US656703A - Telephone system. - Google Patents

Telephone system. Download PDF

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US656703A
US656703A US72217299A US1899722172A US656703A US 656703 A US656703 A US 656703A US 72217299 A US72217299 A US 72217299A US 1899722172 A US1899722172 A US 1899722172A US 656703 A US656703 A US 656703A
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circuit
station
wire
line
telephone
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US72217299A
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Frank Glenn Rugh
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WILSON W ADAMS
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WILSON W ADAMS
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/68Circuit arrangements for preventing eavesdropping
    • H04M1/70Lock-out or secrecy arrangements in party-line systems

Definitions

  • FRANK GLENN RUGI'I OF BRIAR BLUFF, ILLINOIS, ASSIGNOR OF ONE- FOURTH TO WILSON IV.
  • ADAMS OF ATKINSON, ILLINOIS.
  • This invention relates to a telephone system, by the use of which any one station or subscriber on a line containing three or more instruments may be called up without the call being rung at the remainingstations, which latter being cut out of the calling circuit will remain quiet.
  • the object of my invention therefore is to overcome this defect and soimprove the service that on lines 'includingthree or more instruments in circuit any subscriber on the line may call any other subscriber without informing others of the fact.
  • This object I accomplish by such combination and adj ustment of the parts and the advantageous con-' nections at the instruments that normally all the telephones except one, usually the last called, are cut out of the line.
  • Each station is provided with a disk D,mounted on a shaft adapted to be rotated by suit able means in the direction of the arrow and controlled in its rotation by a lever L, drawn in one direction by an electromagnet M and in the opposite direction by a spring N.
  • the main-line Wire 19 is connected at each station to the electromagnet M and also to a normallyclosed circuit-breaker or key K, the latter being used to open and close the circuit when the disks D are to' be rotatedfor calling up a station by closing the circuit through line-wire a at that station.
  • On the face of each disk D is a series of numerals, each numeral representing a station on the line.
  • each disk at its respective stationnumber Fixed to each disk at its respective stationnumber is a pin 19, adapted to close connection between a pair of spring-fingers S or other circuit-closing device in the main line a.
  • the circuit-closing fingers S are so arranged with relation to the numerals on their approximate disks that when any number say 1 at one station is beneath the circuitclosing fingers the same number on the disks at all the other stations will be in similar position.
  • the circuit through the main line 1), ground E, and battery X is causing all the leversL to vibrate and the severaldisks to move synchronously in the directionof the arrow.
  • a wire 0 which is connected to the magnet of a sig nal-bell B, and thence passes to and is attached to a contact point or stop 6 beneath the telephone-hook H, which connects therewith when the receiver is hung on said hook.
  • a wire h passes from the hook H to ground.
  • a shunt-wire d at each station is connected to the spring-finger S and passes thence to a magneto-generator G, being attached to a normally-open contact at, which is automatically closed in the well-known manner when the generator is operated.
  • a wire at connects the armature of the generator G to the telephone-hook H.
  • the ordinary telephone-hook H is raised by means of a spring into contact with two contact points or stops fand-g when the telephone or receiver is removed; but when it is hung thereon it (the hook) is drawn down into contact with the stop 6, heretofore described.
  • a wire 11 passes to one end of the primary winding of an induction-coilI, and a wire a" connects one endof the secondary winding of the coil to the same stop f.
  • the opposite end of the primary winding of the induction-coil is connected by a wire 25 to a battery 00, transmitting-telephone T, and the stop g.
  • the other end of the secondary winding of the induction-coil is attached to a receivingtelephone R by means of a wire 1', which extends thence to the shunt-wire d, connected, as heretofore described, to the main-line wire (1.
  • Each transmitting-telephone is in an independent circuit formed by a battery 00, primary winding of the local induction-coil I, wire 1, stops f g, telephone-hook H, and Wire 25.
  • the receiving-telephone R is in the secondary circuit of.
