US3274515A - Pulser for modulated anode tubes - Google Patents

Pulser for modulated anode tubes Download PDF

Info

Publication number
US3274515A
US3274515A US248464A US24846462A US3274515A US 3274515 A US3274515 A US 3274515A US 248464 A US248464 A US 248464A US 24846462 A US24846462 A US 24846462A US 3274515 A US3274515 A US 3274515A
Authority
US
United States
Prior art keywords
anode
cathode
modulating
pulser
potential
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US248464A
Inventor
George M W Badger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Varian Medical Systems Inc
Original Assignee
Varian Associates Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Varian Associates Inc filed Critical Varian Associates Inc
Priority to US248464A priority Critical patent/US3274515A/en
Priority to GB50074/63A priority patent/GB1055095A/en
Priority to DE19631464586 priority patent/DE1464586A1/en
Application granted granted Critical
Publication of US3274515A publication Critical patent/US3274515A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K3/00—Circuits for generating electric pulses; Monostable, bistable or multistable circuits
    • H03K3/78—Generating a single train of pulses having a predetermined pattern, e.g. a predetermined number
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/02—Cathode ray tubes; Electron beam tubes having one or more output electrodes which may be impacted selectively by the ray or beam, and onto, from, or over which the ray or beam may be deflected or de-focused

Definitions

  • This invention relates to pulsers for modulated anode tubes.
  • an electron gun 11 including a filament 13, a cathode 15, and a focusing electrode 17.
  • the cathode 15 and the focusing electrode 17 are connected to a cathode terminal 19.
  • a modulating anode 21 and an accelerating anode 23 are shown.
  • the beam emerging from the accelerating anode 23 passes into the radio frequency section of the tube indicated by the dotted line 24. This section may be of the klystron type or others.
  • a source of potential 25 is connected between the cathode terminal 19 and the accelerating anode 23.
  • a diode 27 and transformer 29 are connected in series between the cathode terminal 19 and the modulating anode 21.
  • a second diode 31 and a second transformer 33 are connected in series between the modulating anode 21 and the accelerating anode 23.
  • a resistor 35 may be connected across the series combination including the diode 27 and the transformer 29 to provide a leakage path so that when the tube is initially turned on, the modulating anode is essentially at the same voltage as the cathode. In this condition, the beam is cut off.
  • Interelectrode capacitances 37 and 39 of the gun are designated by dashed lines.
  • the capacitor 37 represents the interelectrode capcitance between the cathode structure including terminal 19 and the modulating anode 21, while the capacitor 39 represents the interelectrode capacitance between the modulating anode 21 and the accelerating anode 23.
  • additional capacitance may be added externally if necessary for operation.
  • each of the transformers 29 and 33 it should be noted that it is the secondary winding which is connected in series with the respective diode 27 and 31.
  • the primaries of the individual transformers are connected to a pulse source which may be employed to turn the gun on and off in accordance with the invention.
  • the modulating anode 21 which controls the flow of current to turn the tube on and off.
  • the accelerating anode merely provides the acceleration to the electrons forming the beam.
  • the modulating anode 21 is at the potential of the cathode, the gun will be turned off.
  • the modulating anode 21 is held at the Patented Sept. 20, 1966 potential of the accelerating anode 23 or at any potential positive with respect to the cathode, the gun will be turned on.
  • the modulating anode 21 In the quiescent state, the modulating anode 21 will be held at or near the potential of the cathode due to its connection through the resistor 35 to the cathode terminal 19. Consequently, in a quiescent state, the gun will be in its ofl condition.
  • a positive pulse is applied to the primary of the pulse transformer 29.
  • the turns ratio of the transformer and the amplitude of the input pulse are selected so that the voltage appearing across the secondary of the transformer 29 is a positive pulse of suflicient amplitude to cause the diode 27 to conduct.
  • This brings the cathode of the diode 27 to the potential of the anode of the diode 27 which is the peak pulse voltage.
  • This drives the modulating anode 21 to the pulse potential which, in the fully turned on condition of the gun, is the potential of the accelerating anode 23.
  • the diode 27 conducts during the pulse interval and during this momentary conduction, it permits the interelectrode capacitance 39 to discharge.
  • the modulating anode 21 will remain at the relatively high pulsevoltage.
  • the gun continues to inject an electron beam even though both of the diodes 27 and 31 are nonconducting.
  • a pulse is applied to the primary of the pulse transformer 33.
  • the pulse amplitude is such that it will cause the diode 31 to conduct whereby the plate and cathode of the diode 31 are at substantially the same potential.
  • the magnitude of the input pulse and turns ratio of the pulse transformer are selected to drive the diode into conduction.
  • the interelectrode capacitance 37 is discharged through the diode 31.
  • the modulating anode 21 Upon termination of the pulse, the modulating anode 21 will be at substantially cathode potential and remain there until the next turn-on pulse.
  • a pulser for a modulating anode tube of the type including a cathode, an anode and a modulating means comprising means for applying a source of accelerating voltage between the cathode and anode, a first series combination including a switching transformer and a diode connected between the cathode and modulating means, a second series combination including a second switching transformer and diode connected between the modulating means and a source of potential positive with respect to the cathode, and means for selectively applying switching pulses to said transformers whereby the modulating anode tube may be selectively turned on or off.
  • a pulser for a modulating anode tube of the type which include a cathode, a modulating anode and an accelerating anode comprising means for applying a source of potential between the cathode and the accelerating anode, a first series combination including uni-directional conducting means presenting relatively high impedance for current flow in one direction and a selective low impedance in the opposite direction connected between the cathode and modulating anode, means for selectively causing said first series combination including uni-directional conducting means to connect said modulating anode to the cathode, a second series combination including a uni-directional conducting means adapted to provide a high impedace to current flow in one direction and a relatively low impedance in the other direction connected between the modulating anode and a source of potential positive with respect to the cathode, and means for selectively applying switching voltages to said second series combination including unidirectional conducting means to connect the modulating anode to a source of positive potential.
  • a pulser for modulated tubes of the type which include a cathode, a modulating electrode and an accelerating anode comprising means for applying a source of potential between the cathode and the accelerating anode, a first series combination including uni-directional conducting means presenting relatively high impedance for current flow in one direction and a selective low impedance in the opposite direction connected between the cathode and modulating electrode, a second series combination including a uni-directional conducting means adapted to provide a high impedance to current fiow in one direction and a relatively low impedance in the opposite direction connected between the modulating electrode and accelerating electrode, and means for selectively applying switching voltages to said uni-directional conducting means whereby the modulating electrode is selectively connected to the cathode and anode to turn the tube on and off.
  • a pulser as in claim 5 wherein said means for selectively applying switching voltages comprises a pulse transformer connected in series with each of said uni-directional conducting means.

