JPS60165815A - Tuner - Google Patents

Abstract

PURPOSE:To save materials and to install remotely constituted inductors respectively by providing a tuning inductor, a control inductor connected to said tuning inductor and a transmission line having a length nearly equal to an odd number multiple of a lambda/4 electric length in the tuning frequency and inserted and connected between the tuning inductor and the control inductor. CONSTITUTION:A reactance element is connected to the inductor via the transmission line having a length nearly equal to an odd number multiple of a lambda/4 electric length in the tuning frequency. The impedance converting function with the combination of the transmission line and the reactance element connected thereto is realized and the converted reactance having a property opposite to that of the reactance of the reactance element to be converted realized in this way is acted onto the inductor equivalently in parallel or series. For example, an impedance converter 18 comprising an inductor 17 to be converted connected to the tuning inductor 15 via a coaxial cable of a lambda/4 electric length is connected and installed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a tuner that can be used in radio and television receivers and transmitters 5 and other communication devices in general.

Conventional configurations and their problems In recent years, the number of broadcast waves for radio and television or communication waves for communication devices has been increasing, and the performance of tuners that select the frequency of signals to be received or transmitted has been increasing. Stability and reliability are increasingly required. On the other hand, reducing manufacturing costs, including frequency adjustment, in receivers, transmitters, and communication devices in which tuners are installed is also an important issue. Technology development is needed.

A conventional tuner will be described below with reference to the drawings. Figure 1 shows a basic tuning circuit, where 1 is an inductor,
2 is a capacitor. A tuner constituted by a parallel resonant circuit 3 consisting of an inductor 1 and a capacitor 2 has conventionally been realized with a configuration of components as shown in FIG. 2. As a method as shown in FIG. 2, a planar inductor 9 is installed on the surface of a plate-shaped dielectric 8, and a capacitor 12 consisting of opposing electrodes 10 and 11 is installed, respectively, to form separate inductors. 9 and capacitor 12 were connected by circuit conductors 13 and 14 to form a tuner.

However, in the above configuration, a capacitor component is always required, and the area occupied by the capacitor is large, which hinders the realization of miniaturization of the device. Furthermore, at least three functional electrodes, an inductor electrode and a counter electrode forming a capacitor, are required to function to constitute each component, and electrode materials with high conductivity and therefore high costs are required. Since a large quantity is used, the manufacturing cost of the tuner becomes high, and at the same time, it is impossible to save materials. As a result, there are problems in that there is a limit to the cost reduction of the tuner.

Purpose of the Invention An object of the present invention is to provide a tuner that can be constructed using only inductors as reactance components without using capacitors, and in which each of the constituent inductors can be installed remotely. That is.

Structure of the Invention In order to achieve the above object, the present invention has a structure in which a reactance element is connected to an inductor via a transmission line having a length approximately equal to an odd multiple of λ/4 electrical length at a tuning frequency. As a result, a combination of a transmission line having a length equal to an odd multiple of λ/4 electrical length and a reactance element connected thereto exhibits an impedance conversion function, and the reactance of the converted reactance element realized thereby The converted reactance having the opposite properties is applied isometrically to the implant in parallel or in series.

DESCRIPTION OF EMBODIMENTS Tuners in embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows a circuit diagram of a tuner in a first embodiment of the invention. In the figure, 15 is a tuning inductor, and a coaxial cable 1 of λ/4 electrical length is connected to it.
An impedance converter 18 to which an inductor 17 to be converted is connected via an inductor 6 is connected and installed.

FIG. 4 shows a circuit diagram of a tuner in a second embodiment of the invention. In the figure, 19 is a tuning inductor, and a coaxial cable 2 of λ/4 electrical length is connected to it.
An impedance converter 22 to which a variable inductor 21 to be converted is connected via 0 is connected and installed.

FIG. 5 shows a circuit diagram of a tuner in a third embodiment of the invention. In the figure, 23 is a tuning inductor, and a coaxial cable 2 of λ/4 electrical length is connected to it.
An impedance converter 26 to which a variable current inductor 25 to be converted is connected via 4 is connected and installed.

FIG. 6 shows a circuit diagram of a tuner in a fourth embodiment of the invention. In the figure, 27 is a variable tuning inductor, and an impedance converter 30 is connected thereto to which an inductor 29 to be converted is connected via a coaxial cable 28 having an electrical length of λ/4.

FIG. 7 shows a circuit diagram of a tuner in a fifth embodiment of the invention. In the figure, 3I is a tuned current variable inductor, to which is connected an impedance converter 34 to which an inductor 33 to be converted is connected via a coaxial cable 32 having an electrical length of λ/4.

FIG. 8 shows a circuit diagram of a tuner in a sixth embodiment of the invention. In the figure, 35 is a tuning inductor, and an inductor 40 to be converted is connected to it through a transmission line 39 having a λ/4 electrical length and consisting of electrodes 37 and 38 placed opposite each other with a dielectric 36 interposed therebetween. An impedance converter 41 is connected and installed.

