switching relay RI30. The latter relay, in restoring, closes its contacts I39 to complete a circuit through the contacts 226 and 3 I6 for energizing the coin control relay RI00. In the present case the operation of the relay RI00 is without effect since no coins are on deposit at the paystation A. Shortly following the release of the switchin relay RI30, the transfer relay R220 restores and opens its contacts 226 to deenergize the coin control relay RI 00. The relay RI00, upon restoring, opens its contacts I06 to deenergize the relay R2I0. Following the release of the latter relay the adapter circuit 25 is fully restored to normal.

Incoming toll calls In extending toll calls to the paystation A, the operator attending the switchboard I9 may use the toll selector 20 and the toll connector 2|,

for example. Assuming that these two switches of this circuit by the toll connector 2| are exactly-the same as occur when this circuit is seized through a local connector. It will be understood,

therefore, that after a connection is set up to the paystation A from the toll operator switchboard I9, the relays RI30, Rl40, R2I0 and R220 are operated in the adapter circuit 25. With these re- R330 to the collect conductor I62.

lays operated, the operator handling the call at the switchboard I9 may selectively control the coin refund and coin collect relays RIM and Rl20 through a second toil selector and an available coin control connector, either to effect coin refunding or coin collecting operations at the paystation A. This type of control has particular utility in the handling of delayed toll call connections, since it permits an operator at the switchboard I9 to locate a subscriber desired by a calling party at the paystation A,.and then 'recall the calling party at this paystation without losing control of the coin mechanism thereat. In this regard it will be understood that if the coin refund relay RI I0, for example, is seized through the coin control connector 22, for example, from the toll operator switchboard I9 after the connection to the'payst'ation A is established, this relay will operate the cause the sequential operation of the relays RIM, R330 and R340, assuming that coins are on deposit at the paystation A, which are to be refounded. It will also be understood that the relay R330 is energized in series with the windings of the magnet 38 over the previously traced coin refund control circuit. The mannerv in which the coin refunding operation is carried out under the control of the relays R320, R330, R340 and R350 will be clearly apparent from the preceding explanation, it being understood from this explanation that after the refundin operation is completed only the relays RI30, RI40, R2I0 and R220 remain operated in the-adapter circuit 25.

In the event the coin collect relay RI20 is seized through the coin control connector 22, for example, from the toll operator switchboard I9, a coin collecting operation occurs in the exact manner previously explained, it being understood in this regard that the only difference in the operation of the adapter circuit 25, as between the operation of the coin refund relay RI I0 and the coin collect relay RI20, resides in the fact that in one case the conductors of the line I0 are connected through the winding of the relay R330 to r the negative refund conductor I BI, and in the other case to the positive collect conductor I62. In either case, the four relays RI30, RI40, R2) and R220 are the only relays which remain operated in the adapter circuit 25 after the coin control operation is completed.

With the four indicated relays operated in the adapter circuit 25 at the time the toll connection as set up between the switchboard I9 and the paystation A is released, a coin collecting operation is automatically performed, providing coins are on deposit'at the paystation A. Thus when the two relays RIM and RI30 sequentially restore incident to the release of the connection, the above-described circuit including the contacts I39, 226 and 3| 6 is completed for energizing the coin control relay RI00. This relay, in operat- 'ing, connects the conductors of the line I0 through the winding of the coin control relay Hence, if coins are on deposit at the paystation A a coin collection operation is carried out in the exact manner explained above. Afterthis. operation is completed, the adapter circuit is released. On the other hand, if no coins are on deposit at this paystation the relay R330 remains in its restored position to permit the release of the coin control relay RI00 shortly following the restoration of the switching relay RI". Upon restorin the coin control relay RIM opens its contacts I06 to deenergize the pulse cut-oil relay R2i0. Following the release of the latter relay the adapter circuit 25 is fully restored to normal.

If for any reason it is desired to out the paystation A out of service the busy key I42 is operated to its oft-normal position wherein the contact springs 14% thereof are opened and the contact springs |42a thereof are closed, and the key I44 is operated to its open-circuit position to interrupt one side of the line It! extending to the paystation A. With the contacts of the key I44 disengaged, obviously no control may be exercised over the adapter circuit 25 from the paystation A. With the busy key I42 occupying its off-normal position the private conductor 312 is connected directly to ground to prevent seizure of the adapter circuit 25 through any of the connectors having access thereto. Thus this circuit cannot be seized either on incoming or outgoing calls.

