US2606283A - Mixing circuit arrangement - Google Patents

Mixing circuit arrangement Download PDF

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Publication number
US2606283A
US2606283A US695889A US69588946A US2606283A US 2606283 A US2606283 A US 2606283A US 695889 A US695889 A US 695889A US 69588946 A US69588946 A US 69588946A US 2606283 A US2606283 A US 2606283A
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United States
Prior art keywords
wave
circuit
frequency
points
push
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US695889A
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English (en)
Inventor
Adelbert Van Weel
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Hartford National Bank and Trust Co
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Hartford National Bank and Trust Co
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    • 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
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D7/00—Transference of modulation from one carrier to another, e.g. frequency-changing
    • H03D7/14—Balanced arrangements
    • H03D7/1416—Balanced arrangements with discharge tubes having more than two electrodes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/163—Special arrangements for the reduction of the damping of resonant circuits of receivers

Definitions

  • the ob'iect of 'the present i'invention is to provide greaterfreedom in :groundingf'the junction of (the 'cathodes generally the junction oftwo corresponding input electrodes :of the dischargesystems and/or the middle of the push-pull cir-e' cuit;
  • oscillations may be-jproduced in' the circuit '.ar'-l-' rangement itself.
  • this" method is Jam-.- p'loyed,'"and the pair of 'interconnectedinputelem trodes is grounded; the circuit,'in"receivingshort waves, can be established lay-means '"of a" cavity, resonator;
  • the middle of *thepushepull circuit is grounded, the signals 'received'lbyithe antenna and having *a frequency corresponding, to the intermediate *frequencyjcannot *causema terial disturbances;
  • the network is completed first 3' fol j lowed by tuning the push-pull circuit to theirs quency i of the incoming oscillations.”
  • in-which-*the-lncoming*"osclllations are supplied through a Lecher system to the discharge systems and in which the pushpull circuit is tuned to the frequency of the incoming oscillation, such an impedance can be interposed between the input electrodes which are not connected so as to achieve optimum matching of the antenna to the discharge systems.
  • magnetically coupled inductances may be included in each half of the push-pull circuit between the antenna junctions and the discharge systems (preferably close to the said junctions).
  • FIG. 1 of the drawing represents a, mixing circuit according to my copending patent application heretofore mentioned, in which the incoming oscillations are supplied in push-pull relationship and the local oscillations in phase incidence to the control grids of two discharge systems I, I"; this mixing circuit forms part of a superheterodyne receiver for short waves.
  • the incoming oscillations received by a dipole antenna 2, 2 are fed to two conductors 3, 3 forming part of a Lecher system which, by means of a short-circuit bridge 4, is tuned to the frequency of the incoming oscillations.
  • the antenna 2, 2" is so connected to the Lecher system 3, 3" as to match the antenna correctly to the mixing tubes.
  • the Lecher system is connected to the control grids R, R" of the dischargesystems ,l', I, and the cathodes of the discharge systems are interconnected at S.
  • the middle of the short-circuit bridge 4, which is the middle of the push-pull circuit, is represented by P, the junctions of the antenna to the Lecher system being represented by Q, Q.
  • the two triodes I, I may be housed in one tube and may have a cathode in common.
  • a resonant circuit tuned to the intermediate frequency and consisting of two inductances 6, 6 and two condensers 1, 'l is connected in push-pull arrangementto the anodes of the two triodes.
  • high-frequency chokes 8", 8" which serve to prevent a transmission of the incoming high-frequency oscillations to the receiver stages next to the mixing stage.
  • the junction of coils 6 and 6 is connected to ground through a condenser 9,1Which constitutes practically a short-circuit in regard to intermediate-frequency oscillations, and, through a resistance ID to the positive terminal of a'source of anode potential (not represented).