  • the active induction-coils I the current of which passes from the coil by wire 1" through the receiver Rvto wire 01 and mainline wire a to station 3, thence by wires dand rof said station 3 througlnreceiver R to the secondary winding of coil I, wire 2', to stopf, telephone-hook H, which had been drawn into contact with stop f and 9 when the receiver R was removed, and wire it to ground, back to station 1 and by way of Wire h, telephonehook I-I, stop f, and wire t" to coil I.
  • the receivers R having been removed from their hooks H, the latter are drawn up by their springs, breaking the circuit through the bell at the stop 6 and closing the circuits through the transmitters T and receivers R by connecting the stops fa'nd g.
  • the circuit-closers S of all other instruments except at station 3 being open and no other bell than that at station 3 being sounded, the other subscribers on the line will not know that the line is being used. Hence they will not take their receivers off the hooks H.
  • the secondary circuit which contains the receivers R, is, as hereinbefore described, a ground-circuit; but by omitting the groundwire h and connecting each book H to the main-line wire I), as shown by the dotted lines L, a metallic circuit is formed.
  • the disk D on theface of which the various station-numbers are placed and to which the pin 19 is attached, is secured to a shaft D, (see Figs. 3 and 4,) adapted to be rotated by any suitable clock -mechanism.
  • An escapement-wheel D on the shaft D is engaged by pallets D on the arm L, to which an armature D is attached.
  • the lever L heretofore described, is moved in opposite directions or vibrated by the alternate action of the electromagnet M and spring N. Each movement of the lever L allows the escapement-wheel D to turn the distance of one tooth, which will gradually and intermittently bring the pinp on the disk D into position to close the circuit-closer S.
  • the modified form of my telephone system illustrated in Fig. 2 differs in some respects from the form shown in Fig. 1.
  • I use but one battery for all purposes-that is to say, for bringing a station onto the line a, ringing the bell, and
  • a circuit-changer O is introduced into the main-line circuit 1) at each station for shunting the current around the magnets M and through the signal-bell B.
  • Contact points or stops m n are so placed that when the receiver R is removed from the hook H a spring will lift the hook and bring the insulated plate into electrical connection with said contact-points m n. The same movement will close a circuit between the hook H and a contact-point 0.
  • the weight of the receiver when on the hook breaks connection with the contactpoints m, 'n, and 0 and lowers the hook into contact with the stop e.
  • the stops p g are by the same movement electrically connected by the insulated plate 70.
  • the circuits are as follows: To call up station 1 from station 3, the key K at station 3 is operated until the disk D indicates that the pin 19 at station 1 has closed the fingers of circuit-closer S.
  • the main-line circuit b is a closed circuit passing from battery X by wire I) to stop q beneath the hook H, insulated plate 70, stop 19, again on wire I), through the key K and circuit-changer O at station 3 to the main-line wire Z),which enters station 2, and, passing over a similar route therein, as in station 3, continues to station 1, where after again passing through the instrument in a similar manner it goes to ground and back to station 3.
  • the operator at station 3 presses his circuitchanger G into contact with point a shunting the current around the magnet M and by Way of wire a and main-line wire a to finger S of the circuit-closer at station 1 without passing through the instrument at station 2.
  • the current reaches station 1, it passes through the circuit-closer S to bell B by wire 0, thence to stop e,telephone-hook Hto ground and back to battery, causing bell B at station 1 to ring until the circuit-changer O at station 3 is released.
  • the finger has been removed from the circuit-changer G and the receivers taken from their hooks H, the said hooks are lifted immediately into contact with the points 122, n, and 0.
  • the primary circuit is from the batteryX by wires 1) 25 through transmitter to the primary winding of the induction-coil I at station 3, from whence it passes by wired to stop a, across the insulated platej to stop m, and by Wire 6 to mainline wire I), out of station 3 to stations 2 and l in succession, through which the circuit passes in a similar manner,as in station 3.
  • AE- ter passing through station 1 the circuit is completed through the ground to battery X.
