[go: up one dir, main page]

US2471401A - Neutrodyning for short waves - Google Patents

Neutrodyning for short waves Download PDF

Info

Publication number
US2471401A
US2471401A US735908A US73590847A US2471401A US 2471401 A US2471401 A US 2471401A US 735908 A US735908 A US 735908A US 73590847 A US73590847 A US 73590847A US 2471401 A US2471401 A US 2471401A
Authority
US
United States
Prior art keywords
circuit
primary
spark gap
lead
capacitor
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
US735908A
Other languages
English (en)
Inventor
Ahier Georges
Touraton Emile
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.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
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 International Standard Electric Corp filed Critical International Standard Electric Corp
Application granted granted Critical
Publication of US2471401A publication Critical patent/US2471401A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • H03F1/14—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements by use of neutralising means
    • H03F1/16—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements by use of neutralising means in discharge-tube amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B11/00—Generation of oscillations using a shock-excited tuned circuit
    • H03B11/02—Generation of oscillations using a shock-excited tuned circuit excited by spark

Definitions

  • This invention relates to a spark gap type short wave generator, and more particularly to a radio transmitter utilizing a series resonant circuit in the primary coupled to a parallel resonant circuit in the secondary to substantially prevent a secondary reaction on the spark gap after the initial primary discharge across the spark gap has been dissipated.
  • An important object of the invention is to prevent, in a spark transmitter, the reaction of the secondary oscillatory circuit on the primary oscillatory circuit containing the spark gap and obtain a neutrodyne action.
  • Another object of the invention is a provision for installing coupling capacitors in such a way as to obtain an electrostatic coupling that is reversed with respect to the electromagnetic coupling of the inductors in the resonant circuits at wavelengths shorter than about ten meters.
  • Another object is to provide a radio transmitter circuit employing a primary series resonant cir cuit coupled to a secondary parallel resonant circuit to restrict or substantially prevent secondary reaction on the spark gap to obtain an output having a substantially linear wave shape at wavelengths shorter than about ten meters.
  • a further object of the invention is to provide a spark gap generator of the class set forth, which is of an extremely simplified but durable and eflicient construction and arrangement of parts, and which will be comparatively inexpensive to manufacture.
  • Fig. 1 is a schematic diagram of the circuit of a conventional spark transmitter, for comparison with the circuit of the present invention.
  • Fig. 2 illustrates schematically the configuration of the oscillations received at the terminals 2 of the primary and secondary circuits when spark re-ignition occurs in a circuit as shown in Fig. 1.
  • Fig. 3 illustrates schematically the configuration of the oscillations received at the terminals of the primary and secondary circuits without spark reignition as employed in the invention as shown in the circuit of Fig. 4.
  • Fig. 4 is a schematic diagram of a neutrodyne circuit of a spark transmitter embodying the invention.
  • Fig. 1 two terminals i0 and H, the terminal II is connected to the ground by a lead [2 and the terminal I0 is connected to a resistor 13 by a lead 14.
  • the other end of the resistor i3 is connected to one side of a spark gap I5 by a lead 16 and to a plate of a capacitor 11 by a lead l8.
  • One side of a primary coil 19 of a transformer 20 is connected to the spark gap 15 by a lead 2
  • The'other side of the primary coil I 9 is connected to a plate of a capacitor l'l' by a lead 22 and this lead is connected to the ground.
  • One side of a secondary coil 23 of the transformer 20 is connected to one plate of a capacitor 24 by a lead 25 and the other side of the secondary coil 23 is connected to the other plate of capacitor 24 by a lead 26 and this lead is connected to the ground.
  • One side of an antenna coupling coil 21 is connected to the ground by a lead 30.
  • a voltage source 31 connected to a resistor 32 by a lead 33 and also connected to a second resistor 34 by a lead 35.
  • the resistor 32 is then connected to an inductor 36 by a lead 31.
  • the resistor 34 is connected to a second inductor 38 by a lead 39.
  • the plates of a capacitor 40 are connected to the leads 3'! and 39 by leads 4
  • the inductor 36 is connected to one plate of a second capacitor 43 by a lead 44 and the second inductor 38 is connected to a third capacitor 45 by a lead 46.
  • a spark gap 41 is connected with the leads 44 and 4G by leads 48 and 49 respectively.
  • the second plate of the second capacitor 43 is connected to one side of a third inductor 50 and to one plate of a fourth capacitor 5
  • the midpoint or the inductor 50 is connected to the ground.
  • One side of an antenna coil 54 is con- 3 nected to the antenna 55 by a lead 56 and the other side of the antenna coil 54 is connected to the ground by a lead 51.
  • Figure 2 illustrates schematically the phenomena, as observed in short waves, that then occur at A in the primary circuit and at B in the secondary circuit.
  • a beat system sets up between the primary and secondary .circuits.
  • the secondary circuit At the moment C when the energy becomes zero in the primary circuit, it is on the contrary maximum in "the secondary circuit, as shown at C. Due to the coupling that exists between the resonant circuits, the secondary circuit then reacts on the primary circuit and re-ignites the spark which had become extinguished shortly before reaching point C, which corresponds to the time when the capacitor ll has completely released its charge and the cycle begins anew. The phenomenon accordingly continues until renewed .at point D. Under these conditions, the system does not operate as single wave.
  • the Wien method makes it possible, in the :known manner, to avoid this re-ignition and to obtain oscillations like those whose curves are shown in Fig 3 and are essentially linear in wave shape.