  • coils-G'and 6" are inductively coupled with a second intermediatefrequency circuit which consists of a coil H and a condenser l2 and from which the output voltage ofthe circuit arrangement is taken.
  • the junction of the condensers I and 1 is connected to the cathodes of the two triodes so as to obtain an eleotric'circuit having a low impedance. in regard to anode currents having the oscillator frequency.
  • the middle of the push-pull circuit P is connected, to ground through a condenser l3, and the junction of the. cathodes 3 is grounded through a variablecondenser l4 and an inductanee [5 which is coupled with a coil l6 included in the output circuit of a diagrammatically rep-1 resentedlocal oscillator 0.
  • the local oscillations are fed to the input circuit of-the triode by means of so-called"cathodeinjection so that the local oscillations are set up in phase coincidence at the control-grids of the two triodes.
  • the aforesaid circuit arrangement exhibits the drawback that the input impedances of the triodes, which are represented by the capacities 5', 5", particularly in receiving ultra-short waves, have only a small value, due to which the voltage having the oscillator frequency and appearing between the control-grid and the cathode of each of the tubes usually becomes too low.
  • this circuit is constituted by the series-connection of the condensers I3, [4, the coil IS, the parallelconnected capacities 5 and 5" and the parallel connected Lecher lines 3 and 3".
  • the voltage set up across the capacities 5 and 5" and having the oscillator frequency 1. e. the voltage set up between the control grid and cathode of each triode, is a maximum in the case of series-resonance in the saidcircuit.
  • this circuit must be tuned to the oscillator-frequency.
  • the radiation of the local oscillations from the antenna 2 2" can be reduced to a minimum.
  • condensers I3 and 14 may be made variable and these elements may be adjusted in such a manner that the radiation of the local oscillations from the antenna is a minimum, whereas the voltage having the oscillator frequency and being set up between the control-grid and the cathode of each triode is a maximum.
  • Figs. 2, 3' and 4 of the drawing represent three embodiments of the invention.
  • the circuit arrangement shown in Fig. 2 substantially corresponds to that represented in Fig. 1, but the condensers l3 and M, the inductances l5 and I6 and the local oscillator O are missing. Furthermore, an inductance 22 is interposed between the junction of the cathodes S and the junction of the condensers 1 and 1''. Owing to the presence of this coil, through which flows exclusively a current having the frequency of the local oscillations, a positive feedback is obtained with respect to local oscillations. Assuming that the oscillator 0 were still available, an alternating anode voltage having the oscillator-frequency would be set up, due to the voltage loss through this coil, between the anode and cathode of each triode I and I".
  • a network by means. of whichthe single-phase. circuit can be tuned to the frequency of the local oscillations, is interposed between the points P and, S ,on-the one hand and the points Q, Q" and R'x. R'.” on theother,hand.
  • Onehalf of this network consists-oi two equal inductances 11 and l I which aremplac'edun series-connection between the points Q. and Q", a-variable condenser [8 connected between the. point P and the junction of coils l1 and H:'-, and. the parts of the Lecher system 3', 3" located between the point? and the-points .Q" andQ.” respectively. .
  • the other halfzpf the network is interposed between the points P and, S ,on-the one hand and the points Q, Q" and R'x. R'.” on theother,hand.
  • Onehalf of this network consists-oi two equal inductances 11 and l I which aremplac'edun series
  • Tiljunction of the condensers l and '7"" is preferably connectedto a tappingof this resonator.
  • the condenser may be omitted
  • rprovidin-gan impedance can be; eliminated by rprovidin-gan impedance be.-.
  • the matching of the antenna and the-tuning-of the push-pull circuit can be adjustBd again to their correct yaluesby-interposing a suitable in...
  • Fig. 3 representssa circuit arrangement acev cording to theinvention; inwhich :the input resonant ⁇ circuit is provided between the cathodes oscillations, sothat a distinct local oscillator canbe dispensed with.
  • Each anode circuit cornprises a coil 24, and 24"; moreover, owingto'the presenceof these -coi1s,. positive feedback is ob--- tained in regard to the incoming oscillations, as