As indicated previously, the coin control relay R340 is arranged to control, through its contacts 343, a delayed alarm circuit 351. This circuit is preferably S arranged that an alarm indication is not produced thereby until the relay R340 has been operated for a period exceeding a predetermined time interval. In this regard it will be understood that when an alarm indication is produced by the circuit 351 it indicates that an abnormal condition exists in the equipment associated with one of the paystation lines. This alarm indication is supplemented by the signal lamp 356 which is individual to the adapter circuit 25, and when energized indicates the source of the alarm indication, i. e., the particular equipment in which the abnormal condition exists.

While one embodiment of the invention has been disclosed, it will be understood that various modifications may be made therein which are within the true spirit and scope of the invention.

What is claimed is:

1. In a telephone system, a paystation including a mechanism for controlling the collection and refunding of coins or the like, an operator position, means for setting up a connection between said paystation and said operator position, and means comprising an automatic switch separate from said connection and controllable from said operator position for controlling said mechanism so long as said connection is not released.

2. In a telephone system, a paystation including means for collecting coins or the like, an operator position, means for setting up a connection between said paystation and said operator position, and means omprising an automatic switch separate from said connection and controllable from said operator position for operating said collecting means so long as said connection is not released.

3. In a telephone system, a paystation including a mechanism for controlling the collection and refunding of coins or the like, an operator position, means for setting up a connection between saidpaystation and said operator position, and means comprising an automatic switch separate from said connection and controllable from said operator position for selectively controlling said mechanism to collect or refund coins at any time after said connection is extended to said operator position and prior to its release.

4. In a telephone system, a paystation including means for refunding coins or the like, an

operator position, means for setting up a connection between said paystation and said operator position, and means comprising an automatic switch separate from said connection and controllable from said operator position for operating said coin collecting means so long as said connection is not released.

5. In a telephone system, a plurality of paystations each including a mechanism for controlling the collection and refunding of coins or the like, an operator position, means for setting up connections between said operator, position and said stations, an automatic switch separate from the means utilized in establishing any one of said connections and controllable from said operator position and operative to different settings individually designating .the collection and refunding of coins deposited at different ones of said paystations, and means selectively controlled in accordance with the settings imparted to said switch for selectively controlling said mechanisms to collect and refund coins.

6. In a telephone system, a plurality of paystations each including a mechanism for controlling the collection of coins or the like, an operator position, means for setting up connections between said operator position and said stations, an automatic switch separate from the means utilized in establishing any one of said connections and controllable from said operator position and operative to different settings individually designating the collection of coins deposited at different ones of said stations, and means selectively controlled in accordance with the settings imparted to said switch for selectively operating said mechanisms.

7. In a telephone system, a plurality of paystations each including a mechanism for controlling the refunding of coins or the like, an operator 'position, means for setting up connections between said operator position and said stations, an automatic switch separate from the means utilized in establishing. any one of said connections and controllable from said operator position and operative to difierent settings individually designating the refunding of coins deposited at different ones of said stations, and means selectively controlled in accordance with the settings imparted to said switch for selectively operating said mechanisms.

8. In a telephone system, a paystation line,

- an adapter circuit terminating said line and including means for selectively impressing coin collect and coin refund potentials upon at least one of the conductors of said line, an operator position, means including said circuit for setting up a connection between said. line and said operator position, and means including an automatic switch separate from said connection and controllable from said operator position for controlling said first-named means.