  • the secondary circuit is readily traced from the secondary Winding of the induction-coil at station 3 through the receiver R by way of wire 4" to main-line wire a, running directly to station 1, thence through wire 0 at that station, receiver R, secondary winding of inductioncoil 1, wire e" to stop 0, thence over the hook H, wire it to ground, back to station 3, and by wire it, hook H, stop 0, and wire 71 to induction-coil I, from whence it started.
  • the advantage in this arrangement over that now in use consists in having one battery only to generate all the energy necessary for the entire line, thus doing away with local batteries and magneto-generators and bells at each station, an ordinary electric bell being substituted for the magneto-bell now in use.
  • the battery being at the central station or at one end, it can be cared for and kept in order more readily than when subdivided into local batteries.
  • I claim 1 In a telephone system, a normally-closed main circuit, a normally-open main circuit and a plurality of stations thereon, in combination with a signal at each station on the normallyopen circuit, a telephone-receiver and an induction-coil in a shunt from the normally-open circuit at each station, a circuit containing a telephone-transmitter pass ing through the primary winding of each in- ClllGhlQ11-COl1, a selective mechanism and acircuit-breaker on the normally-closed circuit at each station, and a source of electrical energy, substantially as described.
  • an escapement mechanism operated by an electromagnet for rotating said disk, a normallyclosed circuit passing through the electro magnet, a circuit-breaker in the normallyclosed circuit, a normally-open circuit containin g a signal-bell and adapted to be closed by the rotary movement of the disk, an induction-coil, a telephone-receiver and the secondary winding of the induction-coil in a shunt from the normally-open circuit, a telephone-transmitter and the primary winding of the induction-coil in a local circuit, and a source of electrical energy, substantially as described.
  • A. telephone system having a plurality of stations, a normally-closed circuit and a normally-open circuit passing through said stations, a selective mechanism on the closed ICC 10 with the primary winding of each inductioncoil, a telephone-receiver and the secondary winding of each induction-coil in a shunt from the normallyopen circuit, and a battery, substantially as described.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)

Description

0 0 N 87 2 G u A o 6 t n e t a P H G u R .m F 2% 0 7 6 5 6 0 N TELEPHONE SYSTEM.
(Application filed June 28, 1899.)
2 Sheets-Sheet I.
(No Model.)
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m: mums wz'rzns ca. PHOTO-LIYMO, WASHVNGTON, 01c.
Patented Aug. 28, I900.
2 Sheets-Sheet 2.
F. G. HUGH.
TELEPHONE SYSTEM.
Application filed June 28, 1899.) (No Model.)
H "I Elywemtoz 1 wi Elite 0mm 1': Norms PETERS co, PHOTCLLIYHO wAsnmcToN. 04 c4 rrn "STATES" PATENT OFFICE.
FRANK GLENN RUGI'I, OF BRIAR BLUFF, ILLINOIS, ASSIGNOR OF ONE- FOURTH TO WILSON IV. ADAMS, OF ATKINSON, ILLINOIS.
TELEPHONE. SYISTEM.
SPECIFICATION forming part a Letters Patent No. 656,703, and August 28, 1900.
Application filed June 28, 1899.
To ctZZ whom it may concern: q
Be it known thatI, FRANK GLENN RUGH, a citizen of the United States, residing at Briar Bluff, in the county of Henry and State of Illinois, have invented certain new and useful Improvements in Telephone Systems; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art'to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part ofthis specification.
This invention relates to a telephone system, by the use of which any one station or subscriber on a line containing three or more instruments may be called up without the call being rung at the remainingstations, which latter being cut out of the calling circuit will remain quiet. I
It is well known that on telephone lines in which threeor more instruments are in circuit when one subscriber is called the bells of all the instruments on the circuit ring at the same time, giving general warning that some one is about to talk over the line. Great an noyance is occasioned by this general signaling, as personsat the uncalled stations will often remove their telephonesfrom the hooks and listen to the conversation passing over the line. Besides the annoyance of having their conversation overheard the subscribers fail to get the best service, as the interfering parties ground the line when they remove their receivers from the books, which, shunting in a low resistance, interferes with and prevents conversation between persons separated a considerable distance from each other.