  • The-.push-pull circuit consists of twc seriesconnected coils, 25': and 25 and a-tuni-ng-com denser .26.. by means of which thepush-p-ullcircuit. .can bectun-ed to-the frequencyof the incomingoscillationsr The junction]? of coils 25 and 252, which is themiddle of the push-pull circuit, is .connected directly to ground.
  • a starconnection is provided between these points and the point P, the branches of the star connection being constituted by two equal coils I1 and H and a variable condenser l8.
  • the condenser Hi By means of the condenser Hi the part of the single-phase circuit located between the point P and the points Q and Q" respectively can be tuned to the frequency of the local oscillations.
  • the part of the single-phase circuit located between ground and the points Q and Q" respectively, reckoned via the point S and the points R and R is likewise tuned to the frequency of the local oscillations by making the inductance l connected between point S and ground variable and by adjusting it to the correct value. In this way the whole single-phase circuit is brought into resonance with respect to the frequency of the local oscillations, the antenna 2, 2" being at the same time connected to a voltage node of these oscillations.
  • the cathode direct current can be supplied in a simple manner.
  • the heating current might be fed through the intermediary of double wound coils 25', 25" to the cathodes of the triodes.
  • the push-pull circuit in using ultra-short waves, is realized in the form of a Lecher-system, the heating current can be fed in a simple manner to the cathodes by making use of a Lecher system in which each conductor consists of two coaxial conductors, one of which serves in any instance for supplying and one for carrying off the heating current.
  • the coil [5 may be replaced by a star-connection similar to that used in the arrangement shown in Fig. 2 between points S and R.
  • two coils l9 and 19 are connected in series between the two cathodes R and R", the junction of these coils being connected through a condenser 29 to the points S.
  • the point S may be grounded, which yields the advantage that the source of negative grid bias can be connected directly to the point S.
  • star-connections used in Figs. 2 and 3 may be realized with two capacities and an inductance, in which the capacities are interposed between points Q and Q" and between points R and R" respectively.
  • the star-connections represented in Figs. 2 and 3 permit a much simpler adjustment.
  • the aforesaid star-connections use may also be made of the equivalent delta-connections. However, these are usually more complicated.
  • Fig. 4 represents a modification of the lefthand part of the push-pull circuit of the arrangement shown in Fig. 2. In this case, however, the point P is not directly grounded, but through a resistance 28.
  • the part of the single-phase circuit between ground and the points Q and Q respectively is not exactly tuned to the frequency of the local oscillations, so that this part behaves, for instance, as a large capacity.
  • this capacity jointly with the parallel-connected inductances of the pushpull circuit, in so far as these are located between the point P and the points Q and Q" re-
  • the left-hand part of the Lecher system may be made aperiodic by connecting it to ground through a resistance 28 having a value corresponding to the surge resistance of the parallel connected Lecher lines 3, 3" with respect to ground.
  • pair of corresponding interconnected input electrodes of the discharge systems it is not absolutely necessary for the pair of corresponding interconnected input electrodes of the discharge systems to be directly interconnected; but sometimes it may be desirable to interconnect these electrodes, for instance, through a Lecher line or a set of coils.
  • An electrical circuit arrangement for mixing a first wave and a second Wave comprising the following elements in series circuit arrangement, first and second mixing elements arranged in parallel relationship and each comprising cooperating electrodes in capacitive relationship, means to apply said first wave in phase coincidence to said mixing elements, means including a resonant impedance system having a first point constituting a substantially electrically centered tapping to apply said second wav in push-pull relationship to said mixin elements and means to tune said series circuit to the frequency of said first wave and to provide i said impedance system second and third points at a potential node for said first wave, first and second reactive elements coupled in series between said second and third points, a third reactive element coupled between said electrically centered tapping and the junction of said first and second reactive elements to tune said first and second reactive elements to the frequency of said first wave, and means to apply said second wave to said impedance system,