Description

p 20, 1966 G. M. w. BADGER 3,274,515
PULSER FOR MODULATED ANODE TUBES Filed Dec. 51, 1962 GEORGE M. W. BADGER INVENTOR.
BY wwwz ATTORNEY United States Patent 3,274,515 PULSER FOR MODULATED ANQDE TUBES George M. W. Badger, Menlo Park, Calili, assignor, by mesne assignments, to Varian Associates, a corporation of California Filed Dec. 31, 1962, Ser. No. 248,464 7 Claims. (Cl. 332-7) This invention relates to pulsers for modulated anode tubes.
In pulsed operation of electron beam tubes of the type which include a modulating anode, there are required means for rapidly changing the potential of the modulating anode. This is ordinarily accomplished by a switch tube, such as a triode.
It is an object of this invention to provide improved means for pulsing modulated anode beam tubes.
It is a more particular object of this invention to provide an improved means for pulsing a modulated anode beam tube wherein switch tubes are not required.
It is still another object of this invention to provide a circuit for pulsing a modulated anode beam tube employing diodes and pulse transformers rather than the usual switch tubes.
These and other objects and features of the invention will become more clearly apparent upon a review of the following description in conjunction with the accompanying drawing which is a schematic diagram of a pulser for a modulating anode tube in accordance with this invention.
Referring to the figure, there is shown an electron gun 11 including a filament 13, a cathode 15, and a focusing electrode 17. The cathode 15 and the focusing electrode 17 are connected to a cathode terminal 19. In addition, there is shown a modulating anode 21 and an accelerating anode 23. The beam emerging from the accelerating anode 23 passes into the radio frequency section of the tube indicated by the dotted line 24. This section may be of the klystron type or others.
A source of potential 25 is connected between the cathode terminal 19 and the accelerating anode 23. A diode 27 and transformer 29 are connected in series between the cathode terminal 19 and the modulating anode 21. A second diode 31 and a second transformer 33 are connected in series between the modulating anode 21 and the accelerating anode 23. A resistor 35 may be connected across the series combination including the diode 27 and the transformer 29 to provide a leakage path so that when the tube is initially turned on, the modulating anode is essentially at the same voltage as the cathode. In this condition, the beam is cut off.
Interelectrode capacitances 37 and 39 of the gun are designated by dashed lines. Thus, the capacitor 37 represents the interelectrode capcitance between the cathode structure including terminal 19 and the modulating anode 21, while the capacitor 39 represents the interelectrode capacitance between the modulating anode 21 and the accelerating anode 23. It will be apparent from the description below that additional capacitance may be added externally if necessary for operation. In the case of each of the transformers 29 and 33, it should be noted that it is the secondary winding which is connected in series with the respective diode 27 and 31. The primaries of the individual transformers are connected to a pulse source which may be employed to turn the gun on and off in accordance with the invention.
It should be realized that it is the potential of the modulating anode 21 which controls the flow of current to turn the tube on and off. The accelerating anode merely provides the acceleration to the electrons forming the beam. Thus, if the modulating anode 21 is at the potential of the cathode, the gun will be turned off. On the other hand, if the modulating anode 21 is held at the Patented Sept. 20, 1966 potential of the accelerating anode 23 or at any potential positive with respect to the cathode, the gun will be turned on.
In the quiescent state, the modulating anode 21 will be held at or near the potential of the cathode due to its connection through the resistor 35 to the cathode terminal 19. Consequently, in a quiescent state, the gun will be in its ofl condition.
In order to turn the gun on, a positive pulse is applied to the primary of the pulse transformer 29. The turns ratio of the transformer and the amplitude of the input pulse are selected so that the voltage appearing across the secondary of the transformer 29 is a positive pulse of suflicient amplitude to cause the diode 27 to conduct. This brings the cathode of the diode 27 to the potential of the anode of the diode 27 which is the peak pulse voltage. This drives the modulating anode 21 to the pulse potential which, in the fully turned on condition of the gun, is the potential of the accelerating anode 23. The diode 27 conducts during the pulse interval and during this momentary conduction, it permits the interelectrode capacitance 39 to discharge. At the termination of the pulse, the modulating anode 21 will remain at the relatively high pulsevoltage. The gun continues to inject an electron beam even though both of the diodes 27 and 31 are nonconducting.