The object of my invention therefore is to overcome this defect and soimprove the service that on lines 'includingthree or more instruments in circuit any subscriber on the line may call any other subscriber without informing others of the fact. This object I accomplish by such combination and adj ustment of the parts and the advantageous con-' nections at the instruments that normally all the telephones except one, usually the last called, are cut out of the line. By this arran gemont when one subscriber wishes to talk Serial No. 722,172. (1% model.)
to another he first brings the desired instrument onto the line through means hereinafter described, at the same time automatically cutting out the one previously on the line. After this thecaller turns his magneto-generator in the usual mannerand rings the bell at the desired station. All other instruments being off the line, their bells cannot ring, so
no one other than the person called is aware that the line is in use. This arrangement also permits several lines to be coupled up, making one long circuit, overwhich conversation can be carried on with facility and senumerals 1, 2, and 3) connected by the line- I wires oand b, the former wire being an opencircuit wire when the instruments are not in use, while the wire Z) is a closed-circuit one, the current passing from battery X by way of said wire through the several stations in turn, then to earth, and back to battery. While I have shown but three instruments on the line, any number up to twenty or thirty may be conveniently placed thereon. Each station is provided with a disk D,mounted on a shaft adapted to be rotated by suit able means in the direction of the arrow and controlled in its rotation by a lever L, drawn in one direction by an electromagnet M and in the opposite direction by a spring N. The main-line Wire 19 is connected at each station to the electromagnet M and also to a normallyclosed circuit-breaker or key K, the latter being used to open and close the circuit when the disks D are to' be rotatedfor calling up a station by closing the circuit through line-wire a at that station. On the face of each disk D is a series of numerals, each numeral representing a station on the line.
Fixed to each disk at its respective stationnumber is a pin 19, adapted to close connection between a pair of spring-fingers S or other circuit-closing device in the main line a. The circuit-closing fingers S are so arranged with relation to the numerals on their approximate disks that when any number say 1 at one station is beneath the circuitclosing fingers the same number on the disks at all the other stations will be in similar position. The pins 19, however, being placed opposite a dii't'erent number ateaoh station, it follows that no two stations can be cut in at the same time. Whenvone of the keys K is operated, the circuit through the main line 1), ground E, and battery X is causing all the leversL to vibrate and the severaldisks to move synchronously in the directionof the arrow.
To one of the fingers S of the circuit-closing fingers S at each station is attached a wire 0, which is connected to the magnet of a sig nal-bell B, and thence passes to and is attached to a contact point or stop 6 beneath the telephone-hook H, which connects therewith when the receiver is hung on said hook. A wire h passes from the hook H to ground. A shunt-wire d at each station is connected to the spring-finger S and passes thence to a magneto-generator G, being attached to a normally-open contact at, which is automatically closed in the well-known manner when the generator is operated. A wire at connects the armature of the generator G to the telephone-hook H. At each station the ordinary telephone-hook H is raised by means of a spring into contact with two contact points or stops fand-g when the telephone or receiver is removed; but when it is hung thereon it (the hook) is drawn down into contact with the stop 6, heretofore described. From the stopfa wire 11 passes to one end of the primary winding of an induction-coilI, and a wire a" connects one endof the secondary winding of the coil to the same stop f. The opposite end of the primary winding of the induction-coil is connected by a wire 25 to a battery 00, transmitting-telephone T, and the stop g. The other end of the secondary winding of the induction-coil is attached to a receivingtelephone R by means of a wire 1', which extends thence to the shunt-wire d, connected, as heretofore described, to the main-line wire (1.