  • An electrical circuit arrangement for mixing a first wave and a second wave comprising the following elements in series circuit arrangement, first and second mixing elements arranged in parallel relationship and each comprising cooperating electrodes in capacitive relationship, means to apply said first wave in phase coincidence to said mixing elements, means including a resonant impedance system toned to the frequency of said second wave and having a first point constituting a substantially electrically centered tapping to apply said second wave in push-pull relationship to said mixing elements and means to tune said series circuit to the frequency of said first wave and to provide in said impedance system second and third points at a potential node for said first wave, first and second reactive elements coupled in series between said second and third points, a third reactive element coupled between said electrically centered tapping and the junction of said first and second reactive elements to tune said first and second reactive elements to the frequency of said first wave, and means to apply said second wave to said impedance system at said points of voltage node of said first wave.
  • An electrical circuit arrangement for mixing a first wave and a second wave comprising the following elements in series circuit arrangement, first and second mixing elements arranged in' parallel relationship and each comprising-cooperating 1 electrodes in capacitive relationship,
  • a Lecher system comprising first and second conductors'havingan junction of said first and second reactive ele-.
  • An electrical circuit arrangement for mixing a first wave'and a second wave comprising a pair of mixing elements each having cathode, grid and anode electrodes, said electrodes having interelectrode capacities therebetween, a Lecher system comprisingfirstand second conductors having an open end thereof coupled to said grids in push-pull relationship and having a closed end to tune said Lecher system to the frequency of-said second wave, means to interconnect said cathodes, an inductive element coupled in regenerative relationship between said cathodes and said anodes to apply said first wave tosaid cathodes in phase coincidence, a first impedance network intercoupling said control grids and said cathodes and having a variable reactive element to produce on each of said conductors a potential node for said firstwave at points intermediate to said closed end and said grids, a second impedance network intercoupling said points of potential node and said closed end and having a second variable reactive element to tune said second impedance network to the frequency of said first Wave, said Lecher
  • An electrical circuit arrangement for mixing a first wave and a second Wave comprising a pair of mixing elements each having cathode, grid and anode electrodes, said electrodes having interelectrode capacities therebetween, a Lecher system comprising first and second conductors having an open end thereof coupled to said grids in push-pull relationship and having a closed end to tune said Lecher system to the frequency of said secondlwave, means to interconnect said cathodes, a first inductive element coupled in regenerative relationship between said cathodes and said anodes to apply said first Wave to said cathodes in phase coincidence, an impedance network including said grid-cathode interelectrode capacities intercoupling said control grids and said cathodes and having a variable capacitive element to produce on each of said conductors a potential node for said first wave at points intermediate to said closed end and said grids, second and third inductive elements coupled in series between said points of potential node, a second variable capacitive element coupled between the junction of said second and
