US1540310A - Testing system - Google Patents
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- US1540310A US1540310A US624105A US62410523A US1540310A US 1540310 A US1540310 A US 1540310A US 624105 A US624105 A US 624105A US 62410523 A US62410523 A US 62410523A US 1540310 A US1540310 A US 1540310A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/20—Testing circuits or apparatus; Circuits or apparatus for detecting, indicating, or signalling faults or troubles
Definitions
- This invention relates to testing systems and more particularly to systems for testing and adjusting apparatus used in signaling over telephone line circuits.
- signaling current of one character suitable for transmission over the line from a distant station It is sometimes desirable to employ signaling current of one character suitable for transmission over the line from a distant station and to provide at the receiving station a relay or other means responsive there to for translating such signaling current into current suitable for operating the signaling apparatus thereat.
- the translating means must be responsive to incoming current of the proper character, but unresponsive to current of other character, which may be impressed on the line, such, for example, as impulses caused by a calling subscriber attempting to recall the operator by working the switchhook of his telephone up and down, it is desirable to provide means for readily testing such translating means under such conditions in order that any necessary adjustments may be made to insure its nonresponse to such improper currents but its response to currents of the proper cha 'acter.
- an automatic telephone impulse sender of the usual type is employed for generating the current impulses which simulate the current impulses to which it is desired the translating means shall not respond.
- electromagnetic means are provided and so arranged in association with the impulse sender that a fewer number of impulses are transmitted to the translating means than the number of times the inipulse sender makes and breaks its pulsing contact.
- A represents, what is commonly known as, a composite ringer set which may be connected between a transmission line and an exchange switchboard by means of cords and plugs C and G which are adapted to be inserted in jacks J and J, so that the conductors 1 and 2 will connect with the line and conductors 3 and 4 with the switchboard.
- Conductors 1 and 3 are normally connected by means of conductor 7 and conductors 2 and 4 by means of conductor 8 through the normal contacts and armatures of relays 5 and 6.
- relays 11 and 12 Bridged across the conductors 7 and 8 through the retardation coils 9 and 10 are the relays 11 and 12, relay 11 being adjusted to respond to ringing currentof a frequency similar to that of the current of the switchboard, which in practice may be 20 cycles and relay 12 being adjusted to respond only to ringing current having a frequency similar to that of the ringing current transmitted over the transmission line, which in practice, might be 135 cycles.
- ringing current sent out from the switchboard over conductorsS and 4 will cause relay 11 to operate, but relay 12 will not operate as it is adjusted to respond to current of a different frequency and ringing current coming in over the line to conductors 1 and 2 will cause the relay 12 to operate but will not afiect relay 11 as it is adjusted to respond to current of a lower frequency.
- relay 12 causes the release of relay 13 which in turn causes relay 6 to operate to disconnect the ringer set from the switchboard conductors and to ap ply 20 cycle ringing current thereto, and the operation of relay 11 causes the operation of relay 5 which disconnects the ringer set from the line and applies cycle ringing current thereto from the source lat.
- the operation of relay l1 also closes a circuit for the' operation of relay which in sures the continued energization of relay 13 during the ringing interval.
- the apparatus and circuits to the left and, below the dottedv line designated as B represents the testing system of the, present invention which is adapted to be connected to the com.- posite ringer A by means of the, jacks J and J and the cord-s C and C Connected across the springs 16 and 17 of the jacks J 2 and J, respectively, is a. relay 18 responsive to. 20 cycle ringing current) which controls through its armature and alternate contact.
- a signaling device such as a bell 19.
- a signaling device such as a bell 19.
- apparatus for generating current impulses which simulate the switchhook impulses before mentioned which comprises a transformer 23', sources of. current 2% and 25, and an, impulse senderi22 of well.
- impulses that is, to supply impulses simulating. those generated by the sub scribefis switchhook when moved up and down in an attempt to signal the operator, jacks J and J, are connectedby means of cordC and J and J by means of cord (3,; Plug: P is inserted intojaclt J, and the dial (not shown) of the impulse sender 22 is ro tated to the right and released in the well known manner.