9. In a telephone system, a plurality of paystation lines, adapter circuits individually terminating said lines and each including means for selectively impressing coin collect and coin refund potentials upon at least one of the conductors of the respective associated line, an operator position, means including said circuits for setting up connections between said. lines and said operator position, and means including an automatic switch separate from said connecting means and controllable from said operator position for selectively controlling said first-named means. 7

10. In a telephone system, a plurality of paystation lines, adapter circuits individually terminating said lines, an operator position, means including said circuit for setting up connections between said lines and said operator position, and an automatic switch separate from the means utilized in establishing any one of said connecand an automatic switch separate from the means utilized in establishing any one of said connections and directively controllable from said operator position and having two diflerent settings for each' of said circuits, each of said circuits including means responsive to the operation of thereto for impressing a coin refund potential upon at least one of the conductors of the associated line and means responsive to the operation of said switch to the other setting corresaid switch to one of the settings corresponding spending thereto for impressing a coin collect potential upon at least one conductor ofthe associated line. a

12. In a paystation control circuit which is adapted to be included in a connection established between a paystation line and another line, a path for impressing coin control potential upon at least oneconductor of said line, a relay adapted to be controlled over, a connection which is entirely separate from said first-named connection, and? means responsive to the operation of said relay for completing. said path. a

13. In a' paystation control circuit which is adapted to be included in a connection established between a paystation line and another line, paths for impressing coin refund and coin collect potentials upon at least one conductor of said line,

a pair of relays which are adapted to be selectively controlled over a connection which is entirely separate from said first-named connection, and means responsive to the operation of one of said relaysv for completing one of said paths and responsive to the operation of the other of said relays for completing the other of said paths.

14. In a paystation control circuit which is adapted to be included in a connection established between a paystation line and another line,

a path for impressing coin control potential upon at least one conductor of said line, a relay adapted to be controlled over a connection which is entirely separate from said first-named connection, means responsive to the operation of said relay for completing said path and forlocking said relay operated, and means controlled over said line for releasing said relay.

ing said other relay operated, and means revertively controlled over said line by the coin control mechanism of said paystation for releasing the operated one of said relays. Y

16. In a telephone system, a paystation including a mechanism for controlling the disposal of coins or the like, a line extending to said station, an operator position, means including a paystation control circuit for setting up a connection between said line and said operator position, a coin control circuit forcontrolling said mechanism, said coin control circuit extending between said paystation and said paystation control circuit and including at least one conductor of said line, means for setting up a second connection between said operator position and said paystation control circuit before said first-named connection is released, and means controlled over said second connection for completing said coin control circuit.

. 17. In a telephone system, a paystation including a mechanism for controlling the disposal of coins or the like, a line extending to said station, an operator position, means including a paystation control circuit for setting up a connection between said line and said operator position, a coin control circuit for controlling said mechanism, said coin control circuit extending between said paystation and said paystation control circuit and including at least one conductor of said line, means for setting up'a second connection between said operator position and said paystation control circuit, agrelay operated in response to the-"6ompletion-rof said second connection, means responsive to the operation of said relay for completing said coin control circuit and for locking said relaypperated independently of said second connection," and means responsive to the operation of said mechanism for releasing said relay and for opening said coin control circuit in said paystation control circuit. 1

18. In a telephone system, a paystation including a mechanism for controlling the collection of coins or the like, a line extending to said paystation, an operator position, means including a payand collect potentials may be impressed upon at 15. In a paystation control circuit which is I adapted to be included in a connection established between a paystation line and another line, paths for impressing coin refund and coin collect potentials upon at least one conductor of said line, a pair of relays which are adapted to be selectively controlled over a connection which is entirely separate from, said first-named connecleast one conductor of said line to effect the operation of said mechanism and a pair-of relays respectively operative to eflect the completion of said paths, and means including a second connection set up between said circuit and said operator position for selectively operating said relays.

19. In a telephone system, a paystation including a mechanism for controlling the collection of coins or the like, a line extending to said station,

an operator position, means including a paystation control circuit for setting up a connection between said line and said operator position, said circuit including paths over which coin refund and collect potentials may be impressed upon at least one conductor of said line to- 'eflect the operation of said mechanism, means for setting up either of two diflerent control connections between said circuit and said operator position, a pair of relays included in said circuit and respectively operated when said control connections are set up, means responsive to the operation of one of said relays for completing one of said paths and for locking said one relay operated and responsive to the operation of the other of said relays for completing the other of said paths and for locking said other relay operated, and means responsive to the operation of said mechanism for releasing the operated one of. said relays.

20. In a telephone system, a paystation including a mechanism for controlling the disposal of coins or the like, a line extending to said station, an operator position, means including a paystation control circuit for setting up a connection between said line and said operator position, a coin control circuit for controlling said mechanism, said coin control circuit extending between said paystation and said paystation control circuit and including at least one conductor of said line, means for setting up a second connection between said operator position and said paystation control circuit before said first-named connection is released, and means controlled over said second connection for completing said .coin control circuit and for transmitting a signal over said first-named connection to said operator position.

