US1997111A - System of stroboscopic radiogoniometry - Google Patents

System of stroboscopic radiogoniometry Download PDF

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Publication number
US1997111A
US1997111A US578192A US57819231A US1997111A US 1997111 A US1997111 A US 1997111A US 578192 A US578192 A US 578192A US 57819231 A US57819231 A US 57819231A US 1997111 A US1997111 A US 1997111A
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current
frames
aerials
lamps
tube
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US578192A
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Hardy Rene Jean
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
    • G01S1/02—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves

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  • (mast-+11 f invention relates toradiodirection findmg apparatus of the kindin which a stroboscopic devicerotates synchronously .with a group of two receiving frameaerialsarranged at right angles 5 to each other and iscilluminated byithe amplified current from the aerials. 3. l r The object of the invention-is to provideapparatus-of this kind whichwillpe'rmit the determination of the.
  • radio-direction-finding apparatus of the kindire ferred to above wherein the two receiving frame aerials are suitably tuned and connected respectively to impedances which comprise. identical windingslwound reversely and" arranged to in fluencea tuned common impedancev connected through one or more reinforcing or amplifying stages'to impedances or. a group of. impedances', combined 'ifdesired with amplifying devices, controlling the illumination of thesluminoussources of the stroboscopicdevice. In order that the.
  • FIG. 1 is a diagrammatic general view showing the, method of action of rotating orthogonal frame aerials on the luminous sources for lighting or extinguishing the luminous sources to give a stroboscopic effect.
  • Fig-2 is a diagrammatic elevation showing .the arrangement of index anddial of the stroboscopic device on the rotating frames. i l
  • Fig. 3 isa detail of the rotating indexp 1 i Fig. ishows diagrammatically howwany uncertainty which arises at 180 is removed. 40.
  • V L Fig. 6 is .a generalview'showing diagrammatically/the rotary frames, and amplifying and in dicating devices.
  • j 1 i Fig. l shows the curves of mten'sityofreception of the frames, according to their orientation;
  • Fig. 8 is a series of explanatory curves
  • Fig.3. is a diagram showing the angular
  • FIG. 5 is a diagrammatic detail of aldevice-difflectionsofthe lamp illuminations indicating the inductances 6, i; whichjarewoundzin contrary directions. V, l
  • The'self induc'tancese, i, are arranged'close to; a self inductance B tuned to the same wave length, and connected to: the grid 9 of .anSamplia5.
  • IQ for example the plate A [of which comprises .inits circuit a self inductance E Z'tunedto'the same wave length. as 8;
  • the self. inductance l 2 is arranged so asto influence thegtwo self inductances l3, l4.
  • the impedance [3 is in serieswith a uni-directi'onal resistor .15, and a resistance i6 "forming part of the'grid circuit of theivalves li, l5 b-eing an. element intended tofirectify high frequency. current transmitted by impedance i3. :Fcr-this purpose for example may be used a galena crystal.
  • Anlimpedance- I8 is interposed betweenthe'plate .of the valve 1 land an illuminating device such for example as a neon tube I9.
  • a circuit come posedof a resistance .20 and a capacity resistance 2! shunt with the neon tube i9. Due to this device, when there is an equilibrium ,ofcurrent. in the frames 1 and 2, the currents passing through the impedances 6 and 1 are equal and of contrary direction, so that their eii'ectcn the impedance 8counter-balarices each other.
  • inductance l3 is impressed on inductance l3.
  • the sensitivity may be made as great as desired, for example by a'suitable increase of the number of amplifying stages, determining the illumination of the neon tube H! bythe absence of the alterhating current'in 8, and the extinctionof this tube whenthere is an alternating current in "8.
  • the impedance l l which', like the impedance I3, is coupled to l2,'is' connected to the grid of thelvalve 22, :theplate' of which also comprises a-choke 23,-connected to, an illuminating device such .as neon tube 24 similar .to the tube 19 across whichflikethe tubel9, is connected :9. capacity and resistance .25.
  • the grid potential oflthe valve 22" is such that said valvei'operates as adetector and the plate potential is such that the illumination of the tube 24 is producedwhen there is a high frequency current in 8.
  • both frames l and 'Z receive for instance the current of said emitting station.
  • the currents received bysaid-frames are in opposition,-and if the frame ltfo'r instance'is in the direction of the emitting station, the induction will reach a maximum at 8, since no'current flows through the frame 2.
  • the frames 1-2 will be mounted on :a common axis .26 which is vertically supported, as diagrammatically'shown in Fig. .2, in order'that they may rotate in suitable bearings whichare There may be used in fact an are or a filament lamp ora not shown in the drawings.
  • a pulley 27 suitably connected with any source of power which is not shown in the drawings the frame unit may receive a rotary movement with a suitable velocity, and an index-hand 28 fast on axis 25 travels across a fixed scale 29.
  • Suitably arranged and insulated conductor rings 30 are mounted in any desired number on the axis 26.
  • Said rings which are'suitably connected with the'frames I and "2, are provided with brushes of any suitable construction which are connected to an amplifying device diagrammatically shown at 3i, and which may be provided with the arrangement shown in Fig. 1 for controllingv the illumination of the neon tubes i9 and 24.