- Relay 32 in operating connects the output circuit of the simulated switching trunk
- relay 26 operatesand transfers the circuit of the pulsing contact, from the upper normal contact of relay 26 to the winding of relay 2? which circuit may be traced from pulsing contact spring EMA, tip contacts ofjplug P and jack J upper armature and alternate contact of relay, 26., con ductor 36, lower normal contact 37, of relay 29, eonductor 38, upper normal contact 39 of relay 28 and winding of relay 2? toground; Relay however, does not operate at this time as the pulsing contact 3a is open.
- Relay 26- in operatingalso closed a, circuit from grounded battery 24-through the upe per winding of retardation coil; -10, lower alternatecontact 41 of relay 26, upper normal contact 42 of; relay 43, winding 4 of transformer 23, upper alternate contact of relay 32,- conductor. 46, spring 20 of. jack J tip conductor of cord C, tip spring of jack J, conductor 1, upper, normal contact ofrelay 5, conductor, 7, retardation coil 9, winding of relay 12, conductor 8-, lower normal contact of relay conductor 2, ring spring of aclt J ring conductor of cordC spring 21 of jack J conductor 47, armature and lower alternate contact of relay. 3.2, winding 48 of transformer 23-, mal contact of. relay 43, and. lower winding of retardation coil 1-0 to ground; This causes a surge of current to flow in the circuit just traced and causes a current pulse in relay 12 which tends to energize the relay;
- relay 2'? operates in the circuit which may be traced from grounded battery 31 winding of relay 32.
- Relay 2? inoperating closes a circuit for relay 28 which may be traced lower nora from grounded battery 31, winding of relay 32, conductor 33, sleeve contacts of J, and
- Relay 27 in operating closes at its lower alternate contact a circuit through the windings 50 and 51 of the transformer 23, battery 25, and relay 52 which causes a surge of current to be induced in the windings 44 and 48 of the transformer 23 which iiows over the circuit before traced to the composite ringer and causes another energizing pulse in the wind-V ings of relay 12.
- Relay 52 in operating closes a circuit through relay 43 which may be traced from grounded battery, winding of relay 43, conductor and upper alternate contact of relay 52 to ground.
- Relay 43 in operating opens at its upper and lower normal contacts the circuit for battery 24, before traced, thus causing a third surge of current in the winding of relay 12.
- relay 28 On the second break of the pulsing con tact 34, relay 28 operates as the short circuit around this relay is opened by the breaking of this contact but relay 27 is held operated as the energizing circuit for relay 28 is completed through the winding of relay 27.
- Relay 28 in operating transfers the pulsing contact circuit from the winding of relay 27 to the winding of relay 29 which circuit may be traced from spring 34A of sender 22, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower normal contact 37 of relay 29, upper alternate contact of relay 28, and winding of relay 29 to ground.
- relay 29 On the next make of the pulsing contact relay 29 operates in a circuit which may be traced from grounded battery 31, winding of relay 32, conductor 33, sleeve contacts of J, and P, shunt contact 30 of sender 22, pulsing contact 34, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower normal contact 37 of relay 29, conductor 38 upper alternate contact of relay 28, winding of relay 29 to ground.
- Relay 29 in operating opens the circuit for the windings of relay 27 and 28 at its upper normal contact.
- Relay 29 in operating also closes its lower alternate contact 53, thus preventing the relay from releasing when relay 28 is deenergized.
- Relay 29 in closing its lower alternate contact 53 establishes a direct energizing circuit from pulsing contact 34, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower alternate contact 53 of relay 29 and winding of relay 29 to ground.
- Relay 27 in releasing opens the circuit previously traced through the windings 50 and 51 of a transformer 23, battery 25 and relay 52 which causes a surge of current to be induced in the windings 44 and 48 which in turn causes a fourth pulse through the relay 12.
- On the opening of the pulsing contact after the second make relay 29 re leases.
- On the third make of the pulsing contact the chain of operations described for the first make of the pulsing contact is re peated. These four current pulses i.