In order to turn the gun oif, a pulse is applied to the primary of the pulse transformer 33. The pulse amplitude is such that it will cause the diode 31 to conduct whereby the plate and cathode of the diode 31 are at substantially the same potential. Again, the magnitude of the input pulse and turns ratio of the pulse transformer are selected to drive the diode into conduction. The interelectrode capacitance 37 is discharged through the diode 31. Upon termination of the pulse, the modulating anode 21 will be at substantially cathode potential and remain there until the next turn-on pulse.
Although there is shown and described conventional electronic type diodes, it is apparent that semiconductive diodes and other controlled rectifying means may be employed to carry out the function described above.
Thus, it is seen that switching of the tube from the off to the on condition and back is essentially performed by diodes in association with the pulse transformers. The amount of energy which is required to give the pulsed operation is minimal and, therefore, the efliciency of the system is relatively good.
I claim:
1. A pulser for a modulating anode tube of the type including a cathode, an anode and a modulating means comprising means for applying a source of accelerating voltage between the cathode and anode, a first series combination including a switching transformer and a diode connected between the cathode and modulating means, a second series combination including a second switching transformer and diode connected between the modulating means and a source of potential positive with respect to the cathode, and means for selectively applying switching pulses to said transformers whereby the modulating anode tube may be selectively turned on or off.
2. A circuit as defined in claim 1 together with resistive means connected between said cathode and modulating means.
3. A pulser for a modulating anode tube of the type which include a cathode, a modulating anode and an accelerating anode comprising means for applying a source of potential between the cathode and the accelerating anode, a first series combination including uni-directional conducting means presenting relatively high impedance for current flow in one direction and a selective low impedance in the opposite direction connected between the cathode and modulating anode, means for selectively causing said first series combination including uni-directional conducting means to connect said modulating anode to the cathode, a second series combination including a uni-directional conducting means adapted to provide a high impedace to current flow in one direction and a relatively low impedance in the other direction connected between the modulating anode and a source of potential positive with respect to the cathode, and means for selectively applying switching voltages to said second series combination including unidirectional conducting means to connect the modulating anode to a source of positive potential.
4. A pulser as in claim 3 wherein said source of positive potential is the accelerating anode.
5. A pulser for modulated tubes of the type which include a cathode, a modulating electrode and an accelerating anode comprising means for applying a source of potential between the cathode and the accelerating anode, a first series combination including uni-directional conducting means presenting relatively high impedance for current flow in one direction and a selective low impedance in the opposite direction connected between the cathode and modulating electrode, a second series combination including a uni-directional conducting means adapted to provide a high impedance to current fiow in one direction and a relatively low impedance in the opposite direction connected between the modulating electrode and accelerating electrode, and means for selectively applying switching voltages to said uni-directional conducting means whereby the modulating electrode is selectively connected to the cathode and anode to turn the tube on and off.
6. A pulser as in claim 5 wherein said means for selectively applying switching voltages comprises a pulse transformer connected in series with each of said uni-directional conducting means.
7. A pulser as in claim 5 wherein said uni-directional conducting means comprises diodes.
References Cited by the Examiner UNITED STATES PATENTS 2,881,349 4/1959 Eichenbaum et al. a 332-7 X ROY LAKE, Primary Examiner.
A. L. BRODY, Assistant Examiner.