  • the tube 24 flashes when a frame passes in the direction of I the emitting station, so that the ample in' Fig. 6.
  • the amplifier re-' ceives a current whichgrowsmore and more intense as the rotation of' the frame progresses, and'reaches a, maximum which is attained when the direction of oneside of theframe is in line with the vemittingstation. Then by using the maximum receiving current for illuminating the tubeifi, a momentaryflillumination of said tube is obtained forevery revolution when the frame is approximately in the direction of the emitting station.
  • the device shown in Fig. 2 comprises two frames with a directional effect
  • there will be two .reception curves which will give two points of the same value when two bisecting lines only pass in the directionof the emitting station, as will be more particularly explained hereinafter.
  • Both positions will be the positions in which the frames with a directive effect are in line with 'the emitting station, (as the index is in the bisecting line of the. planes of the frames).
  • the neon tube 24 indicates the bisecting line which lies in the direction of the emitting station, since said tube2- l will flash on'eac'h of said 'bisecting lines in anangle of approximately 45 on each side as will be explained hereinafter.
  • a fixed dial36 for example of glass, has two scales 31', 38 over the "whole'of the circumference, andl in a; lower plane the index28 .is fitted ch -the spindle;26..which; is rotatable in a plane parallel to thatmf the dial36.
  • the index 28 comprises/"two neon tubes. 39, 40 connected electrically by; a collector 4I to the amplifier 3
  • counterflweightfig counterebalances the'index in order to; maintain-rotation, without vibration, in all planes;
  • two slots 43 3 116,344, in the. indexj permit. an observer. placed above the dial to see on suchdial two luminous beams such as @45, 46; coming from the n'eon tubes 28 and 25 whenfthey are tilluminat'ed, and 0ccupying a "different position on the scales3l, 38,
  • anykind of directional frameaerial may be used provided that the reception, according to the orientatiomgives a maximum in one direction;
  • One-type of frame aerial; already known, and described as anjexample, is shown in Fig l, Where ,45 is the frame proper, 46 a ,variable "resistance. grounding the center ofthe frame, and 41. is; arr-amplifying valve, the grid 48 ,of which is connectedat 49 tothe' frame, ; The t,uning.sys-vv tem ;is composedi of two equal condensers grounded through a fixed condenser 5
  • 55 and 5B are two'coil's ofthe same value, each ofwhich is also perpendicularly farrang'ed and Wound 'in'the same direction as the winding of the corresponding large frame, andeachbeing arranged in'the same corresponding plane.
  • The'said impedances 58 and 59 form two strictly identical perpendicular windings, and when both impedances are so orientated that one of them'is in, the direction of. the emitting station,
  • this coil will be traversed by a maximum current, by any cur- Whilethe other will not be traversed rent, and vice versa.
  • the wave collector is constituted by two frames I"
  • the two small frames or coils ii and 72 are exactly identical with each other and each is inthe same plane as the winding i or 2 with which. it is in series.
  • the coil l3 of two perpendicular impedances constitutes a search coil and can rotate with the axis "M which comprises at its lower part an index 75 indicating the direction of a bisector of the impedance '93, this index 55.1-0- tates with respect to a fixed dial it illuminated stroboscopicallyduring its rotation by glow discharge'tubes El and iii dependent onthe amplifier.
  • the center point E9 of the winding of the frame 73 is groundedat 39 through an adjustable resistance 8 i
  • the tuning of the frame '53 is accomplished 'by a. double condenser 82, the center point of which is grounded at 8-9 through the capacity 83.
  • One of the extremities'of the windings of. the frame 73 is connected to the grid 34 of an amplifying valve 85.
  • pendicular, windings may be considered as the wave'collector of the amplifier, for it rotates in an artificial field which has thesame orientation as the actual field.
  • thisframe isdouble, composedof two perpendicular windings in series, and it may be considered as giving the difierential action of two identical frames of which the windings were perpendicular. There is'thus on the grid 8d the resulting action or the two perpendicular windings of 13.
  • the condenser' 94- transmits this current of intermediary frequency to the amplifying valve 95; a certain number of amplifying stages forthis intermediatefrequency may also be provided, if desired;
  • the valves 96 and 91.amplifysaid current'stilljurther and in seriesiwith'the-anode of 9T is mounted a'final resonant'circuit 98. w I
  • circuit 98 of the valve 91 there is exactly the same phenomenon; that is-to say, when there is no alternating potential on the grid '84 there is no alternating current'in the impedance ofthecircuitiia; but when thereis'the least high "frequency potential on the grid 84, there is a strongly amplified current in the impedance of the circuit'98.
  • the alternating current is only zero during a very short momentjtwice for each rotation o f'th impedances l3, and that, on the other hand, for the remainder of the time there is an alternating current passing; Furthermore, through two maxima of amplitude, these maxima are produced a littlebefore and a little after one ofthe positions of zero current and always on each'side'of the'same zero, that is to say, in pairs, or again, at every369 of the rotation of winding 13
