GB749337A - Radio frequency circuits - Google Patents

Radio frequency circuits

Info

Publication number
GB749337A
GB749337A GB8111/54A GB811154A GB749337A GB 749337 A GB749337 A GB 749337A GB 8111/54 A GB8111/54 A GB 8111/54A GB 811154 A GB811154 A GB 811154A GB 749337 A GB749337 A GB 749337A
Authority
GB
United Kingdom
Prior art keywords
frequency
resonator
local oscillator
phase
oscillator
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
Application number
GB8111/54A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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
Priority claimed from US286762A external-priority patent/US2794174A/en
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB749337A publication Critical patent/GB749337A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00—Automatic control of frequency or phase; Synchronisation
    • H03L7/02—Automatic control of frequency or phase; Synchronisation using a frequency discriminator comprising a passive frequency-determining element
    • H03L7/04—Automatic control of frequency or phase; Synchronisation using a frequency discriminator comprising a passive frequency-determining element wherein the frequency-determining element comprises distributed inductance and capacitance
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07C—POSTAL SORTING; SORTING INDIVIDUAL ARTICLES, OR BULK MATERIAL FIT TO BE SORTED PIECE-MEAL, e.g. BY PICKING
    • B07C3/00—Sorting according to destination
    • B07C3/003—Destination control; Electro-mechanical or electro- magnetic delay memories
    • B07C3/006—Electric or electronic control circuits, e.g. delay lines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/18—Phase-shifters
    • H01P1/184—Strip line phase-shifters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/201—Filters for transverse electromagnetic waves
    • H01P1/203—Strip line filters
    • H01P1/20327—Electromagnetic interstage coupling
    • H01P1/20354—Non-comb or non-interdigital filters
    • H01P1/20363—Linear resonators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/201—Filters for transverse electromagnetic waves
    • H01P1/203—Strip line filters
    • H01P1/20327—Electromagnetic interstage coupling
    • H01P1/20354—Non-comb or non-interdigital filters
    • H01P1/20381—Special shape resonators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/207—Hollow waveguide filters
    • H01P1/209—Hollow waveguide filters comprising one or more branching arms or cavities wholly outside the main waveguide
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P3/00—Waveguides; Transmission lines of the waveguide type
    • H01P3/02—Waveguides; Transmission lines of the waveguide type with two longitudinal conductors
    • H01P3/08—Microstrips; Strip lines
    • H01P3/085—Triplate lines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/02—Coupling devices of the waveguide type with invariable factor of coupling
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/08—Coupling devices of the waveguide type for linking dissimilar lines or devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/08—Coupling devices of the waveguide type for linking dissimilar lines or devices
    • H01P5/10—Coupling devices of the waveguide type for linking dissimilar lines or devices for coupling balanced lines or devices with unbalanced lines or devices
    • H01P5/107—Hollow-waveguide/strip-line transitions
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/12—Coupling devices having more than two ports
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/12—Coupling devices having more than two ports
    • H01P5/16—Conjugate devices, i.e. devices having at least one port decoupled from one other port
    • H01P5/18—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers
    • H01P5/184—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers the guides being strip lines or microstrips
    • H01P5/187—Broadside coupled lines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/247—Supports; Mounting means by structural association with other equipment or articles with receiving set with frequency mixer, e.g. for direct satellite reception or Doppler radar
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/06—Details
    • H01Q9/065—Microstrip dipole antennas

Landscapes

  • Electromagnetism (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Measurement Of Resistance Or Impedance (AREA)
  • Constitution Of High-Frequency Heating (AREA)
  • Waveguides (AREA)
  • Waveguide Connection Structure (AREA)
  • Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
  • Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)

