US2497640A - Secondary emission amplifying tube circuit - Google Patents

Secondary emission amplifying tube circuit Download PDF

Info

Publication number
US2497640A
US2497640A US685202A US68520246A US2497640A US 2497640 A US2497640 A US 2497640A US 685202 A US685202 A US 685202A US 68520246 A US68520246 A US 68520246A US 2497640 A US2497640 A US 2497640A
Authority
US
United States
Prior art keywords
grid
anode
electrode
circuit
capacity
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
US685202A
Inventor
Adelbert Van Weel
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.)
Hartford National Bank and Trust Co
Original Assignee
Hartford National Bank and Trust Co
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 Hartford National Bank and Trust Co filed Critical Hartford National Bank and Trust Co
Application granted granted Critical
Publication of US2497640A publication Critical patent/US2497640A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/02—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements with tubes only
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J19/00—Details of vacuum tubes of the types covered by group H01J21/00
    • H01J19/28—Non-electron-emitting electrodes; Screens
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/02—Tubes in which one or a few electrodes are secondary-electron emitting electrodes
    • H01J43/025—Circuits therefor
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/08—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/42—Modifications of amplifiers to extend the bandwidth
    • H03F1/48—Modifications of amplifiers to extend the bandwidth of aperiodic amplifiers
    • H03F1/50—Modifications of amplifiers to extend the bandwidth of aperiodic amplifiers with tubes only
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0001—Electrodes and electrode systems suitable for discharge tubes or lamps
    • H01J2893/0012—Constructional arrangements

Definitions

  • Thisinvention relates to a circuit-arrangement for the transmission of electric oscillations, particularly of a wide frequency band or of ultrahigh frequencies, in which a discharge tube is used which is provided with a secondary emission electrode which also acts as an output electrode and which in the proximity of the secondary emission electrode andin the path of the secondary electrons comprises a grid whose bias is higher than that of the secondary emission electrode.
  • the amplification to be obtained is generally limited, so that for this purpose use may be made with advantage of the so-called secondary emission tubes, which have a very high mutual conductance. It may, in some cases, be of use to employ the secondary emis-- sion electrode also as an output electrode. This measure may be taken, for example, if an amplification without phase shift is desired or if two frequency bands (for example, image and sound frequencies in television) are to be separated; in the latter case the oscillations associated with one of the bands may be taken from the anode and the oscillations associated with the other band from the secondary-emission electrode.
  • a grid is frequently arranged in secondary emission tubes in the proximity of the secondaryemission electrode and in the path of the secondary electrons, said grid having a higher bias than the secondary-emission electrode, for example the same bias as the anode, and having the function of drawing away thesecondary electrons from the secondary-emission electrode.
  • This grid is generally connected direct to the anode inside the tube; its has, however, also been suggested before to provide the grid concerned with a separate supply lead.
  • the capacity between the secondary emission electrode and the cathode is comparatively high, so that the secondary emission electrode cannot be utilized without difficulty as an output electrode.
  • the invention has for its object to obviate t'his disadvantage
  • a high impedance for the oscillations to be transmitted is provided between the said? grid and the source of direct voltage which supplies the bias for this grid.
  • the said grid is preferably connected to the source of direct voltage through a high-ohmic resistance.
  • the said resistance may be arranged, for example, inside the tube between the said grid and the anode.
  • an amplifier for a wide frequency band comprising a discharge tube 1 which is provided with a cathode 2, a control grid 3, a screen grid 4, a secondary emission electrode 5, a grid 6 arranged in the path of the secondary electrons and an anode I.
  • the oscillations to be amplified are supplied to the control grid 3 through terminals 8 and 9.
  • the circuit of the secondary emission electrode includes a resistance I 0, from which the amplified oscillations are obtained through terminals H and I2.
  • the anode I is connected to earth, via a condenser l3, for the frequencies of the oscillations to be amplified.
  • a resistance l4 shunted by a condenser is included in the cathode lead in the usual manner for the generation of the control grid bias.
  • the grid 5 is connected to the anode 1 through a high-ohmic resistance l5.
  • the effect of this measure may be explained as follows.
  • the grid 6 was connected direct to the anode l, the capacity between the secondary-emission electrode and earth being primarily constituted by the capacity C1 between the secondary-emission electrode and the anode and by the capacity C2 between the secondary-emission electrode and the grid 6 and being consequently Ci-l-Cz; the other capacities between the secondary-emission electrode and earth (for example, the parasitic capacity of the resistance l and the capacity between the secondary-emission electrode and the screen grid 4) may be assumed to be included in the capacity C1.
  • the grid 6 is practically insulated with respect to earth by the high impedance included in the circuit of this grid, so that for the capacity between the secondary emission electrode and the grid 6 is substituted the series combination of this capacity and the capacity 03 between the grid 6 and the anode 1.
  • the total capacity between the secondary-emission electrode and earth is and is consequently lower than in the usual circuit-arrangements.
  • a considerable reduction (for example of several pis.) of the total output capacitive reactions is obtainable in practice by the use of the invention.
  • the resistance I is preferably arranged inside the tube between the grid 6 and the anode.
  • the resistance l5 may, in practice, have a value of several megohms.
  • the invention may also be used with advantage in circuit-arrangements in which the tube l is provided with a photo-electric cathode instead of the cathode 2 and the control grid 3.
  • An electric wave transmission circuit comprising a thermionic discharge tube having a cathode, anode, secondary emissive electrode and a grid included in the electron path between said anode and secondary electrode, a source of desired signals, means to modulate the electron path of the said thermionic discharge tube in accordance with said signals, a first source of direct current potential of given voltage, an output stage, means to couple said first source of potential and said output stage to the secondary emissive electrode-cathode circuit of said thermionic discharge tube, a resistive element, means to connect said resistive element between said grid and the anode of the said thermionic discharge tube, a second source of direct current potential having a higher voltage than the first source of potential, and means to connect said second source of potential to the anode of said thermionic discharge tube.
  • An electric wave transmission circuit comprising a thermionic discharge tube having a cathode, anode, secondary emissive electrode and a grid included in the electron path between said anode and secondary electrode, a resistive element connected internally in said thermionic discharge tube between the anode and the grid, a first source of direct current potential of given voltage, an output stage, means to couple said first source of potential and said output stage to the secondary emissive electrode-cathode circuit of said thermionic discharge tube, a second source of direct current potential having a higher voltage than the first source of potential, and means to connect said second source of potential to the anode of said thermionic discharge tube.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Amplifiers (AREA)