  • Theimpedance of the tuned circuit 98 is divided into two partsione of which is coupled with'another impedance 99 forming part of the grid circuit of a final valve 100.
  • the impedance $9 delivers to a resistance and acts on the grid of; [8H in series with'a rectifying device I ill which works as above described for the amplifier-of Fig. l.
  • Any alternating current'in the coil 99 corresponds to a lowering of the mean potential of the grid'of valve M0 or, what is'exactly the same, any alternating "current, 'even of very low amplitude, acting on the grid 84 of the inputvalve 85, corresponds to a lowering of the mean potential of the grid of valve Hill and td'the extinguishment of the neon tube T! in series with the anodeof valve Him Y v V I
  • a chok e coil I92 may be usefuland the neon tube 1'! will be conveniently shunted by a .ca-
  • the second part ofthe impedance of the net workSlB is coupled with an impedance I04 which acts on the grid of a valve I05 acting as a-detector,- and also comprisinganiimpedance I06 and ame'on V V h V i 997 111 tube I as shunted byacapacityresistahce aha m in series-with the anode'of thevalve' [05. "It is easy to adjustthe value ofthe-plate our? 'rent'of the valve, I05 in ordentolightthe neon tube 18 as soon as a certain minimum'amplitude of the "alternating currentat'llld is reached, the, tube I08 remaining darkbelow saidamplitude.
  • the a valve 195 works exactly in the same manner as'the valve. 22 in Fig. 1 which-'detects every alternating' current acting "on' the grid? Through theirrepeated “lighting and extinguishing the tubes 11 and 118 indicatethe direction of 'the emitting-station on which the amplifier "is acs "cordedk'Tube 'il islighted whenno current passes'sgi. e, when it is traversed 'byboth bisecting lines;one of which is in' thedirection of theemitting station, andtheother thes'ame direction but turnednearly- 180?. i
  • the tube 18 is lighted at points closeto and en bothfsides of the bisecting line which really in-' dicates the direction oftheemitting' station, thus permitting thedetermination of said direction.
  • -A closeexamination ofthe hereinafter described reception curves enables "one, to understand the each of said frames, one "of which isc-rientated in' the axis 199 (Fig. 7) and the other the axis Ht, :are circles H
  • Each o'fsaid' two small perpendicular frames 'formingthe rotary unit receivescurrents as' 'the frames rotate and, said currents ma'ybe repre- M99420 (Fig. 8),'spaced90 apart-and having the same shape, and possessing as in i2! and I22 (Fig. 8) points of the same value corresponding to angles of the same value between the emitting station and each of the frames, vizJ-fanglesbf 45 1;
  • This resulting curve therefore presents ,two' .points .Ml, Hid-of zero current, which correspond to the points of same value [46 and ltfl of the .two reception curves (Fig. 8)- 'or the points e and f of the curvesg andh of Fig; 7 These two. points Where the two frames in their rota- "tion'pass through .a'similar amplitude value c0r-. respond to the passage of a bisector in the direction of the emitter. r
  • the index carrying both neon tubes rotates with both perpendicular windings secured fast on ,the rotation axis 61in Fig. 6.
  • the rotation speed may be for instance 600 R.,P. M. so that each of the neon tubes Tl and T'2 will flash twenty times to the second under the dial 36 in Fig. 9,
  • Said frequency ofthe flashes is suificientin order that, all theflash'es, in spite of being very short and instantaneous, seem tofthe eye to form only aconstantly luminous line which continually gives the. direction ofthe emitting station 131 (Fig.9).
  • the stroboscopic efieet is preferably produced through a. continuous rota tion of the axis with a sufficient speed.
  • the flashing of thetubeT-2 which-eliminates the-uncertainty neednot be as short, as for the other tube and infactit lasts'for acertain time i which may be. controlled and adjusted; by the V valuepof the plate current of the detector valve I05 controlling the tube of the coupling of the coils 184 (Fig. 6),. 1 r
  • the actionof parasitical currents has no effect on 'theindication of the direction, for they pro-' turn only flasheswhich have nosynchronism with the rotation ofthe'index.
  • the immediate determination of the position of any emission may takeplaceby asimple tun.- ing of the amplifier on said emission. It is then very easy, by triangulation and by determination of the position of different, emitters, to determine the'position of areceiving; device, for instance in the aeronautics.
  • a radio-goniometric receiver is in a position pled in common to said first-mentioned-impedances, a pluralityof lamps, circuitsior said lamps operatively associated with said common impedance andmeans in each of said circuits for con trollingthe current flow through the lamps,
  • Radio-direction finding apparatus comprising two rotatable receivingfrarne aerials disposed at an angle toeach other, means for tuning said aerials, and comprising s1ibstantially identical impedances woundinversely with-respect to each other, a shaft carrying. said aerials, a balanced radial index-disposed. onfsaid: shaft aerials; and rotatable therewith; slots on said index, along,.-an
  • Radio direction finding apparatus comprising two fixed receiving frame aerials of;large dimensions disposed at an angleto each other, two smallercoils disposed at a corresponding angle to eachother 1 and to which said aerials are connect- [ed a third coil disposed for rotation within said smal1; coils;v means for tuning said aerials, means for tuningand amplifying the" output of said third coil, aplurality of lamps, and means for diflierentially connecting saidlamps with said third coil: in such;m anner that one of the lamps is illuminated only when the; current 1 flowing through the coilis ,zero, and the other lamp bei g, illuminated only when the cur-rent flowing,