  • An electrical circuit arrangementformixing a first wave andta second wave' comprising a pair of mixing elements" each having cathode, grid andanode ele'ctrodes,'said electrodes-"having interelectrode 'capaciti'estherebetween, an riput network tuned T to "the frequency "of said second wave and coupled to said 'cathodes in push pull relationship; said input network including an-inductor having three taps, one of; said tapsecnstituting a substantially electrically' centered tapping of said input network,means -to couple said centered tapping to ground potential,- means to interconnect said grids, -a'firs'l',”reactive'- element coupled between said grids and-ground potential, said. first reactive element,- said I cathode interelectrode capacities and said input network constituting a pair of series circuits-each tuned to the frequency of said first wave,
  • ond reactive element coupled in regenerative relationship between said grids and said anodes to apply said first 'wave -to said-grids in-plia'se coincidence
  • means to produce potential nodes for the frequency ofsaid first wave' at-the-- other taps ofsaid-inductor comprising an impedance network tuned to the frequency of said first wave and intercoupling the taps on said inductor, and means to apply said second wave to said inductor.
  • An electrical circuit arrangement for mixing a first wave and a second wave comprising a pair of mixing elements each having cathode, grid and anode electrodes, said electrodes having interelectrode capacities therebetween, an input network tuned to the frequency of said second wave and coupled to said cathodes in push-pull relationship, said input network including an inductor having three taps, one of said taps constituting a substantially electrically centered tapping of said input network, means to couple said centered tapping to ground potential, means to interconnect said grids, a first inductive element coupled between said grids and ground potential, said first reactive element, said gridcathode interelectrode capacities and said input network constituting a pair of series circuits each tuned to the frequency of said first wave, a second inductive element coupled in regenerative relationship between said grids and said anodes to apply said first wave to said grids in phase coincidence, means to produce potential nodes for the frequency of said first wave at the other taps of said inductor comprising third and fourth inductive elements coupled
  • An electrical circuit arrangement for mixing a first wave and a second wave comprising the following elements in series circuit arrangement, first and second mixing elements arranged in parallel relationship and each comprising cooperating electrodes in capacitive relationship, means to apply said. first wave in phase coincidence to said mixing elements, means including a resonant impedance system having a first point constituting a substantially electrically centered tapping to apply said second wave in push-pull relationship to said mixing element, a resistive element coupled between said tapping and ground potential and means to tune said series circuit to the frequency of said first wave and to provide in said impedance system second and third points at a potential node for said first wave, first and second reactive elements coupled in series between said second and third points,
  • An electrical circuit arrangement for mixing a first wave and a second wave comprising the following elements in series circuit arrangement, first and second mixing elements arranged in parallel relationship and each comprising cooperating electrodes in capacitive relationship, means to apply said first wave in phase coincidence to said mixing elements, a Lecher system comprising first and second conductors having an open end thereof coupled to said mixing elements in push-pull relationship and having a closed end to tune said Lecher system to the frequency of said second wave, a resistive element coupled between ground potential and said closed 12 end and means to tune said series circuit to the frequency of said first wave, and to produce on each of said conductors a potential node for said first wave at points on said conductors intermediate to said closed end and said mixing elements, first and second reactive elements coupled in series between said points on said conductors, a third reactive element coupled between ground potential and the junction of said first and second reactive elements to tune said first and second reactive elements to the frequency of said first wave, and means to apply said first wave to said Lecher-system at said points of potential node.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
  • Superheterodyne Receivers (AREA)
  • Amplifiers (AREA)
US695889A 1943-03-27 1946-09-10 Mixing circuit arrangement Expired - Lifetime US2606283A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
NL248352X 1943-03-27
NL130543X 1943-05-13
NL211043X 1943-10-21
NL91143X 1943-11-09