Description

Feb. 14, 1950 v w 2,497,640
SECONDARY EMISSION AMPLIFYING TUBE cmppn Filed July 20, 1946 VJNVENTOFK ADELBEPC VAN WEEL BYZ4% %7 AGENT Patented Feb. 14, 1950 SECONDARY EMISSION AMPLIFYING TUBE CIRCUIT Adelbert van Weel, Eindhoven, Netherlands, as-
signor to Hartford National Bank and Trust Company, Hartford, Conn, as trustee Application July 20, 1946, Serial No. 685,202 In the Netherlands August 23, 1943 Section 1, Public Law 690, August 8, 1946 Patent expires August 23, 1963 2 Claims.
Thisinvention relates to a circuit-arrangement for the transmission of electric oscillations, particularly of a wide frequency band or of ultrahigh frequencies, in which a discharge tube is used which is provided with a secondary emission electrode which also acts as an output electrode and which in the proximity of the secondary emission electrode andin the path of the secondary electrons comprises a grid whose bias is higher than that of the secondary emission electrode.
It is known that in the so-called wide band amplifiers the width of the frequency band to be transmitted is solely determined by the capacity occurring between the output electrode and the cathode; the lower the said capacity, the larger is the frequencyband allowed to pass. This remark applies both to circuit-arrangements for the transmission of modulated oscillations (for example high or intermediate frequency amplifiers for television or for frequency-modulated oscillations) and to circuit-arrangements for the transmission of non-modulated oscillations (for example video frequency amplifiers for television). In addition, in amplifiers for ultra-high frequency oscillations the maximum impedance of the output resonant circuit and consequently the achievable amplification are also solely determined by the capacity between output electrode and cathode. It is therefore of paramount importance to take care that this capacity is minimized in circuit-arrangements of the said descriptions.
In the transmission of wide frequency bands and of ultra-high frequencies the amplification to be obtained is generally limited, so that for this purpose use may be made with advantage of the so-called secondary emission tubes, which have a very high mutual conductance. It may, in some cases, be of use to employ the secondary emis-- sion electrode also as an output electrode. This measure may be taken, for example, if an amplification without phase shift is desired or if two frequency bands (for example, image and sound frequencies in television) are to be separated; in the latter case the oscillations associated with one of the bands may be taken from the anode and the oscillations associated with the other band from the secondary-emission electrode.
Now, a grid is frequently arranged in secondary emission tubes in the proximity of the secondaryemission electrode and in the path of the secondary electrons, said grid having a higher bias than the secondary-emission electrode, for example the same bias as the anode, and having the function of drawing away thesecondary electrons from the secondary-emission electrode. This grid is generally connected direct to the anode inside the tube; its has, however, also been suggested before to provide the grid concerned with a separate supply lead. In the use of such tubes in circuit-arrangements for thetransmission of a wide frequency band or of ultra-high frequencies, there is the disadvantage that the capacity between the secondary emission electrode and the cathode is comparatively high, so that the secondary emission electrode cannot be utilized without difficulty as an output electrode.
The invention has for its object to obviate t'his disadvantage According to the invention, to-this end a high impedance for the oscillations to be transmitted is provided between the said? grid and the source of direct voltage which supplies the bias for this grid.
The said grid is preferably connected to the source of direct voltage through a high-ohmic resistance. For this purpose the said resistance may be arranged, for example, inside the tube between the said grid and the anode.
In order that the invention may be clearly understood and readily carried into effect, it will now be explained more fully with reference to the accompanying drawing, in which one form of construction is illustrated.