The operation of the system above described is as follows: Suppose the subscriber at station 1 desires to call up station 3. He must first operate his key K, which will open and close the circuit through the main-line wire 6, magnets M, battery X, and earth. This will cause all the disks on the line, be there three or thirty,to move synchronously. When the numeral 3 on the disk of the calling station reaches a position beneath the circuitcloser S, the operator, knowing that the pin 9 on the disk at station 3 has brought the fingers s s of circuit-closer S into contact, removes his finger t'rom the key and turns his generator. The circuit through the generator being automatically closed by this operation,
the current passes from the generator by way ground, returning to station 1, up wire'h to telephone-hook, and by Way of wire d back to generator. The subscriber at station 3 hearing his bell ring removes his receiver R from the hook H and calls station 1, who in the meantime has removed his receiver from its hook H, and they proceed to talk. Each transmitting-telephone is in an independent circuit formed by a battery 00, primary winding of the local induction-coil I, wire 1, stops f g, telephone-hook H, and Wire 25. The receiving-telephone R is in the secondary circuit of. the active induction-coils I, the current of which passes from the coil by wire 1" through the receiver Rvto wire 01 and mainline wire a to station 3, thence by wires dand rof said station 3 througlnreceiver R to the secondary winding of coil I, wire 2', to stopf, telephone-hook H, which had been drawn into contact with stop f and 9 when the receiver R was removed, and wire it to ground, back to station 1 and by way of Wire h, telephonehook I-I, stop f, and wire t" to coil I. The receivers R having been removed from their hooks H, the latter are drawn up by their springs, breaking the circuit through the bell at the stop 6 and closing the circuits through the transmitters T and receivers R by connecting the stops fa'nd g. The circuit-closers S of all other instruments except at station 3 being open and no other bell than that at station 3 being sounded, the other subscribers on the line will not know that the line is being used. Hence they will not take their receivers off the hooks H.
The secondary circuit, which contains the receivers R, is, as hereinbefore described, a ground-circuit; but by omitting the groundwire h and connecting each book H to the main-line wire I), as shown by the dotted lines L, a metallic circuit is formed.
The disk D, on theface of which the various station-numbers are placed and to which the pin 19 is attached, is secured to a shaft D, (see Figs. 3 and 4,) adapted to be rotated by any suitable clock -mechanism. An escapement-wheel D on the shaft D is engaged by pallets D on the arm L, to which an armature D is attached. The lever L, heretofore described, is moved in opposite directions or vibrated by the alternate action of the electromagnet M and spring N. Each movement of the lever L allows the escapement-wheel D to turn the distance of one tooth, which will gradually and intermittently bring the pinp on the disk D into position to close the circuit-closer S.
The modified form of my telephone system illustrated in Fig. 2 differs in some respects from the form shown in Fig. 1. In the system shown in Fig. 2 I use but one battery for all purposes-that is to say, for bringing a station onto the line a, ringing the bell, and
vitalizing the primary circuit of the induction-coils. A circuit-changer O is introduced into the main-line circuit 1) at each station for shunting the current around the magnets M and through the signal-bell B. To each telephone-hook H an insulated plate j is attached to its upper side and a similar plate secured to its under side. Contact points or stops m n are so placed that when the receiver R is removed from the hook H a spring will lift the hook and bring the insulated plate into electrical connection with said contact-points m n. The same movement will close a circuit between the hook H and a contact-point 0. The weight of the receiver when on the hook breaks connection with the contactpoints m, 'n, and 0 and lowers the hook into contact with the stop e. The stops p g are by the same movement electrically connected by the insulated plate 70. The circuits are as follows: To call up station 1 from station 3, the key K at station 3 is operated until the disk D indicates that the pin 19 at station 1 has closed the fingers of circuit-closer S. As in Fig. 1, the main-line circuit b is a closed circuit passing from battery X by wire I) to stop q beneath the hook H, insulated plate 70, stop 19, again on wire I), through the key K and circuit-changer O at station 3 to the main-line wire Z),which enters station 2, and, passing over a similar route therein, as in station 3, continues to station 1, where after again passing through the instrument in a similar manner it goes to ground and back to station 3. After having cut in station 1 the operator at station 3 presses his circuitchanger G into contact with point a shunting the current around the magnet M and by Way of wire a and main-line wire a to finger S of the