Claims (1)

1. A PULSER FOR MODULATING ANODE TUBE OF THE TYPE INCLUDING A CATHODE, AN ANODE AND A MODULATING MEANS COMPRISING MEANS FOR APPLYING A SOURCE OF ACCELERATING VOLTAGE BETWEEN THE CATHODE AND ANODE, A FIRST SERIES COMBINATION INCLUDING A SWITCHING TRANSFORMER AND A DIODE CONNECTED BETWEEN THE CATHODE AND MODULATING MEANS, A SECOND SERIES COMBINATION INCLUDING A SECOND SWITCHING TRANSFORMER AND DIODE CONNECTED BETWEEN THE MODULATING MEANS AND A SOURCE OF POTENTIAL POSITIVE WITH RESPECT TO THE CATHODE, AND MEANS FOR SELECTIVELY APPLYING SWITCHING PULSES TO SAID TRANSFORMERS WHEREBY THE MODULATING ANODE TUBE MAY BE SELECTIVELY TURNED "ON" OR "OFF."
US248464A 1962-12-31 1962-12-31 Pulser for modulated anode tubes Expired - Lifetime US3274515A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US248464A US3274515A (en) 1962-12-31 1962-12-31 Pulser for modulated anode tubes
GB50074/63A GB1055095A (en) 1962-12-31 1963-12-18 Pulser for modulated beam tubes
DE19631464586 DE1464586A1 (en) 1962-12-31 1963-12-30 Pulse generator for modulated anode tubes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US248464A US3274515A (en) 1962-12-31 1962-12-31 Pulser for modulated anode tubes

Publications (1)

Publication Number Publication Date
US3274515A true US3274515A (en) 1966-09-20

Family

ID=22939248

Family Applications (1)

Application Number Title Priority Date Filing Date
US248464A Expired - Lifetime US3274515A (en) 1962-12-31 1962-12-31 Pulser for modulated anode tubes

Country Status (3)

Country Link
US (1) US3274515A (en)
DE (1) DE1464586A1 (en)
GB (1) GB1055095A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3772613A (en) * 1972-09-11 1973-11-13 Rca Corp Balanced line type pulser circuit
US3784799A (en) * 1972-05-08 1974-01-08 Northrop Corp High speed deflection modulator electron beam signal processor
US3806836A (en) * 1972-01-10 1974-04-23 R Alsmeyer Simplified floating deck pulse modulator

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2881349A (en) * 1957-05-23 1959-04-07 Rca Corp Control device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2881349A (en) * 1957-05-23 1959-04-07 Rca Corp Control device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3806836A (en) * 1972-01-10 1974-04-23 R Alsmeyer Simplified floating deck pulse modulator
US3784799A (en) * 1972-05-08 1974-01-08 Northrop Corp High speed deflection modulator electron beam signal processor
US3772613A (en) * 1972-09-11 1973-11-13 Rca Corp Balanced line type pulser circuit

Also Published As

Publication number Publication date
GB1055095A (en) 1967-01-11
DE1464586A1 (en) 1969-02-06

Similar Documents

Publication Publication Date Title
US2532738A (en) Arrangement comprising a cathoderay tube having means for deflecting the cathode-ray beam
US2258752A (en) Saw-tooth wave generator circuit arrangement
US3636476A (en) Solid-state double resonant pulser
US3274515A (en) Pulser for modulated anode tubes
US2429471A (en) Pulse generating circuit
US3697880A (en) Circuit for switching between two unidirectional voltages
US2896124A (en) Gaseous glow tube circuits
US2537862A (en) High-voltage pulse generator
US2456754A (en) Electronic saw-tooth pulse generator
US2653236A (en) Frequency dividing circuit
US3349279A (en) Electronic circuit
US2191903A (en) Electron discharge device
US3806836A (en) Simplified floating deck pulse modulator
US2495183A (en) Arc welding apparatus
US2496980A (en) Pulsed oscillator
US2922037A (en) Quick recovery circuit for blocking oscillators
US2402364A (en) Velocity modulation impulse generator
US2612620A (en) Bridge type deflection circuit
US2364761A (en) Electron discharge device
US2577164A (en) Electronic device
US2413181A (en) Signal generator
US2631233A (en) Secondary emission trigger circuit
US2719229A (en) Bistable switching circuit
US3295066A (en) Multiple modulating anode beam type electron tube and modulating circuit
US3105169A (en) Pulse generator