21. In a telephone system, a paystation including a mechanism for controlling the collection of coins or the like, a line extending to said paystation, an operator position, means including a paystation control circuit for setting up a connection between said line and said operator position, said circuit including paths over which coin refund and collect potentials may be impressed upon at least one conductor of said line to effect the operation of said mechanism, means for settin up a second connection between said operator position and said paystation control'circuit, and means controlled over said second connection for selectively completing said paths and for transmitting a signal over said first-named connection to said operator position which indicates the path that is completed.

22. In a telephone system, a paystation line, an adapter circuit terminating said line and including paths for impressing coin collect and coin refund potentials upon at least one of the conductors of said line. an operator position, means including said adapter circuit for extending a connection from said line to said operator position, and means included in said circuit and operative in response to the answering of the call at said operator position for completing one of said paths in said circuit.

23. In a telephone system, a paystation line, an adapter circuit terminating said line and including paths for impressing coin collect and coil refund potentials upon at least one of the conductors of said line, an operator position, means including said adapter circuit for extending a connection from said line to said operator position, means included in said circuit and operative in response to the answering of the call at said operator position for completing said coin refund path, and means included in said circuit and operative in response to the release of the connection at said operator position for completing said coin collect path.

24. In a telephone system, a paystation line, an adapter circuit terminating said line and including paths for impressing coin collect and coin refund potentials upon at least one of the conductors of said line, an operator position, means including said adapter circuit for extending a connection from said line to said operator position, means included in said circuit and operative in response to the answering of the call of said operator position for completing said coin refund path, and means including an automatic switch separate from said connection and controllable from said operator position for selectively completing said paths.

25. In a telephone system, a paystation line, an adapter circuit terminating said line and including paths for impressing coin collect and coin refund potentials upon at least one of the conductors of said line, an operator position, means including said adapter circuit for extending a connection from said line to said operator position, means included in said circuit and operative in response to the answering of the call at said operator position for completing said coin refund path, means including an automatic'switch separate from said connection and controllable from said operator position for selectively completing said paths, and means included in said circuit and operative in response to the release of the connection at said operator position for completing said coin collect path.

26. In a telephone system, a paystation line, an

adapter circuit including a bridge provided with reactive elements for transmitting signal currents between said line and a called line, an operator position, means including said circuit and a succeeding automatic switch trainfor extending a connection from said paystation to said operator position, and means included in said circuit for excluding said bridgefrom a connection set up between said paystation and a succeeding switch train incident to the operation of the switch train to extend the connection to said operator position.

27. In a telephone system, a paystation line, an adapter circuit including a bridge provided with reactive elements for transmitting signal currents between said line and a called subscriber line, an operator position, means including said circuit and a succeeding automatic switch train for extending a connection from said paystation to a. called subscriber line or to said operator position, means included in said circuit for excluding said bridge from a connection set up between said paystation and a succeeding switch train incident to the operation of the switch train to ex-* tend a connection to said operator position, and

means included in said circuit for preventing the operation of'said last-named means in setting up connections between said paystation line and subscriber lines.

28. In a telephone system, a paystation line, an adapter circuit including a path for impressing a coin control potential upon at least' one of the conductors of said line and a bridge provided with reactive elements for transmitting signal currents between said line and a called subscriber line, an operator position, means includ 29. In a telephone system, a paystation line, an

adapter circuit including a p th for impressing a coin control potential upon at least one Of the conductors of said line and a bridge provided with reactive elements for transmitting signal currents between said line and a called subscriber line, an operator position, means including said circult and a succeeding automatic switch train for extending a connection from said paystation to said operator position or-to a subscriber line, means included in said circuit for automatically excluding said bridge from a connection extended to said operator position from said line, means included in said circuit for preventing the operation of said last-named means in setting up connections between said paystation line and subscriber lines, andmeans operative in response to the answering of a call routedirom said paystation line to said operator position for completing said path.