circuit-closer at station 1 without passing through the instrument at station 2. When the current reaches station 1, it passes through the circuit-closer S to bell B by wire 0, thence to stop e,telephone-hook Hto ground and back to battery, causing bell B at station 1 to ring until the circuit-changer O at station 3 is released. When the finger has been removed from the circuit-changer G and the receivers taken from their hooks H, the said hooks are lifted immediately into contact with the points 122, n, and 0. While the persons at each station are talking, the primary circuit is from the batteryX by wires 1) 25 through transmitter to the primary winding of the induction-coil I at station 3, from whence it passes by wired to stop a, across the insulated platej to stop m, and by Wire 6 to mainline wire I), out of station 3 to stations 2 and l in succession, through which the circuit passes in a similar manner,as in station 3. AE- ter passing through station 1 the circuit is completed through the ground to battery X. By this arrangement the primary circuit passes through the two transmitters in use on theline. The secondary circuit is readily traced from the secondary Winding of the induction-coil at station 3 through the receiver R by way of wire 4" to main-line wire a, running directly to station 1, thence through wire 0 at that station, receiver R, secondary winding of inductioncoil 1, wire e" to stop 0, thence over the hook H, wire it to ground, back to station 3, and by wire it, hook H, stop 0, and wire 71 to induction-coil I, from whence it started. The advantage in this arrangement over that now in use consists in having one battery only to generate all the energy necessary for the entire line, thus doing away with local batteries and magneto-generators and bells at each station, an ordinary electric bell being substituted for the magneto-bell now in use. The battery being at the central station or at one end, it can be cared for and kept in order more readily than when subdivided into local batteries.
Having thus described my invention, I claim 1. In a telephone system, a normally-closed main circuit, a normally-open main circuit and a plurality of stations thereon, in combination with a signal at each station on the normallyopen circuit, a telephone-receiver and an induction-coil in a shunt from the normally-open circuit at each station, a circuit containing a telephone-transmitter pass ing through the primary winding of each in- ClllGhlQ11-COl1, a selective mechanism and acircuit-breaker on the normally-closed circuit at each station, and a source of electrical energy, substantially as described.
2. In combination with a rotatable disk, an escapement mechanism operated by an electromagnet for rotating said disk, a normallyclosed circuit passing through the electro magnet, a circuit-breaker in the normallyclosed circuit, a normally-open circuit containin g a signal-bell and adapted to be closed by the rotary movement of the disk, an induction-coil, a telephone-receiver and the secondary winding of the induction-coil in a shunt from the normally-open circuit, a telephone-transmitter and the primary winding of the induction-coil in a local circuit, and a source of electrical energy, substantially as described.
3. The combination of a normally-closed electric circuit, a series of telephone-stations each containing a selective mechanism on the said circuit, a normally-open electric circuit, a series of circuit-closers on the open circuit adapted to be closed each by one of the selective mechanisms, a shunt circuit from the closed circuit through a telephone-transmitter and the primary winding of an inductioncoil at each station, a shunt-circuit from the closed circuit to the open circuit around each selective mechanism, a signal-bell circuit at each station adapted to form a part of the main open circuit, and a battery for furnishing energy to the several circuits.
4. A. telephone system having a plurality of stations, a normally-closed circuit and a normally-open circuit passing through said stations, a selective mechanism on the closed ICC 10 with the primary winding of each inductioncoil, a telephone-receiver and the secondary winding of each induction-coil in a shunt from the normallyopen circuit, and a battery, substantially as described.
In testimony whereof I affix my signature 15 in presence of two Witnesses.
FRANK GLENN RUGII. Witnesses:
PAUL D. RANSOM, W. W. ADAMS.
US72217299A 1899-06-28 1899-06-28 Telephone system. Expired - Lifetime US656703A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050251673A1 (en) * 2004-05-05 2005-11-10 International Business Machines Corporation Updatable firmware having boot and/or communication redundancy
US20070046791A1 (en) * 2002-10-09 2007-03-01 Xpoint Technologies, Inc. Method and system for deploying a software image

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070046791A1 (en) * 2002-10-09 2007-03-01 Xpoint Technologies, Inc. Method and system for deploying a software image
US20050251673A1 (en) * 2004-05-05 2005-11-10 International Business Machines Corporation Updatable firmware having boot and/or communication redundancy

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