  • This method is only applicable to spark gap generators operating on sufficiently long waves. The difiiculties of de-energization occur again when dealing with waves whose length is less than about meters.
  • the present invention aims precisely at pro 'viding a process that will prevent the re-ignition as illustrated in Fig. .2 when use is made of a spark station operating on a wavelength of less than aboutlO meters.
  • Fig. 4 illustrates a spark station which is fed acrossthe resistors 32 and 34 by a voltage source 3
  • the ends of the induction coils 36 and 38 that belong to the primary circuit are connected to the ends of the induction coil 50 of the secondary circuit by the two capacitors 43 and 45,
  • An electromagnetic coupling is set up respectively between the induction coils 36 and 38 and the halves of the induction coil 5i].
  • the mid-point of the coil5fl is placed at ground potential.
  • the condensers 43 and 45 by means of which the capacitive coupling cat the vtwo circuits is efiected, are arranged with respect to the windings of the induction coils so that the electrostatic coupling of the circuits is in .reverse direction to their electromagnetic coupling. Since the voltage induced by magnetic coupling upon de-energization of .the spark gap is compensated by the voltage proceeding from the capacitive coupling, re-ignition is made impossible.
  • Fig. 2 The values shown in Fig. 2 are representative of the action in the circuit of Fig. 1.
  • the primary circuit when the voltage is at zero at point C the voltage is at a maximum in the secondary circuit as shown at point C. Due to the collapse of the secondary field a back electromotive force is exerted on the primary circuit which causes a second or induced spark across the gap 15, thereby creating a non-linear sinusoidal wave in the antenna circuit.
  • Fig. 3 are representative of the action in a neutrodyne spark gap circuit, as :showninFig. 4, whereby the voltage induced into thesecondary circuit produces a linear sinusoidal wave in the antenna circuit but back-electromotive force is cancelled due to the interaction of the electrostatic and electromagnetic fields neutralizing each other.
  • a series resonant primary circuit consisting of the inductances 36, 38, and the capacitor 40, are connccted to the spark gap 41.
  • a parallel resonant secondary circuit consisting of the inductance 50 .and the capacitor 5
  • the inductances 36 and 38 .in the primary circuit are inductively or electromagnetically coupled to the inductance in the secondary.
  • the secondary through the condensers 43 and 45, is electrostatically coupled to the primary, thereby producing a phase differ- .ence of between the primary and the secondary.
  • the inter-action between the primary and the secondary, in the present arrangement in the circuit of the invention results in .a neutrodyne action.
  • a radio transmitter of the class described employing a spark gap, a series resonant primary circuit connected to said spark gap, a parallel resonant secondary circuit, and electrostatic coup'l'ing means for coupling said primary to said secondary.
  • a radio transmitter of the class described employing .a primary circuit comprising a pair of .inductances and a condenser serially connected to a spark gap, a secondary circuit consisting of .an inductance connected in parallel with a condenser, and electrostatic means for coupling said secondary to said primary to obtain a transmitter output having a substantially linear wave shape in wavelengths shorter than about ten meters.
  • a radio transmitter of the class described employing a primary circuit comprising a pair of inductances and a condenser serially connected to a spark gap, a parallel resonant secondary circuit, and electrostatic means for coupling said secondary to said primary to obtain a transmitter output having a substantially linear wave shape.
  • a radio transmitter of the class described employing .-a series resonant primary circuit, a parallel resonant secondary circuit consisting of an inductance connected in parallel with a condenser, and electrostatic means for coupling said secondary to said primary to obtain a transmitter output having a substantially linear wave shape in wavelengths shorter than ten meters.
  • a spark gap type short wave generator comprising a series resonant circuit in the primary circuit, a parallel resonant circuit in the secondary circuit, and a capacitative coupling between said primary and the secondary circuits of the generator to restrict passage of energy from the secondary circuit to the primary circuit tending to effect re-ignition of a spark, said coupling producing a neutrodyning action.
  • a short wave generator of the class described employing a primary circuit having a spark gap connected across the output thereof, a secondary circuit having its input connected to the output of said primary circuit, certain of the elements in the primary circuit and the secondary circuit being electromagnetically coupled, and certain means for connecting the input of the secondary circuit to the primary circuit comprising electrostatic coupling means to produce a phase difference of 180 between said primary and said secondary to the end that said phase difference prevents secondary discharges across the spark gap, thereby resulting in a substantially linear output of the wave train.
  • a short wave generator of the class described employing a primary circuit having a spark gap connected across the output thereof, and a secondary circuit having its input connected to the output of said primary circuit, certain of the elements in the primary circuit and the secondary circuit being inductively coupled, and certain means for connecting the input of the secondary circuit to the primary circuit comprising capacitive coupling means to produce a phase difierence between said primary and said secondary to the end that said phase difference substantially restricts secondary discharges across the spark gap, thereby resulting in a substantially linear output of the wave train.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
US735908A 1945-06-18 1947-03-20 Neutrodyning for short waves Expired - Lifetime US2471401A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR2471401X 1945-06-18