FIG. 9 shows a circuit diagram of a tuner in a seventh embodiment of the invention. In the figure, 42 is a tuning inductor, to which a variable inductor 47 to be converted is connected via a transmission line 46 of λ/4 electrical length consisting of electrodes 44 and 45 placed opposite to each other with a dielectric 43 in between. An impedance converter 48 is connected and installed.

FIG. 10 shows a circuit diagram of a tuner in an eighth embodiment of the invention. In the figure, 49 is a tuning inductor, to which a variable current inductor 54 to be converted is connected via a transmission line 53 of λ/4 electrical length consisting of electrodes 51 and 52 placed opposite to each other with a dielectric 50 in between. An impedance converter 55 is connected and installed.

FIG. 11 shows a circuit diagram of a tuner according to a ninth embodiment of the present invention. In the figure, 56 is a tuned variable inductor, to which an inductor 61 to be converted is connected via a transmission line 60 of λ/4 electrical length consisting of electrodes 58 and 59 placed opposite to each other with a dielectric 57 in between. An impedance converter 62 is connected and installed.

FIG. 12 shows a circuit diagram of a tuner in a tenth embodiment of the present invention. In the figure, 63 is a tuned current variable inductor, and an inductor 68 to be converted is connected to it via a transmission line 67 having a λ/4 electrical length and consisting of electrodes 65 and 66 placed opposite each other with a dielectric 64 in between. An impedance converter 69 is connected and installed.

In each of the above embodiments, the transmission line of λ/4 electrical length can be easily constructed using a general coaxial cable in the embodiments shown in FIGS. 3 to 7, and the printing method is used in the embodiments shown in FIGS. A thin transmission line with an electrical length of λ/4 can be easily constructed.

In addition, the ones shown in Figs. 3 and 8 can be configured as a tuner with a fixed tuning frequency, and the ones shown in Figs. 4, 6, 9, and 11 can be configured as a tuner with a variable tuning frequency. 5, FIG. 7, FIG. 10, and FIG. 12 can constitute a tuner with a current variable tuning frequency.

Furthermore, in each of the nine embodiments described above, the electrical length of the transmission line in the impedance converter is λ/4. It is also possible to construct a similar tuner using

In each of the embodiments shown in FIGS. 8 to 12, a transmission line in which a pair of electrodes are disposed opposite to each other with a dielectric interposed therebetween is used, but the respective electrodes are arranged side by side on the same surface of the dielectric. It is possible to construct a similar tuner even if the two electrodes are disposed opposite each other inside a dielectric material.

Furthermore, in the embodiments shown in FIGS. 3 to 12, parallel resonant tuners are shown, but series, π-type, L-type, and reverse-type resonant tuners can also be configured in the same way. Is possible.

Furthermore, in each of the embodiments shown in FIGS. 3 to 12, the L length of the transmission line used does not strictly require λ/4 electrical length, but a transmission line with approximately the same length is used. It is possible to configure

In addition, as the transmission line electrode in each of the embodiments shown in FIGS. 8 to 12 above, metal conductors, printed metal foil conductors, thick film printed conductors, thin film conductors, etc. can be used.
Moreover, different types of the above-mentioned conductors may be combined. on the other hand,
Dielectric materials include alumina ceramic, barium titanate, plastic, polyfluoroethylene fiber, glass,
Mica.

Resin-based printed circuit boards can be used.

The operations of the tuners of these embodiments configured as described above will be explained below.

FIGS. 13(a) and 13(b) are equivalent circuits and Smith diagrams for explaining the operation of the λ/4 electrical length impedance converter in the tuner of the present invention. Figure 13 fat
In a transmission line with an electrical length β and a load Z (A) connected to the tip as shown in , the normalized input impedance and normalized input admittance when looking at the load side from Z = 0 are as follows: In the case of no loss (γ−jβ), it can be expressed as.

Here, if l = λ/4, then ββ-(2π/λ) (λ/4) = π/2...(3), so tan β1=tanπ/2=■...・(4)
becomes.

On the other hand, if the electrical length β of the line is an odd multiple of λ/4, then β1=(2π/λ)(λ/4)・n (n=1.3, 5, 7.-)...( 5) tan β
II 1 = tan π/ 2 =” (when n=1)
・・・・・・・・・(6)jan βm! 3=tan3π
/2=-■ (when n=3)...(7)t
an βj! 6=tan5π/2=■ (in case of n-5)
......(8), and in either case, the normalized input impedance and input admittance shown in equations (1) and (2) are Zo Z (β) Y.

becomes.

That is, the normalized input impedance seen from a certain reference plane on the load side is equal to the normalized input admittance seen from the reference plane separated by an electrical length λ/4 from that point.

Further, the normalized input admittance seen from a certain reference plane on the load side is equal to the normalized input impedance seen from the reference plane separated by an electrical length λ/4 from that point on the load side. This provides an impedance conversion function.

