US2274486A - Piezoelectric resonator circuit - Google Patents

Piezoelectric resonator circuit Download PDF

Info

Publication number
US2274486A
US2274486A US335963A US33596340A US2274486A US 2274486 A US2274486 A US 2274486A US 335963 A US335963 A US 335963A US 33596340 A US33596340 A US 33596340A US 2274486 A US2274486 A US 2274486A
Authority
US
United States
Prior art keywords
circuit
crystal
frequency
electrodes
electrode
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
US335963A
Other languages
English (en)
Inventor
Winfield R Koch
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.)
RCA Corp
Original Assignee
RCA 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
Priority to NL61184D priority Critical patent/NL61184C/xx
Application filed by RCA Corp filed Critical RCA Corp
Priority to US335963A priority patent/US2274486A/en
Priority to GB6427/41A priority patent/GB546319A/en
Application granted granted Critical
Publication of US2274486A publication Critical patent/US2274486A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
    • H03H9/545—Filters comprising resonators of piezoelectric or electrostrictive material including active elements
    • 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
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/30—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator
    • H03B5/32—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator being a piezoelectric resonator
    • H03B5/34—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator being a piezoelectric resonator active element in amplifier being vacuum tube
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C1/00—Amplitude modulation
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C3/00—Angle modulation
    • H03C3/10—Angle modulation by means of variable impedance
    • H03C3/12—Angle modulation by means of variable impedance by means of a variable reactive element
    • H03C3/14—Angle modulation by means of variable impedance by means of a variable reactive element simulated by circuit comprising active element with at least three electrodes, e.g. reactance-tube circuit