Publications (1)

Publication Number Publication Date
US2471401A true US2471401A (en) 1949-05-31

Family

ID=9685596

Family Applications (1)

Application Number Title Priority Date Filing Date
US735908A Expired - Lifetime US2471401A (en) 1945-06-18 1947-03-20 Neutrodyning for short waves

Country Status (2)

Country Link
US (1) US2471401A (el)
FR (1) FR960987A (el)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2499155A (en) * 1947-06-30 1950-02-28 Bernard E O Neil High-frequency current generator
US2905820A (en) * 1954-07-20 1959-09-22 Bell Telephone Labor Inc Intermittent discharge pulse generators
US3214707A (en) * 1962-01-11 1965-10-26 Trw Inc Radio frequency pulse generating apparatus using an exploding wire
US3491309A (en) * 1966-10-05 1970-01-20 Laser Systems Corp Pulsed carbon dioxide laser with high voltage gradient and high gas pressure

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US768004A (en) * 1904-04-11 1904-08-16 William W Swan Space telegraphy.
US780997A (en) * 1903-02-09 1905-01-31 Cooper Hewitt Electric Co Apparatus for producing oscillatory currents.
US802432A (en) * 1904-12-16 1905-10-24 William W Swan Space telegraphy.
US824003A (en) * 1906-02-20 1906-06-19 Lee De Forest Wireless-telegraph system.
US908742A (en) * 1907-03-18 1909-01-05 Stone Telegraph And Telephone Company Space telegraphy.
US1766040A (en) * 1927-07-30 1930-06-24 Fed Telegraph Co Signal-transmitting system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US780997A (en) * 1903-02-09 1905-01-31 Cooper Hewitt Electric Co Apparatus for producing oscillatory currents.
US768004A (en) * 1904-04-11 1904-08-16 William W Swan Space telegraphy.
US802432A (en) * 1904-12-16 1905-10-24 William W Swan Space telegraphy.
US824003A (en) * 1906-02-20 1906-06-19 Lee De Forest Wireless-telegraph system.
US908742A (en) * 1907-03-18 1909-01-05 Stone Telegraph And Telephone Company Space telegraphy.
US1766040A (en) * 1927-07-30 1930-06-24 Fed Telegraph Co Signal-transmitting system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2499155A (en) * 1947-06-30 1950-02-28 Bernard E O Neil High-frequency current generator
US2905820A (en) * 1954-07-20 1959-09-22 Bell Telephone Labor Inc Intermittent discharge pulse generators
US3214707A (en) * 1962-01-11 1965-10-26 Trw Inc Radio frequency pulse generating apparatus using an exploding wire
US3491309A (en) * 1966-10-05 1970-01-20 Laser Systems Corp Pulsed carbon dioxide laser with high voltage gradient and high gas pressure

Also Published As

Publication number Publication date
FR960987A (el) 1950-04-28

Similar Documents

Publication Publication Date Title
US2415567A (en) Frequency counter circuit
US3459960A (en) High energy pulse generator utilizing a decoupling transformer
US2564005A (en) Automatic frequency control system
US2471401A (en) Neutrodyning for short waves
US2830178A (en) Pulse forming circuit
US2364756A (en) Harmonic generator
US4217468A (en) Spiral line oscillator
GB666574A (en) Improvements in the use of saturable magnetic chokes as discharge devices
US2233596A (en) Thermionic valve oscillatory circuits
US3038128A (en) Transistor blocking oscillator using resonant pulse width control
US2055208A (en) Electrical wave production
US2708241A (en) Wide gate generator
US2611092A (en) Automatic frequency control circuit
US2574647A (en) Magnetostrictive modulator
US2475621A (en) Inverter
US1968750A (en) Radio receiving system
US2588413A (en) Random frequency divider
GB1068307A (en) Circuit arrangement for the generation of a periodically fluctuating unidirectional current in an inductive load
US2901555A (en) Electromechanical amplifier
US2603748A (en) Frequency detector
US2267047A (en) Signal collecting system for radio receivers and the like
US2484209A (en) Pulsed oscillator
US1950400A (en) Frequency divider
US3317839A (en) Closed-circular annular tank circuit for spark gap transmitter
US2979614A (en) Sweep-memory voltage generator