On the drawing is shown an amplifier for a wide frequency band comprising a discharge tube 1 which is provided with a cathode 2, a control grid 3, a screen grid 4, a secondary emission electrode 5, a grid 6 arranged in the path of the secondary electrons and an anode I. The oscillations to be amplified are supplied to the control grid 3 through terminals 8 and 9. The circuit of the secondary emission electrode includes a resistance I 0, from which the amplified oscillations are obtained through terminals H and I2. The anode I is connected to earth, via a condenser l3, for the frequencies of the oscillations to be amplified. A resistance l4 shunted by a condenser is included in the cathode lead in the usual manner for the generation of the control grid bias.
According to the invention, the grid 5 is connected to the anode 1 through a high-ohmic resistance l5. The effect of this measure may be explained as follows.
In the usual circuit-arrangements the grid 6 was connected direct to the anode l, the capacity between the secondary-emission electrode and earth being primarily constituted by the capacity C1 between the secondary-emission electrode and the anode and by the capacity C2 between the secondary-emission electrode and the grid 6 and being consequently Ci-l-Cz; the other capacities between the secondary-emission electrode and earth (for example, the parasitic capacity of the resistance l and the capacity between the secondary-emission electrode and the screen grid 4) may be assumed to be included in the capacity C1.
In the circuit-arrangement according to the invention the grid 6 is practically insulated with respect to earth by the high impedance included in the circuit of this grid, so that for the capacity between the secondary emission electrode and the grid 6 is substituted the series combination of this capacity and the capacity 03 between the grid 6 and the anode 1. Thus, the total capacity between the secondary-emission electrode and earth is and is consequently lower than in the usual circuit-arrangements. A considerable reduction (for example of several pis.) of the total output capacitive reactions is obtainable in practice by the use of the invention.
In order to avoid an increase of the output capacity by the capacity of the supply lead of the grid 6 with respect to the anode and the secondary-emission electrode the resistance I is preferably arranged inside the tube between the grid 6 and the anode. The resistance l5 may, in practice, have a value of several megohms. The invention may also be used with advantage in circuit-arrangements in which the tube l is provided with a photo-electric cathode instead of the cathode 2 and the control grid 3.
What I claim is:
1. An electric wave transmission circuit comprising a thermionic discharge tube having a cathode, anode, secondary emissive electrode and a grid included in the electron path between said anode and secondary electrode, a source of desired signals, means to modulate the electron path of the said thermionic discharge tube in accordance with said signals, a first source of direct current potential of given voltage, an output stage, means to couple said first source of potential and said output stage to the secondary emissive electrode-cathode circuit of said thermionic discharge tube, a resistive element, means to connect said resistive element between said grid and the anode of the said thermionic discharge tube, a second source of direct current potential having a higher voltage than the first source of potential, and means to connect said second source of potential to the anode of said thermionic discharge tube.
2. An electric wave transmission circuit comprising a thermionic discharge tube having a cathode, anode, secondary emissive electrode and a grid included in the electron path between said anode and secondary electrode, a resistive element connected internally in said thermionic discharge tube between the anode and the grid, a first source of direct current potential of given voltage, an output stage, means to couple said first source of potential and said output stage to the secondary emissive electrode-cathode circuit of said thermionic discharge tube, a second source of direct current potential having a higher voltage than the first source of potential, and means to connect said second source of potential to the anode of said thermionic discharge tube.
ADELBERT VAN WEEL.
REFERENCES CITED The following'references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,201,587 Krawinkel May 21, 1940 2,276,417 Preisach Mar. 17, 1942 2,298,960 McRae Oct. 13, 1942
US685202A 1943-08-04 1946-07-20 Secondary emission amplifying tube circuit Expired - Lifetime US2497640A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL250227X 1943-08-04
NL230843X 1943-08-23