Abstract

749,337. Automatic frequency control systems. STANDARD TELEPHONES & CABLES, Ltd. March 19, 1954 [March 26, 1953], No. 8111/54. Class 38 (4). [Also in Groups XL (b) and XL (c)] A microwave or U.H.F. radio receiver incorporating automatic frequency control comprises transmission lines of the so-called " lineabove-ground" type. Such transmission lines are described in Specification 711,578, [Group X], and consist of a base or " ground " conductor 3, Fig. 2, extending beneath the whole circuit and " line " conductors 1, 2, Fig. 2; 32, 33, 45, 46, &c., Fig. 7, .spaced from the ground conductor by a sheet of dielectric 4 of thickness equal to a small fraction of #/4, where # is the working wavelength. Couplings having directional properties are formed between pairs of lines by the closely-spaced parallel sections 22, 23, 24 (see Group XL (b)). Power from a local oscillator 41 coupled into lines 32, 33 by the coupling sections 22, 23 is mixed with the signal from an antenna 26 in a circuit 34, 35, the resultant intermediate frequency being fed to an amplifier 40 (see Group XL (c)). A fraction of the power from the local oscillator 41 is fed through an attenuator 49 to the coupling 24 and is divided between the branches 50, 51, whence it is reflected by the cavity resonator 54 and short-circuit 52 into the branch 62. The amplitude and phase of the power reflected from the branch 50 depends upon the tuning of the resonator 54 which is periodically varied at the rate of a few kc/s. by a low-frequency oscillator 58. When the resonator has a mean frequency equal to the desired frequency of the local oscillator 41 it behaves like a short-circuit and the fractions reflected into branch 62 from the two branches 50, 51 will have the same phase. Thus a maximum rectified output is obtained from crystal 55a. Under these circumstances the output of a phase discriminator 57 connected to the L.F. oscillator 58 and the crystal 55a is zero. If, however, the frequency of the local oscillator 41 departs from the desired value a component of the frequency of the oscillator 58 appears in the output of the crystal 55a and the discriminator 57 produces a D.C. output which is arranged to be of the proper sign to correct the frequency of the local oscillator. A phase-shifter 59 enables the relative phases of the waves supplied to the resonator 54 and the discriminator 57 to be adjusted to compensate for phase shifts introduced by the resonator 54 and an amplifier 56 interposed between the crystal 55a and the discriminator 57.
GB8111/54A 1952-05-08 1954-03-19 Radio frequency circuits Expired GB749337A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US286762A US2794174A (en) 1952-05-08 1952-05-08 Microwave transmission systems and impedance matching devices therefor
US324545A US2859417A (en) 1952-05-08 1952-12-06 Microwave filters
US749337XA 1953-03-26 1953-03-26
US3159253A 1953-11-13 1953-11-13

Publications (1)

Publication Number Publication Date
GB749337A true GB749337A (en) 1956-05-23

Family

ID=32329982

Family Applications (7)

Application Number Title Priority Date Filing Date
GB2013/53A Expired GB726067A (en) 1952-05-08 1953-01-23 Microwave coupling arrangements
GB12110/53A Expired GB761761A (en) 1952-05-08 1953-05-01 Microwave filters
GB12111/53A Expired GB761762A (en) 1952-05-08 1953-05-01 Microwave transmission systems and impedance matching devices therefor
GB12114/53A Expired GB761765A (en) 1952-05-08 1953-05-01 Microwave transmission line
GB31595/53A Expired GB761778A (en) 1952-05-08 1953-11-13 Microwave filters
GB8111/54A Expired GB749337A (en) 1952-05-08 1954-03-19 Radio frequency circuits
GB14706/56A Expired GB809482A (en) 1952-05-08 1956-05-11 Microwave lines and high q filters

Family Applications Before (5)

Application Number Title Priority Date Filing Date
GB2013/53A Expired GB726067A (en) 1952-05-08 1953-01-23 Microwave coupling arrangements
GB12110/53A Expired GB761761A (en) 1952-05-08 1953-05-01 Microwave filters
GB12111/53A Expired GB761762A (en) 1952-05-08 1953-05-01 Microwave transmission systems and impedance matching devices therefor
GB12114/53A Expired GB761765A (en) 1952-05-08 1953-05-01 Microwave transmission line
GB31595/53A Expired GB761778A (en) 1952-05-08 1953-11-13 Microwave filters

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB14706/56A Expired GB809482A (en) 1952-05-08 1956-05-11 Microwave lines and high q filters

Country Status (6)