- closure of the lower alternate contact of relay 26 closure of the lower alternate contact of relay 27 the operation of relay 43 and the opening of the lower alternate contact of relay 27, are approximately equivalent to the impulses caused by the average subscribers working of the switchhook in an attempt to signal the operatqr, when the subscribers telephone is connected through a toll switching trunk and a toll and circuit to a composite trunk line.
- a testing system comprising electro-responsive means to be tested, means for generating and transmitting electrical impulses simulating those generated by the operation of the switchhook in a subscribers telephone set when it is connected through a toll switching trunk and a toll cord circuit with a line, switching means for connecting said generating means with said electro-responsive means, and means for indicating the response of said electro-responsive means, said generating means comprising an au tomatic telephone impulse sender and a plurality of relays so arranged that a different numberot' impulses are transmitted to the 'translating device under test than the number of times the pulsing contact of the impulse sender is made and broken.
- systei in combination, a relay to be tested, a circuit having a transformer therein, a source of direct current, an impulse sender adapted to make and break a circuit a number of times when 01 erated and released, a plurality of relays controlled by said impulse sender and adapted to connect said currentsource to a Windof said transformer means for connecting said transtor. 181 to the winding of the relay to be tested and means for indicating the response of said relay.
- a relay to be tested a circuit comprising a transformer, a source of direct current, an
- impulse sender adapted to make and break a circuit a number of times when operated and released, a plurality of relays controlled by said impulse sender and adapted to (302% nect said direct current source to a Winding of said transformer. and also to disconnect said source from said transformer Winding to set up in the output of said trans former a series of impulses fewer in number than the number of? times the pulsing contact of the impulse sender is made and broken, means for connecting said transformer to the Winding of said relay to be d, and means for indicating: theresponse of said relay.
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Description
L. J. BOWNE TESTING SYSTEM Filed March 10, 1923 lnven/or: v Lang/"0rd J. Bow/7e Airy Patented June 2, 1925.
UNITED STATES PATENT o c LANGFORD J. BOWNE, OF HOWARD BEACH, NEVT YORK, ASSIGNOR TO WESTERN ELEC- TRIO COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.
TESTING SYSTElVL.
Application filed March 10, 1923. Serial No. 624,105.
To all whom it may concern:
Be it known that I, LANGFORD J. BOWNE, a citizen of the United States, residing at Howard Beach, in the county of Queens, State of New York, have invented certain new and useful Improvements in Testing Systems, of which the following is a full, clear, concise, and exact description.
This invention relates to testing systems and more particularly to systems for testing and adjusting apparatus used in signaling over telephone line circuits.
It is sometimes desirable to employ signaling current of one character suitable for transmission over the line from a distant station and to provide at the receiving station a relay or other means responsive there to for translating such signaling current into current suitable for operating the signaling apparatus thereat.
As the translating means must be responsive to incoming current of the proper character, but unresponsive to current of other character, which may be impressed on the line, such, for example, as impulses caused by a calling subscriber attempting to recall the operator by working the switchhook of his telephone up and down, it is desirable to provide means for readily testing such translating means under such conditions in order that any necessary adjustments may be made to insure its nonresponse to such improper currents but its response to currents of the proper cha 'acter.
It is an object of this invention to provide an improved method and means for testing translating means associated with telephone lines of the aforementioned character.
This object is attained in accordance with a feature of the invention by the provision of switching means so that such signaling apparatus or translating means may be dis connected from the line circuit and subjected to electrical conditions simulating those under which the translating means should not respond,'suitable signaling means being provided for indicating the operation of such translating means under these conditions. i
In accordance with another feature of the invention an automatic telephone impulse sender of the usual type is employed for generating the current impulses which simulate the current impulses to which it is desired the translating means shall not respond. 1
In accordance with still another feature of the invention, electromagnetic means are provided and so arranged in association with the impulse sender that a fewer number of impulses are transmitted to the translating means than the number of times the inipulse sender makes and breaks its pulsing contact. Other and further features will be apparent from the following description when read in connection with the accompanying drawing which shows diagrammatically one embodiment of the invention. Referring to the drawing the apparatus shown above and to the right of the dotted line and designated as A represents, what is commonly known as, a composite ringer set which may be connected between a transmission line and an exchange switchboard by means of cords and plugs C and G which are adapted to be inserted in jacks J and J, so that the conductors 1 and 2 will connect with the line and conductors 3 and 4 with the switchboard. Conductors 1 and 3are normally connected by means of conductor 7 and conductors 2 and 4 by means of conductor 8 through the normal contacts and armatures of relays 5 and 6.