Publications (1)

Publication Number Publication Date
US2497640A true US2497640A (en) 1950-02-14

Family

ID=26643534

Family Applications (1)

Application Number Title Priority Date Filing Date
US685202A Expired - Lifetime US2497640A (en) 1943-08-04 1946-07-20 Secondary emission amplifying tube circuit

Country Status (4)

Country Link
US (1) US2497640A (en)
BE (1) BE457111A (en)
CH (1) CH250227A (en)
FR (1) FR906839A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2798903A (en) * 1951-03-16 1957-07-09 Henry M Spencer Signal amplification system
US3048788A (en) * 1958-08-15 1962-08-07 Edgerton Germeshausen And Grie Sweep signal generating system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2201587A (en) * 1936-04-25 1940-05-21 Krawinkel Gunther Electron discharge device system
US2276417A (en) * 1937-09-30 1942-03-17 Ver Gluhlampen Und Elek Citats Electric amplifier circuits
US2298960A (en) * 1940-08-15 1942-10-13 Bell Telephone Labor Inc Amplification with high efficiency

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2201587A (en) * 1936-04-25 1940-05-21 Krawinkel Gunther Electron discharge device system
US2276417A (en) * 1937-09-30 1942-03-17 Ver Gluhlampen Und Elek Citats Electric amplifier circuits
US2298960A (en) * 1940-08-15 1942-10-13 Bell Telephone Labor Inc Amplification with high efficiency

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2798903A (en) * 1951-03-16 1957-07-09 Henry M Spencer Signal amplification system
US3048788A (en) * 1958-08-15 1962-08-07 Edgerton Germeshausen And Grie Sweep signal generating system

Also Published As

Publication number Publication date
CH250227A (en) 1947-08-15
FR906839A (en) 1946-02-21
BE457111A (en)

Similar Documents

Publication Publication Date Title
US2235414A (en) Thermionic valve circuits
US2547235A (en) High-frequency amplifier, including a velocity modulation tube
US2240715A (en) Amplifier
US2058512A (en) Radio receiver
US2497640A (en) Secondary emission amplifying tube circuit
US3473125A (en) Klystron am transmitters
US2346545A (en) Electron discharge device circuit
US2503780A (en) Mixer circuit
US2342492A (en) Ultra-high-frequency amplifier
US2378797A (en) Electronic tube circuits
US2489266A (en) Cathode-coupled amplifier
US2145368A (en) Amplifier tube and circuit
US2597629A (en) Electron discharge amplifier
US2400734A (en) Direct coupled amplifier
US2026944A (en) Means for receiving and amplifying electric signals
US2097896A (en) Amplifying arrangement
US2174234A (en) Broad band amplifier
US2370221A (en) Electric wave circuits
US2496361A (en) Cathode-ray deflection type amplifier
US2527737A (en) Variable frequency band width amplifier
US2202361A (en) Amplifier circuit
US2473754A (en) Amplifier circuits with double control
US2570016A (en) Superheterodyne receiving circuit arrangement
US1955094A (en) Ultrahigh frequency amplifier
US3116461A (en) Linear amplifier for modulated high frequency oscillations