Publications (1)

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US2606283A true US2606283A (en) 1952-08-05

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US695889A Expired - Lifetime US2606283A (en) 1943-03-27 1946-09-10 Mixing circuit arrangement
US695888A Expired - Lifetime US2609495A (en) 1943-03-27 1946-09-10 Push-pull mixing circuit arrangement
US695890A Expired - Lifetime US2606284A (en) 1943-03-27 1946-09-10 Mixing circuit arrangement

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Application Number Title Priority Date Filing Date
US695888A Expired - Lifetime US2609495A (en) 1943-03-27 1946-09-10 Push-pull mixing circuit arrangement
US695890A Expired - Lifetime US2606284A (en) 1943-03-27 1946-09-10 Mixing circuit arrangement

Country Status (5)

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US (3) US2606283A (enrdf_load_stackoverflow)
CH (1) CH248352A (enrdf_load_stackoverflow)
DE (1) DE908868C (enrdf_load_stackoverflow)
GB (1) GB632658A (enrdf_load_stackoverflow)
NL (1) NL72257C (enrdf_load_stackoverflow)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2788493A (en) * 1953-10-28 1957-04-09 Rca Corp Modulated semi-conductor oscillator circuit

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2710315A (en) * 1950-11-03 1955-06-07 Ben H Tongue Wide-band amplifying system
US2802069A (en) * 1954-09-07 1957-08-06 Bell Telephone Labor Inc Amplifier with high frequency compensation
US2857511A (en) * 1956-03-02 1958-10-21 Ben H Tongue Balanced mixer
US3110863A (en) * 1959-09-21 1963-11-12 Vector Mfg Company Phase modulation transmitter
US3275951A (en) * 1963-08-01 1966-09-27 Joachim A Maass Ring modulator with large dynamic operating range

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1396786A (en) * 1916-11-06 1921-11-15 Western Electric Co System for transmission of intelligence
US1596102A (en) * 1924-12-24 1926-08-17 American Telephone & Telegraph High-frequency translating circuits
US1767508A (en) * 1925-07-27 1930-06-24 Crosley Radio Corp Vacuum-tube circuits
US1968610A (en) * 1931-03-23 1934-07-31 Rca Corp Thermionic amplifying system
US2088432A (en) * 1934-02-17 1937-07-27 Rca Corp Frequency converter circuit
US2107395A (en) * 1933-12-13 1938-02-08 Schlesinger Kurt Radio receiving system
US2434474A (en) * 1941-01-28 1948-01-13 Hartford Nat Bank & Trust Co Circuit arrangement for ultra short waves
US2441452A (en) * 1941-01-31 1948-05-11 Hartford Nat Bank & Trust Co Frequency changing circuits
US2453078A (en) * 1940-12-05 1948-11-02 Hartford Nat Bank & Trust Co Device for wave length transformation of very short waves
US2479537A (en) * 1942-12-30 1949-08-16 Gen Electric Detector-oscillator circuit for ultra high frequency receivers

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR690565A (fr) * 1930-05-13 1930-09-23 Radio Electr Soc Fr Perfectionnements aux récepteurs de télégraphie et téléphonie sans fil
US2169305A (en) * 1935-06-15 1939-08-15 Rca Corp Low-loss circuits
DE727990C (de) * 1939-10-06 1942-11-17 Habil Friedrich Vilbig Dr Ing Verfahren zur Beseitigung der durch Amplituden- und/oder Phasenverzerrung der beidenSeitenbaender hervorgerufenen Stoerungen einer mit Traegerfrequenz uebertragenen Nachricht
BE470453A (enrdf_load_stackoverflow) * 1942-11-16
US2483766A (en) * 1942-12-29 1949-10-04 Rca Corp Power converter system

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1396786A (en) * 1916-11-06 1921-11-15 Western Electric Co System for transmission of intelligence
US1596102A (en) * 1924-12-24 1926-08-17 American Telephone & Telegraph High-frequency translating circuits
US1767508A (en) * 1925-07-27 1930-06-24 Crosley Radio Corp Vacuum-tube circuits
US1968610A (en) * 1931-03-23 1934-07-31 Rca Corp Thermionic amplifying system
US2107395A (en) * 1933-12-13 1938-02-08 Schlesinger Kurt Radio receiving system
US2088432A (en) * 1934-02-17 1937-07-27 Rca Corp Frequency converter circuit
US2453078A (en) * 1940-12-05 1948-11-02 Hartford Nat Bank & Trust Co Device for wave length transformation of very short waves
US2434474A (en) * 1941-01-28 1948-01-13 Hartford Nat Bank & Trust Co Circuit arrangement for ultra short waves
US2441452A (en) * 1941-01-31 1948-05-11 Hartford Nat Bank & Trust Co Frequency changing circuits
US2479537A (en) * 1942-12-30 1949-08-16 Gen Electric Detector-oscillator circuit for ultra high frequency receivers

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2788493A (en) * 1953-10-28 1957-04-09 Rca Corp Modulated semi-conductor oscillator circuit

Also Published As

Publication number Publication date
NL72257C (enrdf_load_stackoverflow)
US2609495A (en) 1952-09-02
CH248352A (de) 1947-04-30
US2606284A (en) 1952-08-05
GB632658A (en) 1949-11-28
DE908868C (de) 1954-04-12

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