Definitions

  • This invention relates to piezo-electric resonator circuits adaptedgenerally for filtering, oscillation generation, and frequency modulation.
  • the coating on the crystal surface or the electrode area of a crystal element in a signal conveying circuit is divided, and a segregated area or certain segregated areas are connected to a suitable reactance or resistance network included in a separate control circuit by which the frequency and ,damping of the signal conveying circuit through the crystal or piezo-electric resonator is controlled, the control circuit being coupled with the signal channel only through the crystal element of the resonator circuit.
  • Figure 1 is a schematic circuit diagram of a piezo-electric resonator circuit embodying the invention.
  • Figure 2 is a further schematic circuit diagram of a modification of the circuit of Fig. 1, also embodying the invention and adapted for frequency modulation.
  • a portion of a high frequency signal transmission circuit comprising input terminals 5 and output terminals 6 between, which are connected two amplifier stages in cascade, comprising amplifier ⁇ tubes land8.
  • the first stage amplifier- 1' comprises an input grid circuit 5 having an input impedance l0 connected. across the terminalsj, and an output anode circuit ,l I which; includes the tuned primarywinding l2of ahigh frequency-interstage coup i strans rmen. 1 .T a seqqn em t itthe' ran o m s.
  • the tuned circuits shown may be tuned to the crystal frequency, in which case the circuit operates to convey signals at that frequency, amplifled in thestages I and 8, from the input terminals 5 to the output terminals 6.
  • the crystal circuit is provided with a grounded center tap -20 on the secondary l4 and a circuit from one terminal of the secondary to an input electrode 2
  • An output electrode 23 is connected to the high side of the input circuit l6 and through a neutralizing capacitor 24 to the opposite terminal of the secondary. Signals are conveyed through the circuit between the ground connection 20 and the high side of the circuit, thence through the crystal to the imput circuit IS.
  • the crystal capacity is neutralized by proper adjustment of the capacitor 24.
  • the crystal may be of any suitable material, such as Rochelle salt or quartz.
  • and 23, is provided for signal control purposes, in accordance with the invention, with auxiliary control electrodes.
  • auxiliary control electrodes In the present example, two such separate electrodal areas are indicated at 26 and 21 at the opposite end of the crystal from the electrodes 2
  • the control or auxiliary electrodes are connected with a control circuit 28 which includes a predetermined resistance or reactance 29, together with a tuned circuit 30 in shunt therewith and effective to tune out the inherent shunting capacity of the electrodes 26 and 21 across the impedance or reactance device 29.
  • the reactance device is preferably a resistor, as shown, having no appreciable frequency characteristic and the circuit 30 preferably includes a tuning inductance 3
  • the frequency and damping of the resonator circuit l5 may be changed without change in the associat'ed input and output circuits. as commonly required, and without changing the dimensions of the resonator circuit electrodes.
  • a resistance device such as that shown at 29 may be made to match that of the segregated area between the electrodes '26 and 21 so that the resistance device will absorb power sufflcient to reduce effectively the selectivity afforded by the areas 2
  • the control circuit may be operated at low potential to ground.
  • one of the electrodes 21 may be connected to ground along with the low potential side of the impedance 29 and the tuned circuit 30, as indicated at 35.
  • the electrodes 26 and 21 and the control circuit have no appreciable undesired effects upon the signal selecting portion of the system, such as the crystal resonator circuit 15.
  • the impedance of the element 29 is preferably higher than the effective impedance of the parallel resonant circuit 30 and may be of the order of several thousand ohms, or may be increased above that value with regeneration applied thereto.
  • variation of the impedance 29 causes the impedance of the crystal in the signal conveying resonator circuit I5 to vary, thereby causing the signal transmission or gain through the circuit to vary, together with the selectivity of the circuit I5.
  • the interstage coupling system is a modification of the piezo-electric resonator circuit of Fi 1 in which the crystal is indicated at 40 having on one face thereof a grounded electrode or coating 4
  • the input electrode 42 is coupled through a capacitor 45 with the output circuit ll of the first stage 1 across a suitable anode impedance, preferably an anode re sistor 46 having no appreciable frequency char- 5 acteristic.
  • the output electrode 44 is connected with the input circuit [6 of the output stage 8' across a grid resistor 41.
  • control circuit in the present example is connected between the segregated electrodal area provided at 43, preferably intermediate between the electrodes 42 and 44,
  • the control circuit includes a lead 50 connected between the electrode 43 and a coupling erably of relative low impedance or reactance at the resonant frequency or circuit 53.
  • variation of the tuning of the control circuit 53 from resonance is effective to cause a shift in the resonant frequency of the crystal 4B and this may be controlled by any suitable means.
  • the variation in frequency may be made in accordance with an audio modulation frequency by connecting a variable reactance tube 60 with the circuit 53, as shown, the plate 6
  • the tube 60 is of the screen grid pentode type having a cathode 65 connected to ground through a suitable bias resistor 66 provided with a bypass capacitor 61.
  • a variable bias is derived from the resistor 66 through a tap connection 68 connected back to the control grid 53 through an input circuit comprising a transformer secondary 69 and a grid resistor 10.
  • the loading of the tube 60 may be controlled and adjusted to such a value that the circuit 53 is in resonance with the crystal frequency, or the adjustment may provide for shifting the resonant frequency of the crystal as desired.
  • the resonant frequency of the circuit 53 may then be further shifted to vary the resonant frequency of the crystal circuit by applying modulation signals to the grid 63 through the transformer 69 from any suitable source such as a microphone H.
  • oscillations representing the mean frequency or carrier are transmitted throu'ghthe crystal circuit, for example, by connecting the high potential output terminal 6 through a feedback circuit 70 13 to a feedback input terminal 14 which is connected to the high potential side of the input circuit 5. thereby causing the system to oscillate at the crystal frequency.
  • the strength of'oscillations is determined by a series controlling resistor 16 in the feedback circuit. and the output-anode circuit. I8 is decoupled for. direct currents, from the input circuit, .by a capacitor I1 also in the lead 13..