Bridged across the conductors 7 and 8 through the retardation coils 9 and 10 are the relays 11 and 12, relay 11 being adjusted to respond to ringing currentof a frequency similar to that of the current of the switchboard, which in practice may be 20 cycles and relay 12 being adjusted to respond only to ringing current having a frequency similar to that of the ringing current transmitted over the transmission line, which in practice, might be 135 cycles. Accordingly, ringing current sent out from the switchboard over conductorsS and 4 will cause relay 11 to operate, but relay 12 will not operate as it is adjusted to respond to current of a different frequency and ringing current coming in over the line to conductors 1 and 2 will cause the relay 12 to operate but will not afiect relay 11 as it is adjusted to respond to current of a lower frequency.
The operation of relay 12 causes the release of relay 13 which in turn causes relay 6 to operate to disconnect the ringer set from the switchboard conductors and to ap ply 20 cycle ringing current thereto, and the operation of relay 11 causes the operation of relay 5 which disconnects the ringer set from the line and applies cycle ringing current thereto from the source lat. The operation of relay l1 also closes a circuit for the' operation of relay which in sures the continued energization of relay 13 during the ringing interval. I
It frequently happens that inductive disturbances or false current impulses are set up in composited trunk lines which tend to affect relay 12 and cause it tochatter sufficiently to allow relay 13 to release, thus causing afalsering to be transmittedtothe switchboard. It has been found that one of the principal causes ofthese false currents in systems of thischaracter is the genera tion of impulses by the operation of the switchhook of a subscribers .set in an attempt to signal the operator at the exchange when the subscribers set is connected through atoll switching trunk and a toll cord circuit with such a composited trunk line. It, therefore, is, apparent that the relay -12 should be .so adjusted that it will not respond to such false impulses but will respond to regular ringing impulses of. the selected frequency;
Again referring to the drawing, the apparatus and circuits to the left and, below the dottedv line designated as B represents the testing system of the, present invention which is adapted to be connected to the com.- posite ringer A by means of the, jacks J and J and the cord-s C and C Connected across the springs 16 and 17 of the jacks J 2 and J, respectively, is a. relay 18 responsive to. 20 cycle ringing current) which controls through its armature and alternate contact.
a signaling device such as a bell 19. Connectednacross the springs 20 and 21, of the jacks J, and J, is apparatus for generating current impulses which simulate the switchhook impulses before mentioned which comprises a transformer 23', sources of. current 2% and 25, and an, impulse senderi22 of well.
known type, which is adapted to be connected'with achain of relays 26, 27, 28 and 29 by means of plug P and jack J,.
The invention will bemore fully understood from the following description of 013% eration. To test the relay 12 against switchhool: impulses, that is, to supply impulses simulating. those generated by the sub scribefis switchhook when moved up and down in an attempt to signal the operator, jacks J and J, are connectedby means of cordC and J and J by means of cord (3,; Plug: P is inserted intojaclt J, and the dial (not shown) of the impulse sender 22 is ro tated to the right and released in the well known manner. On the closure ofthe shunt contact 5500f the sender relay 32 is operated in a circuit from grounded vba tter'y 31 winding of relay 32, conductor 33, sleeve contacts ofijack J and plug P, shunt contact and pulsing contact 34; of sender 22, tip contacts of plug P and jack J and upper armature and normal contact of relay 26 to ground. A circuit is also prepared at this time for the operation of relay 26 from grounded battery 31, relay 32, conductor 33,.sleev'e con tacts of jack J and plug P, shunt contact 30', ring contacts of P and J, and winding of relay, 2:6 to ground. Relay 26, however, does not operate at this time because it is short circuited by its upper normal con tact and thepulsiug contact 34.