The mode in which the operation of the impedance converter described above affects the operation of the tuner according to the embodiment of the present invention will be described below. The inductor to be converted installed in the impedance converter in each embodiment is located at position 70 representing inductive reactance in the Smith diagram shown in FIG. 13(b), and as a result of impedance conversion, represents capacitive reactance. 71 position. In addition, when the value of the inductor to be converted is changed, that is, by increasing the inductance to be converted and moving the inductive reactance 72 upward, the capacitive reactance 73 whose impedance is converted is moved to decrease and the capacitance is increased. On the contrary, by decreasing the transformed inductance and moving the inductive reactance 74 downward, it is possible to move the impedance transformed capacitive reactance 75 upward and decreasing the capacitance.

Due to the operation of the tuner according to the embodiment of the present invention described above, the tuner according to the embodiment shown in FIGS. 3 to 12 can be represented by an equivalent circuit shown in FIG. 14 (.). That is, the converted equivalent capacitance 78 in the impedance converter 77 is connected in parallel to the tuning inductor 76, thereby making it possible to configure a parallel resonant circuit. On the other hand, the first
It is also possible to configure a series resonant circuit by connecting the converted equivalent capacitance 81 of the impedance converter 80 in series with the tuning inductor 79 as shown in FIG. 4(b).

Further, as a modification of the equivalent circuit shown in FIG. 14(a), (bl), it is also possible to configure a π-type, L-type, or inverted-type resonant circuit.

Effects of the Invention As described above, the present invention has a configuration in which a reactance element is connected to an inductor via a transmission line having a length approximately equal to an odd multiple of λ/4 electrical length at a tuning frequency. , an equivalent reactance having opposite properties to the reactance of the reactance element is connected in parallel or series with the inductor,
A tuner is realized by configuring a parallel resonant circuit or a series resonant circuit isometrically.

This provides an excellent effect in that a tuner can be configured simply by using an inductor as a reactance component. This also eliminates the need for a capacitor in the tuner, which eliminates the problems that existed in conventional tuners that use capacitors, especially tuners that use planar capacitors with laminated electrodes, that is, they are large in size. It is possible to eliminate the increase in the amount of unnecessary radiation of the tuning signal due to the capacitor electrode area and the large fluctuation in the tuning frequency and tuning Q when another conductor is close to the tuner due to the same cause. You can get the invasive effect of being able to do it. As a result, it is possible to construct a tuner that is small and compact, has an extremely small amount of unnecessary radiation of the tuning signal, is less affected by nearby conductors in the surroundings, and is extremely stable. An excellent effect can be obtained in that the tuning performance of a communication device such as a receiver or a transmitter in which this tuner is installed can be dramatically improved.

Furthermore, even if each tuning component in the tuner is installed remotely, the impedance of the λ/4 transmission line can be stably ensured, so it is possible to determine the stray capacitor and lead inductance. It is possible to realize a tuned RLI device with extremely high tuning frequency accuracy even if each tuning component in the ζ harmonizer is installed remotely, and by varying any of the tuning components installed remotely. An excellent effect is obtained in that the tuning frequency can be remotely controlled.

[Brief explanation of drawings]

FIG. 1 is a basic circuit diagram of a tuner, FIG. 2 is a perspective view showing the configuration of a conventional tuner, FIGS. 3 to 12 are circuit diagrams of a tuner according to an embodiment of the present invention, and FIG. 13
FIGS. 14(a) and 14(b) are explanatory diagrams showing the operating principle of the tuner of the present invention, and FIG. 14(a). (bl is an equivalent circuit diagram of a tuner in an embodiment of this invention. 15, 19.23, 35.42.49... Tuning inductor, 27.56... Tunable variable inductor, 31°63...・Tuned current variable inductor, 16. 20.2
4゜28.32...λ/4 coaxial cable, 37.3B
. 44.45, 51.52.5B, 59.65.6G. ...λ/4 transmission line electrode, 36, 43.50, 57°6
4...dielectric, 39,46,53.60.67...
λ/4 transmission line, 17, 29, 33, 40, 61°68・
... Converted inductor, 21.47... Converted variable inductor, 25.54. ...Converted current variable inductor, 18.22, 26, 30.34, 41°48.55
．． 62.69...λ/4 impedance converter Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 61A Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Figure 14

Claims (8)

[Claims] (1) A tuning inductor, a control inductor connected to this tuning inductor, and approximately λ/4 at the tuning frequency.
A tuner comprising a transmission line having a length equal to an odd multiple of an electrical length and interposed and connected between the tuning inductor and the control inductor. (2) The tuner according to claim (1), which uses a variable inductor as the control inductor. (3) The tuner according to claim (1), which uses a variable current inductor as the control inductor. (4) Claim No. 1 in which the transmission line is a coaxial cable (
Tuner described in section 1). (5) The tuner according to claim (1), wherein the transmission path is constituted by a pair of electrodes with a dielectric interposed therebetween. (6) The tuner according to claim (1), which uses a variable inductor as the tuning inductor. (7) A tuner according to claim 11, which uses a current variable inductor as the tuning inductor. (8) The tuning inductor, control inductor, and transmission line constitute any of parallel, series, π-type, L-type, and reverse-type resonant circuits, or any combination of these resonant circuits. A tuner according to claim (1).