  • the input electrode 43 and the output electrode 44 are shielded from the control electrode 43 on the crystal by shield plates 18 interposed between the electrodes and connected to ground 80. This effectively prevents any interaction between-electrodes except through the crystal.
  • a piezo-electric resonator in a signal-conthe piezo-electric resonator may be varied on either side of the resonance by means of suitable impedance crreactance devices in the auxiliary control circuit, and auxiliary electrode means associated with the piezo-electric device in the resonator circuit associated with areas of the said device not associated withthe main electrodes.
  • the piezo-electric device in the resonator circuit is provided with signal input and output electrodes and an auxiliary electrode preferably shielded from the input and output electrodes and connected with the isolated control circuit containing the tuning or impedance varying device or circuit network.
  • Amplitude and phase modulation results from detuning the control circuit from the crystal frequency and varying the impedance of the circuit, whereas amplitude control alone is provided when the control circuit is tuned to th crystal frequency.
  • Frequency modulation of oscillations transmitted through the crystal or piezo-electric device may be provided in the same manner through the use of the auxiliary electrode connection with the crystal and the auxiliary control circuit containing a variable reactance device responsive to the modulation signals. It is apparent that the reactance device 60 may be replaced by any I and means for adjusting the resistive component of said impedance to a value of the order of the value of the resistive component of the crystal 7 impedance.
  • a piezo-electric crystal-controlled oscillation-generating circuit oscillation control means including a piezo-electric crystal and a pair of signal conveying electrodes therefor, circuit means connected with said electrodes for conveying signals through said crystal as a circuit coupling element, a third electrode for said crystal in spaced relation to said first-named electrodes, and a variable reactance circuit connected with said third electrode for. varying the resonant frequency of the crystal.
  • a piezo-electric crystal-controlled oscillation-generating circuit including a piezo-electric crystal and a pair of signal conveying electrodes therefor, circuit means connected with said electrodes for conveying signals through said crystal as a circuit coupling element, a third electrode for said crystal in spaced relation to said first named electrodes, a variable reactance circuit connected with said third electrode for varying the resonant frequency of the crystal, and means providing a shield between said third electrode and said first named electrodes.
  • a piezo-electric resonator circuit comprising a piezo-electric crystal for determining the frequency of signals transmitted therethrough, means providing a signal input and a signal output electrode for said crystal, signalconveying circuits coupled to said input and output electrodes responsive to signals at a frequency of the order of the crystal frequency, means providing an auxiliary electrode associated with said crystal, and means providing a reactance in circuit with said auxiliary electrode for determining the frequency of oscillation of said crystal between predetermined limits.
  • a piezo-electric resonator circuit comprising a piezq-electric crystal for determining the frequency of signals transmitted therethrough, means providing a signal input and a signal output electrode for said crystal, signal conveying circuits coupled to said input and output electrodes responsive to signals ataa frequency of the order of the crystal frequency, means providing an auxiliary electrode associated with said crystal, means providing reactance in circuit with said auxiliary electrode for determining the frequency of oscillation of said crystal between pre-- nected with said electrodes for conveying oscillations through said crystal device as a circuit coupling element, an auxiliary control electrode associated with said crystal device, an auxiliary control circuit connected with said lastdnamed electrode, variable impedance meansiiii' said circuit, and means in shunt therewith for neutralizing the capacity of said electrode.
  • a piezo-electric crystal-controlled signalconveying system having a piezo-electric crystal provided with signal input and output electrodes, signal-conveying circuits connected with said electrodes, circuit means connected with said electrodes for conveying signals through said crystal as a circuit coupling element, an auxiliary electrode associated with said crystal in spaced relation to'said first-named electrodes, a tuned circuit connected with said last-named electrode, and means for varying the reactance of said circuit thereby to vary the signal transmission characteristic of said crystal.
  • a piezo-electric resonator circuit comprising, in combination, a piezo-electric crystal device having an input electrode and an output electrode, means connected with said electrodes for conveying electrical oscillations through said crystal at a frequency of the order of the crystal frequency, an auxiliary electrode for said crystal, a variable reactance circuit connected with said electrode, and means responsive to sound frequencies for varying 'the reactance of said lastnamed circuit.
  • the combination with a signal amplifier, of an interstage coupling network comprising, in combination, a piezo-electric crystal having an input electrode and an output electrode, circuit means connected with said electrodes for conveying signals through said crystal as a circuit coupling element, a pair of additional electrodes associated with a predetermined area of said crystal in spaced relation to said first-named electrodes, a control circuit connected between said last-named electrodes, and means providing a variable impedance in said control circuit tor .varying the transmission characteristic of said first-named circuit means.
  • a high frequency signal-conveying system comprising, in combination, a piezo-electric crystal having an input electrode and an output electrode,,circuit means connected---with said electrodes for conveying signals through said crystal as a circuit coupling element, a pair of additional electrodes associated with a predetermined area of said crystal in spaced relation to said first-named electrodes, a control circuit connected between said lastnamed electrodes, means providing a variable impedance in said control circuit for varying the transmission characteristic of said first-named circuit, one of said last-named electrodes being grounded, and means providing a grounded screen between at least one of said auxiliary electrodes and said first-named electrodes.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
US335963A 1940-05-18 1940-05-18 Piezoelectric resonator circuit Expired - Lifetime US2274486A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
NL61184D NL61184C (en, 2012) 1940-05-18
US335963A US2274486A (en) 1940-05-18 1940-05-18 Piezoelectric resonator circuit
GB6427/41A GB546319A (en) 1940-05-18 1941-05-19 Improvements in piezo-electric circuits