Country Link
US (2) US2859417A (en)
BE (4) BE533239A (en)
CH (4) CH316574A (en)
DE (3) DE1036950B (en)
FR (13) FR1072220A (en)
GB (7) GB726067A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3166723A (en) * 1961-03-06 1965-01-19 Micro Radionics Inc Variable directional coupler having a movable articulated conductor
EP0560503A1 (en) * 1992-03-09 1993-09-15 Lk-Products Oy Electrical filter
US5432489A (en) * 1992-03-09 1995-07-11 Lk-Products Oy Filter with strip lines
EP0669671A1 (en) * 1994-02-24 1995-08-30 Hughes Aircraft Company Cavity matched hybrid coupler
EP1494316A1 (en) * 2003-07-02 2005-01-05 Thomson Licensing S.A. Dual-band antenna with twin port

Families Citing this family (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3011009A (en) * 1956-06-28 1961-11-28 William J Titus Structural components for aircraft or the like
US2962716A (en) * 1957-06-21 1960-11-29 Itt Antenna array
US2954468A (en) * 1958-03-25 1960-09-27 Thompson Ramo Wooldridge Inc Microwave filter and detector
US2977484A (en) * 1958-09-10 1961-03-28 Rca Corp Logic circuit for a radio frequency carrier information handling system
US2976498A (en) * 1959-08-03 1961-03-21 Electronic Specialty Co Radio frequency filter
US3104362A (en) * 1959-08-27 1963-09-17 Thompson Ramo Wooldridge Inc Microwave filter
US3111634A (en) * 1960-05-13 1963-11-19 Singer Inc H R B Strip transmission line modulator
US3156880A (en) * 1960-08-04 1964-11-10 Melpar Inc Lumped constant filter
NL269350A (en) * 1960-09-20
US3136946A (en) * 1960-09-29 1964-06-09 Itt Microwave resistance measuring system including thermoplastic microstrip coupler
US3164791A (en) * 1961-05-05 1965-01-05 Melpar Inc Strip line hybrid ring
DE1244257B (en) * 1961-05-25 1967-07-13 Emi Ltd Circuit arrangement for the reaction-free coupling of two voltages to form a total voltage with three strip conductors opposite a grounded common conductor
US3153209A (en) * 1962-06-18 1964-10-13 Julius A Kaiser Microwave filter utilizing two resonant rings and having terminals permitting use to band pass or band reject
US3345589A (en) * 1962-12-14 1967-10-03 Bell Telephone Labor Inc Transmission line type microwave filter
US3235820A (en) * 1963-08-12 1966-02-15 Hughes Aircraft Co Electrically variable phase shifter
US3228030A (en) * 1965-06-11 1966-01-04 Gen Dynamics Corp Shielded antenna
JPS5130421B1 (en) * 1965-09-30 1976-09-01
DE1297719B (en) * 1967-01-12 1969-06-19 Stassfurt Fernsehgeraete Tunable line circuits for high-frequency electrical oscillations in stripline technology
US3548344A (en) * 1967-07-28 1970-12-15 Varian Associates Stripline gain equalizer
US3605045A (en) * 1969-01-15 1971-09-14 Us Navy Wide-band strip line frequency-selective circuit
US3688225A (en) * 1969-05-21 1972-08-29 Us Army Slot-line
US3623112A (en) * 1969-12-19 1971-11-23 Bendix Corp Combined dipole and waveguide radiator for phased antenna array
US3668569A (en) * 1970-05-27 1972-06-06 Hazeltine Corp Distributed-constant dispersive network
US3921177A (en) * 1973-04-17 1975-11-18 Ball Brothers Res Corp Microstrip antenna structures and arrays
US3909755A (en) * 1974-07-18 1975-09-30 Us Army Low pass microwave filter
JPS5336284B2 (en) * 1974-09-06 1978-10-02
US4035807A (en) * 1974-12-23 1977-07-12 Hughes Aircraft Company Integrated microwave phase shifter and radiator module
DE2742779C1 (en) * 1977-09-23 1999-07-08 Raytheon Co Strip conductor mixer circuit
FR2460049A1 (en) * 1979-06-25 1981-01-16 Labo Electronique Physique BANDWHEEL FILTER FOR A HYPERFREQUENCY TRANSMISSION LINE AND A MICROWAVE TRANSISTOR POLARIZATION CIRCUIT COMPRISING THE FILTER
FR2487588A1 (en) 1980-07-23 1982-01-29 France Etat DOUBLE REPLIES IN PLATES FOR VERY HIGH FREQUENCY AND NETWORKS OF SUCH DOUBLETS
US4316160A (en) * 1980-07-28 1982-02-16 Motorola Inc. Impedance transforming hybrid ring
FR2494942B1 (en) * 1980-11-21 1985-07-12 Radiotechnique Compelec TELEVISION RECEIVING HEAD
EP0068345A1 (en) * 1981-06-25 1983-01-05 Communications Satellite Corporation Symmetrical coupled line coplanar waveguide filter
US4420839A (en) * 1982-03-30 1983-12-13 Bunker Ramo-Eltra Corporation Hybrid ring having improved bandwidth characteristic
GB2153155B (en) * 1984-01-24 1987-04-15 Secr Defence Improvements in or relating to microwave filters
US4610032A (en) * 1985-01-16 1986-09-02 At&T Bell Laboratories Sis mixer having thin film wrap around edge contact
GB2189652B (en) * 1986-03-26 1990-01-24 Plessey Co Plc Adaptor for connecting a coaxial transmission line to a parallel plate transmission medium
US4937585A (en) * 1987-09-09 1990-06-26 Phasar Corporation Microwave circuit module, such as an antenna, and method of making same
US5093640A (en) * 1989-09-29 1992-03-03 Hewlett-Packard Company Microstrip structure having contact pad compensation
FR2670327A1 (en) * 1990-12-06 1992-06-12 Europ Agence Spatiale HYPERFREQUENCY HYBRID COUPLER WITH 3XN INPUTS AND 3XM OUTPUTS, IN PARTICULAR COUPLER 3X3.
US5334961A (en) * 1991-08-12 1994-08-02 Matsushita Electric Industrial Co., Ltd. Strip-line type bandpass filter
DE19636890C1 (en) 1996-09-11 1998-02-12 Bosch Gmbh Robert Transition from a waveguide to a strip line
JP2001136003A (en) 1999-11-05 2001-05-18 Murata Mfg Co Ltd Dielectric filter, dielectric duplexer and communication unit
KR101308301B1 (en) * 2006-03-01 2013-09-17 알카텔-루센트 유에스에이 인코포레이티드 Meta-material filter for use in a base station of a wireless communications system
US7873329B2 (en) 2006-04-25 2011-01-18 ThruVision Systems Limited Transceiver having mixer/filter within receiving/transmitting cavity
WO2007125326A1 (en) 2006-04-25 2007-11-08 Thruvision Limited Radiation detector
US7616058B1 (en) 2006-08-28 2009-11-10 Raif Awaida Radio frequency power combining