  • angle to each other means for eifecting an apparentrotation of the fleld induced in said aerials, acircuit associated with said means, and containing means for displacing the maximacf said aerialsrela- ,tive to each other, a plurality of lamp's,,circuits forlsaiddamps operatively connected with said iiirst, circuit, means in each-of said circuits for controlling the current flow through the lamps,
  • Radio direction,indicatingapparatus, -com-' prising loop aerials disposed at an angle to each other, means for tuning said aerials on an emitter, means for effecting anapparent rotation of the field induced in said-aerials, a circuit associated with said means and containing means for displacing the maxima' of said aerials relative to each other, a plurality of lamps, meansfor rotating said lamps at a speed proportional to that of the rotating fieldya transparent scale disposed above said lamps, circuits for said lamps operatively connected with saidflrst-mentioned circuit, and means in each of said lamp circuits for controlling the current flow through the lamps, whereby one of the lamps is energized only when the current flowing through said aerials is equal,
  • the said first-mentioned circuit being capable of dis placing the maxima of said aerials relative to each other in such manner that the flashes of that one of the lamps corresponding thereto occur closely adjacent to each other on the scale,
  • -'6.Radio directionindicating apparatus comprising loop aerials disposed at an angle to each other, means for tuning said aerials on an emitter, -means for effecting an apparent rotation of the field induced in said aerials, acircuit associated with said means, and containing means for displacing the maxima of said aerials relative to each other,'a.plurality of lamps, circuits for saidslamps .operatively connected with said first circuit, means in each of said circuits for con trolling the current flowjthrough the lamps,
  • one of the lamps is energized only when the current flowing through said aerials is equal, and the other only when the current through said aerialsis asymmetrical and approaches a maximuin in one of the 'aerials a pointer rotatable at aspeed proportional to'the rotating field and illuminated by' the lamps, to indicate the direction' of the emitter, the means in the lamp cir-' cuit's, as an incident to current flow through the aerials, causing two flashes of eachlamp for each 'rotation'of the'field of the aerials, the means in the first-mentioned circuit causing the flashes for that one of. the lamps which corresponds to themaximainl the aerials tofbe closely'adjacent to each other; and one closely-on each side' of that flash of the other lamp which occurs when the pointer is'directed towards the emitter, the
  • Radio direction indicating apparatus com prising loop aerials disposed at an angle to each other, means for tuningsaid aerials on an emitter, meansfor eiiecting an apparent rotation, at.
  • Radio direction indicating apparatus comprising a directional antenna, the coils of which are disposed at an angle to each other, the directional antenna causing the maxima of said coils tube; displaced relative to, but closely adjacent eachother, means for turning said coils on an emittenmeans for effecting an apparent'rotation at desired speed of the field induced in said coils, a plurality of lamps, circuits for said lamps operatively coupled with said coils, means. in each of said circuits'for controlling the currentflow'v through the lamps, whereby. one of the lamps is energized-only when the current flowing through said aerials is equal, and the other only when the current through said aerials is asymmetrical.
  • a pointer rotatable at a speed proportional to the rotating field and illuminated by the lamps, to indicate the direction of the emitter, the displacement of the maxima beingsuch that'the flashes of the-lamp corresponding thereto occur closely adjacent, to each other during a revolution of the-rotating field, one on each side of that fiash of the other lamp which occurs when the pointer is directed-towards the emitter.
  • Radio direction indicating apparatus comprising a directional antenna consisting'of fixed loop aerials disposed at an angle to each other, means for tuning said loop aerials to an" emitter, auxiliary loop aerials, connected one to, each of said first mentioned loop aerials, and disposed with the same angular relation relative to each other, a coil consisting of two, portions which have the same angular-relation to each other as do the aerials, rotatably disposed within and along the axis of saidauxiliaryaerials, ashaft forssaid coil means for connecting the mid-portion; of said coil to the ground, means for tuning said coil, the directional antenna causing the maxima of said aerials to be displaced relative to butt-closely adjacent each other, a plurality of lamps, circuits for said lampsioperatively coupled to said auxiliary aerials through said coil means in each of said circuits, for controlling thecurrent' flow through the lamps, whereby one of the lamps is energized only when the .currentflowing through said aerials is equal, and the other only
  • cent positions, onev on eachside of thatflash of the otherv lamp which occurs when the pointer is directed towards the emitter the "rotational speed of the coil being such that the lamps produce afstroboscopic' efiect.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Audible And Visible Signals (AREA)
  • Chairs Characterized By Structure (AREA)
  • Discharge-Lamp Control Circuits And Pulse- Feed Circuits (AREA)
US578192A 1930-12-04 1931-11-30 System of stroboscopic radiogoniometry Expired - Lifetime US1997111A (en)