with the line. side of the composite ringer set A over conductors 4:6 and 47, jacks J and J and cords G andC On thefirst break of,- the pulsing contact ofsender 2, relay 26 operatesand transfers the circuit of the pulsing contact, from the upper normal contact of relay 26 to the winding of relay 2? which circuit may be traced from pulsing contact spring EMA, tip contacts ofjplug P and jack J upper armature and alternate contact of relay, 26., con ductor 36, lower normal contact 37, of relay 29, eonductor 38, upper normal contact 39 of relay 28 and winding of relay 2? toground; Relay however, does not operate at this time as the pulsing contact 3a is open. Relay 26- in operatingalso closed a, circuit from grounded battery 24-through the upe per winding of retardation coil; -10, lower alternatecontact 41 of relay 26, upper normal contact 42 of; relay 43, winding 4 of transformer 23, upper alternate contact of relay 32,- conductor. 46, spring 20 of. jack J tip conductor of cord C, tip spring of jack J, conductor 1, upper, normal contact ofrelay 5, conductor, 7, retardation coil 9, winding of relay 12, conductor 8-, lower normal contact of relay conductor 2, ring spring of aclt J ring conductor of cordC spring 21 of jack J conductor 47, armature and lower alternate contact of relay. 3.2, winding 48 of transformer 23-, mal contact of. relay 43, and. lower winding of retardation coil 1-0 to ground; This causes a surge of current to flow in the circuit just traced and causes a current pulse in relay 12 which tends to energize the relay;
On the first make of. the pulsing contact- 34 after the first break, relay 2'? operates in the circuit which may be traced from grounded battery 31 winding of relay 32. conductor, 33, sleeve contacts of J, and, P, shunt contact 30 of sender 22, pulsing contact 34L, tip contacts of P and J upper alternate contact of relay 26, conduct'OlV 36, lower normal contact 37 of; relay 29, conductor 38, upper normal contact 39 of relay 28 and winding of relay 2? to ground. Relay 2? inoperating closes a circuit for relay 28 which may be traced lower nora from grounded battery 31, winding of relay 32, conductor 33, sleeve contacts of J, and
I, shunt contact J sender 22, ring contacts of P and .L, conductor 49, upper normal contact of relay 29, winding of relay 28, upper alternate contact of relay 27 winding of relay 27 to ground. Relay 28, however, does not operate at this time as it is shunted by the pulsing contact 34. Relay 27 in operating closes at its lower alternate contact a circuit through the windings 50 and 51 of the transformer 23, battery 25, and relay 52 which causes a surge of current to be induced in the windings 44 and 48 of the transformer 23 which iiows over the circuit before traced to the composite ringer and causes another energizing pulse in the wind-V ings of relay 12. Relay 52 in operating closes a circuit through relay 43 which may be traced from grounded battery, winding of relay 43, conductor and upper alternate contact of relay 52 to ground. Relay 43 in operating opens at its upper and lower normal contacts the circuit for battery 24, before traced, thus causing a third surge of current in the winding of relay 12.