Family Cites Families (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2274346A (en) * 1938-01-27 1942-02-24 Telefunken Gmbh Frequency selective transmission line
BE434940A (en) * 1938-06-22
DE866061C (en) * 1940-09-03 1953-02-05 Blaupunkt Elektronik G M B H Device for adjusting the phase position of an electromagnetic oscillation in a waveguide
GB578911A (en) * 1941-08-26 1946-07-17 Gen Electric Co Ltd Improvements in electrical apparatus adapted to operate at very high frequencies
GB579414A (en) * 1941-10-15 1946-08-02 Standard Telephones Cables Ltd Improvements in or relating to electric wave filters
FR899350A (en) * 1942-11-06 1945-05-28 Telefunken Gmbh Improvements to tubular lines for very short waves
NL217682A (en) * 1942-12-31
GB579782A (en) * 1943-01-08 1946-08-15 Standard Telephones Cables Ltd Phase changers
DE871324C (en) * 1943-02-07 1953-03-23 Julius Pintsch K G Arrangement to compensate for changes in impedance occurring at points of interference along ultra-high frequency transmission lines
FR964835A (en) * 1943-06-23 1950-08-25
US2543425A (en) * 1945-06-14 1951-02-27 Malcom W P Strandberg Squeezable wave guide for line stretching
FR950844A (en) * 1945-06-19 1949-10-07 Hazeltine Corp Impedance matching device
GB608494A (en) * 1945-07-10 1948-09-16 William Arthur Johnson Improvements in and relating to the waveguide transmission of electromagnetic waves
US2637813A (en) * 1945-08-20 1953-05-05 Rca Corp Balanced microwave detector
US2479673A (en) * 1945-08-20 1949-08-23 Rca Corp Directional microwave transmission system having dielectric lens
US2587590A (en) * 1946-07-26 1952-03-04 Sperry Corp Ultrahigh-frequency apparatus
NL72534C (en) * 1948-04-26
GB655803A (en) * 1948-08-30 1951-08-01 Cossor Ltd A C Improvements in and relating to transmission lines for radio-frequency electric oscillations
US2710917A (en) * 1948-09-14 1955-06-14 Itt Dual band antenna system
US2784381A (en) * 1948-10-05 1957-03-05 Bell Telephone Labor Inc Hybrid ring coupling arrangements
GB670405A (en) * 1949-04-22 1952-04-16 British Thomson Houston Co Ltd Means for controlling a member of great length for use with wave guides
US2639325A (en) * 1950-03-24 1953-05-19 Bell Telephone Labor Inc Hybrid ring
DE821035C (en) * 1950-09-10 1951-11-15 Gutehoffnungshuette Oberhausen Lock pocket for pit stamp
BE518175A (en) * 1951-05-23
US2721312A (en) * 1951-06-30 1955-10-18 Itt Microwave cable
NL176506B (en) * 1952-03-05 Fujitsu Ltd GAS DISCHARGE DISPLAY DEVICE.
US2789210A (en) * 1952-12-30 1957-04-16 Sylvania Electric Prod Mixing circuit for microwave frequencies