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US335963A US2274486A (en) 1940-05-18 1940-05-18 Piezoelectric resonator circuit

Publications (1)

Publication Number Publication Date
US2274486A true US2274486A (en) 1942-02-24

Family

ID=23313988

Family Applications (1)

Application Number Title Priority Date Filing Date
US335963A Expired - Lifetime US2274486A (en) 1940-05-18 1940-05-18 Piezoelectric resonator circuit

Country Status (3)

Country Link
US (1) US2274486A (en, 2012)
GB (1) GB546319A (en, 2012)
NL (1) NL61184C (en, 2012)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2424246A (en) * 1943-09-16 1947-07-22 Bell Telephone Labor Inc Frequency-modulated crystal oscillator
US2539268A (en) * 1945-04-25 1951-01-23 Motorola Inc Oscillator
US2577297A (en) * 1944-01-22 1951-12-04 Antranikian Haig Signaling system
US2872577A (en) * 1956-08-13 1959-02-03 Robert W Hart High frequency integrating signal detector
US2881390A (en) * 1952-04-21 1959-04-07 Gen Electric Piezo-electric type frequency changer
US2920276A (en) * 1953-03-04 1960-01-05 Philips Corp Device for modulating and/or amplifying electric signals

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2424246A (en) * 1943-09-16 1947-07-22 Bell Telephone Labor Inc Frequency-modulated crystal oscillator
US2577297A (en) * 1944-01-22 1951-12-04 Antranikian Haig Signaling system
US2539268A (en) * 1945-04-25 1951-01-23 Motorola Inc Oscillator
US2881390A (en) * 1952-04-21 1959-04-07 Gen Electric Piezo-electric type frequency changer
US2920276A (en) * 1953-03-04 1960-01-05 Philips Corp Device for modulating and/or amplifying electric signals
US2872577A (en) * 1956-08-13 1959-02-03 Robert W Hart High frequency integrating signal detector

Also Published As

Publication number Publication date
NL61184C (en, 2012)
GB546319A (en) 1942-07-07

Similar Documents

Publication Publication Date Title
US2173427A (en) Electric oscillator
US2269417A (en) Cathode-driven oscillator
US2323598A (en) Variable signal response network
US2925561A (en) Crystal oscillator system
US2749441A (en) Phase shift oscillator
US2274486A (en) Piezoelectric resonator circuit
US2438392A (en) Oscillation generation control
US2267453A (en) Automatic frequency control circuits
US2598722A (en) Frequency modulation system
US2458760A (en) Crystal controlled frequency modulation system
US2383848A (en) Reactance control circuit
US2662171A (en) Superheterodyne receiving arrangement for use at ultrashort waves
US2459557A (en) Wave length modulation
US2054757A (en) Piezoelectric filter
US2165468A (en) High-frequency oscillator
US2509280A (en) Cathode-driven oscillator
US2256067A (en) Receiver selectivity control
US2774943A (en) Frequency modulated oscillator
US2730577A (en) Frequency selective amplifier circuit
US2925562A (en) Frequency modulated crystal oscillator circuit
US3271693A (en) Band rejection filter
US2093094A (en) Radio frequency amplifier
US2691106A (en) Variable reactance electron tube circuit
US2044137A (en) Crystal controlled oscillator circuits
US2489327A (en) Crystal controlled oscillator