On the second break of the pulsing con tact 34, relay 28 operates as the short circuit around this relay is opened by the breaking of this contact but relay 27 is held operated as the energizing circuit for relay 28 is completed through the winding of relay 27. Relay 28 in operating transfers the pulsing contact circuit from the winding of relay 27 to the winding of relay 29 which circuit may be traced from spring 34A of sender 22, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower normal contact 37 of relay 29, upper alternate contact of relay 28, and winding of relay 29 to ground. On the next make of the pulsing contact relay 29 operates in a circuit which may be traced from grounded battery 31, winding of relay 32, conductor 33, sleeve contacts of J, and P, shunt contact 30 of sender 22, pulsing contact 34, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower normal contact 37 of relay 29, conductor 38 upper alternate contact of relay 28, winding of relay 29 to ground. Relay 29 in operating opens the circuit for the windings of relay 27 and 28 at its upper normal contact. Relay 29 in operating also closes its lower alternate contact 53, thus preventing the relay from releasing when relay 28 is deenergized. Relay 29 in closing its lower alternate contact 53 establishes a direct energizing circuit from pulsing contact 34, tip contacts of P and J upper alternate contact of relay 26, conductor 36, lower alternate contact 53 of relay 29 and winding of relay 29 to ground. Relay 27 in releasing opens the circuit previously traced through the windings 50 and 51 of a transformer 23, battery 25 and relay 52 which causes a surge of current to be induced in the windings 44 and 48 which in turn causes a fourth pulse through the relay 12. On the opening of the pulsing contact after the second make relay 29 re leases. On the third make of the pulsing contact the chain of operations described for the first make of the pulsing contact is re peated. These four current pulses i. e., on the closure of the lower alternate contact of relay 26, closure of the lower alternate contact of relay 27 the operation of relay 43 and the opening of the lower alternate contact of relay 27, are approximately equivalent to the impulses caused by the average subscribers working of the switchhook in an attempt to signal the operatqr, when the subscribers telephone is connected through a toll switching trunk and a toll and circuit to a composite trunk line.
When the dial (not shown) of sender 22 is operated to its extreme position and released, it makes and breaks the pulsing con tact 34 ten times thus causing the chain of operations just described to function five times and sending five sets of impulses into relay 12 which may be sufficient if the relay is not properly adjusted to cause its armature to vibrate and allow its controlled relay 13 to release thus causing the energization of relay 6 and the connecting of ringing current from the source 54 to the conductors 3 and 4 which are connected by means of cords O and O, to the springs 16 and 17 across which is connected the relay 18 which is responsive to such ringing current, thus causing the actuation of the signaling device 19 which signifies to the test operator that the relay 12 has operated and therefore the composite ringer set is in need of adjustment.
When the dial returns to normal the shunt contact 30 opens and releases all relays thus restoring the equipment to normal.
It will be obvious that the general principles herein disclosed may be embodied in many other organizations quite different from those illustrated, without departing from the spirit of the invention as defined by the following claims.
What is claimed is:
1. A testing system comprising electro-responsive means to be tested, means for generating and transmitting electrical impulses simulating those generated by the operation of the switchhook in a subscribers telephone set when it is connected through a toll switching trunk and a toll cord circuit with a line, switching means for connecting said generating means with said electro-responsive means, and means for indicating the response of said electro-responsive means, said generating means comprising an au tomatic telephone impulse sender and a plurality of relays so arranged that a different numberot' impulses are transmitted to the 'translating device under test than the number of times the pulsing contact of the impulse sender is made and broken.
2. In a testing: systei in combination, a relay to be tested, a circuit having a transformer therein, a source of direct current, an impulse sender adapted to make and break a circuit a number of times when 01 erated and released, a plurality of relays controlled by said impulse sender and adapted to connect said currentsource to a Windof said transformer means for connecting said transtor. 181 to the winding of the relay to be tested and means for indicating the response of said relay. i I
3. In a testing systenn'in combinatiom a relay to be tested, a circuit comprising a transformer, a source of direct current, an
impulse sender adapted to make and break a circuit a number of times when operated and released, a plurality of relays controlled by said impulse sender and adapted to (302% nect said direct current source to a Winding of said transformer. and also to disconnect said source from said transformer Winding to set up in the output of said trans former a series of impulses fewer in number than the number of? times the pulsing contact of the impulse sender is made and broken, means for connecting said transformer to the Winding of said relay to be d, and means for indicating: theresponse of said relay.
In witness whereof I hereunto subscribe my name this 8th day of March A. D.,
LANGFORD J. BOVNE.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US624105A US1540310A (en) | 1923-03-10 | 1923-03-10 | Testing system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US624105A US1540310A (en) | 1923-03-10 | 1923-03-10 | Testing system |
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US1540310A true US1540310A (en) | 1925-06-02 |
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US624105A Expired - Lifetime US1540310A (en) | 1923-03-10 | 1923-03-10 | Testing system |
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1923
- 1923-03-10 US US624105A patent/US1540310A/en not_active Expired - Lifetime
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