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3166723A (en) * 1961-03-06 1965-01-19 Micro Radionics Inc Variable directional coupler having a movable articulated conductor
EP0560503A1 (en) * 1992-03-09 1993-09-15 Lk-Products Oy Electrical filter
US5432489A (en) * 1992-03-09 1995-07-11 Lk-Products Oy Filter with strip lines
EP0669671A1 (en) * 1994-02-24 1995-08-30 Hughes Aircraft Company Cavity matched hybrid coupler
US5499001A (en) * 1994-02-24 1996-03-12 Degun; Joginder S. Cavity matched hybrid coupler
EP1494316A1 (en) * 2003-07-02 2005-01-05 Thomson Licensing S.A. Dual-band antenna with twin port
FR2857165A1 (en) * 2003-07-02 2005-01-07 Thomson Licensing Sa BI-BAND ANTENNA WITH DOUBLE ACCESS
US7057568B2 (en) 2003-07-02 2006-06-06 Thomson Licensing Dual-band antenna with twin port
CN1585191B (en) * 2003-07-02 2010-08-18 汤姆森许可贸易公司 Dual-band antenna with twin port

Also Published As

Publication number Publication date
GB809482A (en) 1959-02-25
BE527584A (en)
US2859417A (en) 1958-11-04
DE1002828B (en) 1957-02-21
GB761778A (en) 1956-11-21
CH317717A (en) 1956-11-30
FR70420E (en) 1959-05-06
GB726067A (en) 1955-03-16
FR65726E (en) 1956-03-12
CH328921A (en) 1958-03-31
FR65729E (en) 1956-03-12
FR66218E (en) 1956-06-05
DE1042048B (en) 1958-10-30
BE533239A (en)
FR1072220A (en) 1954-09-09
FR65725E (en) 1956-03-12
US2874276A (en) 1959-02-17
DE1036950B (en) 1958-08-21
BE519797A (en)
FR69959E (en) 1959-01-30
CH316574A (en) 1956-10-15
GB761761A (en) 1956-11-21
FR66227E (en) 1956-06-05
FR68805E (en) 1958-06-10
GB761762A (en) 1956-11-21
GB761765A (en) 1956-11-21
CH347233A (en) 1960-06-30
FR66225E (en) 1956-06-05
FR68853E (en) 1958-06-11
FR66221E (en) 1956-06-05
FR69008E (en) 1958-08-27
BE518176A (en)

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