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FR633773X 1930-12-04

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468109A (en) * 1945-03-19 1949-04-26 Standard Telephones Cables Ltd Direction finder
US8179330B2 (en) * 2009-05-07 2012-05-15 Intel Corporation Omnidirectional wideband antenna

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE767320C (de) * 1936-04-02 1952-05-26 Lorenz A G C Einrichtung zur Feststellung reflektierender Objekte
DE767321C (de) * 1936-12-25 1952-05-26 Lorenz A G C Verfahren zur gleichzeitigen Richtungsbestimmung mittels Feldstaerke-vergleich bei Entfernungsmessungen mittels Impulsen
US2459162A (en) * 1940-11-16 1949-01-18 Harvey C Hayes Acoustical sound locating device
US2473974A (en) * 1944-05-18 1949-06-21 Schuck Oscar Hugo Underwater sound detecting and indicating system
DE1273357B (de) * 1959-02-13 1968-07-18 Ibak Helmut Hunger Verfahren zum Absuchen eines Seegebietes mittels eines Unterwasserfernsehgeraetes
US3050707A (en) * 1960-12-08 1962-08-21 Judd O Baker Method and apparatus for torpedo direction locating

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468109A (en) * 1945-03-19 1949-04-26 Standard Telephones Cables Ltd Direction finder
US8179330B2 (en) * 2009-05-07 2012-05-15 Intel Corporation Omnidirectional wideband antenna

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DE633773C (de) 1936-08-05
GB393595A (en) 1933-06-06
FR703148A (fr) 1931-04-25
FR40534E (fr) 1932-07-22

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