- 30. In a paystation line adapter circuit which is adapted for use in setting up connections between a paystation line and subscriber lines or trunks, a bridge provided with reactive elements coupling the two ends of said circuit to provide a signal transmission channel therebetween, and means responsive to the extension of a connection through said circuit to a trunk for excluding said bridge from the connection. 31. In a paystation line adapter circuit which is adapted for use in setting up connections between apaystation line and subscriber lines or aascyao tion, means including said circuit and a succeeding automatic switch train for extending a connection from said paystation to said operator position or to a subscriber line, and means controlled by said digit counting device for preventing said connection from being extended to said subscriber line unless said coin relay is operated.

35. In a telephone system, a paystation, a line extending to said paystation, an adapter circuit terminating said line and including an impulsing relay for directing automatic switch operations, a digit counting device controlled by said relay and a coin relay operative to register the deposit of a coin at said paystation, an operator position, means including said circuit and a succeeding automatic switch train for extending a connection from said'paystation to said operator position or to a subscriber line, means controlled by said digit counting device for preventing said trunks, a bridge provided with reactive elements coupling the two ends of said circuit to provide a signal transmission channel therebetween,

. an impulsing relay for'directing automatic switch operations and a digit counting device controlled by said relay, an operator position, means including said circuit and a succeeding automatic switch train controlled by said relay for extending a connection from said paystation to a subscriber line or to said operator position, means controlled by said digit counting device for preventing a connection from being extendedthrough said autoinatic switch train to a subscriber line unless a coin has been deposited at said paystation, means included in said circuit for automatically excluding said bridge from a connection set up between said paystation and said operator position, and means controlled by said digit counting device for preventing the operation of said last-named means in setting up a connection between said paystation and a subscriber line.

3'3. In a, telephone system, a paystation; an adapter circuit including an impulsing relay for directing automatic switch operations and a digit counting device controlled by said' relay, an operator position, means including said circuit and a succeeding automatic switch traincontrolled by said relay for extending a connection from said paystation to said operator position or to a subscriber line, and means controlled by said digit counting device for preventing said connecvtion from being extended to said subscriber line unless a coin is deposited at said paystation.

34. In a'telephone system, a paystation, a line extending to said paystation, an adapter circuit terminating said line and including an impulsing relay for directing automatic switch operations, a digit counting device controlled by said relay and a coin relay operative to register the deposit of a coin at said paystation, an operator posiimpulsing relay from directing the operation of said switch train beyond a predetermined switching stage, and means controlled by said coin relay for rendering said last-named means ineflfective.

36. In a circuit which is adapted for use in set-' ting up connections between a paystation and subscriber lines or trunks, an impulsing relay for directing the operation of succeeding automatic switches, and means including a digit counting devicecontrolled by said relay forrendering said relay ineifective to control succeeding automatic switches beyond a predetermined switching stage in the event a coin is not deposited at said paystation.

37. In a circuit which is adapted for use in setting up connections between a paystation and subscriber lines or trunks, an impulsing relay for directing the operation of succeeding automatic switches, a coin relay operative to register the o deposit of a coin at said paystation, a digit counting device controlled by said impulsing relay, means controlled by said digit counting device for rendering said impulsing relay ineifective to control succeeding automatic switches beyond a predetermined switching stage, and means controlled by said coin relay for rendering said lastnamed means ineffective.

38. In a circuit which is adapted for use in setting up connections involving a paystation line, a path for impressing a coin control potential upon at least one conductor of said line, a pickup lead, a pickup relay, means responsive to the completion of said path for connecting said pickup relay to be energized over said pickup lead, and means responsive to the operation of said pickup relay for intermittently opening said path.

39. In a circuit which is adapted for use in setting up connections involvinga paystation line,

a path for impressing a coin control potential upon at least one conductor of said line, a pickup lead, a pickup relay, means responsive to the completion of said path for connecting said pickup relay to be energized over said pickup lead, a source of current pulses,'a relay operative to open said path, and means responsive to the operation of said pickup relay for connecting said lastnamed relay to be controlled from said'source of current pulses.

40. In a telephone system which includes a paystation and a line extending to said paystation, a circuit incuding at least one conductor 01 said line for controlling the disposition of coins deposited at said paystation, a pickup lead, a pickup relay, means for completing said circuit, means responsive to the completion of said circuit

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