JPH03750Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention mainly relates to a distributed constant delay line used in color television receivers. Color television receivers are generally configured to incorporate a delay line into the video amplification circuit after the video detection circuit to match the delay of the color signal. The amount generated must be adjusted. Furthermore, there is a close relationship between the delay line preshoot amount and the phase characteristic, that is, the group delay time characteristic, and the closer the group delay time is to a flat value with respect to the frequency, the smaller the preshoot amount becomes. The present invention utilizes the above relationship to provide an improved distributed constant delay line that can improve the phase characteristics mainly to reduce the amount of preshoot. In general, a distributed constant delay line constructed within the same bobbin can be considered to be a combination of several or more than ten lattice circuits as shown in Figure 1, considering the bridging stray capacitance attached to the inductance between adjacent winding grooves. Therefore, the group delay time tends to decrease as the frequency increases, as shown in FIG. 2, and the degree of decrease varies depending on the coupling coefficient K. In Figure 1, L ₀ is the inductance of the signal winding wound in each winding groove, 2C ₀ is the capacitance between the signal winding and the ground electrode winding in each winding groove, and C ₀ /2 is the adjacent Stray capacitance between signal windings,
K indicates the coupling coefficient between adjacent signal windings. Note that the coupling coefficient K is expressed as K=m ² −1/m ² +1, where m is the coefficient of the m-type induction between the signal windings. Therefore, the coupling coefficient K changes by changing the induction m-type coefficient m, and the group delay time changes as shown in Figure 2 by changing the induction m-type coefficient m. Become. Therefore, the coupling coefficient K can generally be changed by changing the bobbin core diameter and the winding groove spacing, that is, the width of the brim of the bobbin, but with this method, the bobbin shape can be changed depending on the pre-cut amount. However, there were problems with the management of the bobbin during mass production, and it was also disadvantageous in terms of cost. Therefore, the present invention eliminates the above-mentioned drawbacks and provides a distributed constant type delay line in which the signal winding is wound on the same bobbin, thereby performing phase compensation and reducing the amount of preshoot. . Embodiments of the present invention are shown below in drawings 3 to 5.
This will be explained using figures. FIG. 3 is a cross-sectional view of one embodiment of the distributed constant type delay line of the present invention, in which a conductor coated with an insulating film is connected to an insulating bobbin 1 having a plurality of winding grooves 2 and 3 using a plurality of collars 4. The earth electrode windings 6 and 7 are formed by continuously winding the winding grooves 2 and 3, and the conductor wire is provided with an insulating film in between, and the number of turns is alternately varied between adjacent winding grooves. The parallel signal windings 5 and 5' are continuously wound to form a distributed constant delay line. Note that 8 and 9 are the terminals of the signal windings 5 and 5',
Reference numeral 10 denotes terminals of the ground electrode windings 6 and 7, which are both implanted in the collar 4 at both ends of the insulating bobbin 1. The distributed constant type delay line with the above configuration has a connection diagram as shown in _FIG .
Set the number of turns of the ground electrode windings 6 and 7 so as to obtain C ₂ , and set the number of turns and inductance so as to obtain the desired phase characteristics such as inductance L in signal winding 5 and inductance L' in signal winding 5. Minute L,
The ratio of L' is determined and wound. An equivalent circuit of the distributed constant type delay line having the above configuration is shown in FIG. In Fig. 5, L is the inductance of the signal winding 5, L' is the inductance of the signal winding 5', _C1 is the capacitance between the signal winding 5 or 5' and the ground electrode winding 7, and _C2 is the capacitance between the signal winding 5 or 5' and the ground electrode winding 7. C p1 is the capacitance between the signal winding 5 or 5' and the ground electrode winding 6, C _p1 is the bridging stray capacitance between the adjacent signal windings 5 and 5', and C _p2 is the signal winding with one signal winding skipped. The bridging stray capacitance between the wires, C _po indicates the bridging stray capacitance between the signal windings at both ends, K ₁ is the coupling coefficient between adjacent signal windings, and K ₂ is the signal that skips one signal winding. The coupling coefficient between the windings, K _o , indicates the coupling coefficient between the signal windings at both ends. Viewed from the input IN, the ground electrode winding 6 and the first
The signal winding ₅ of the stage forms a capacitance C2, this signal winding 5 forms an inductance L, this signal winding 5 and the ground electrode winding 7 form a capacitance _C1 , and then The ground electrode winding 6 and the signal winding ₅ ' of the stage form a capacitance C2, the signal winding 5' forms an inductance L', and the signal winding 5' and the ground electrode winding 7 form a capacitance C2. ₁ , the above are successively constructed, resulting in the equivalent circuit diagram shown in FIG. As described above, by determining the ratio of the number of turns in the signal windings 5 and 5' to obtain the inductances L and L', the coupling coefficients K ₁ , K ₂ ...K _o can be changed, resulting in Phase compensation is possible as follows. In addition, in the present invention, phase compensation is made possible by providing a difference in the number of turns of the signal windings 5 and 5', so the configuration of the earth electrode windings 6 and 7 is not limited to the above embodiment. . Next, an example of actual characteristics of the embodiment will be explained with reference to FIG. The characteristic example of A in Fig. 6 is the characteristic of a conventional distributed constant type delay line with an induced m-type coefficient m = 1.44.
That is, this is an example of the characteristic when the number of turns of the signal windings in adjacent grooves is the same. B is the turn ratio of the signal winding in the adjacent groove in an insulated bobbin with exactly the same shape as the conventional one.
This is an example of the characteristics when the winding induction m type coefficient m is 1.36 with a ratio of 100:80. Similarly, C is guided m at 100:50.
If the type coefficient m is 1.29, D is also 100:25.
This is an example of the characteristics when the winding induction m-type coefficient m = 1.22 at the ratio of . However, the above A to D are insulated bobbins with constant collar dimensions and different turn ratios of the signal windings in the adjacent grooves. The coupling coefficient K was measured, and each induced m-type coefficient m was calculated from the formula K=m ² -1/m ² +1. The above coupling coefficient K can be calculated by measuring the inductance L and L' of each signal winding, then measuring the total inductance L _T connecting the two signal windings, and using the general formula

Calculated using [Formula]. However, it is assumed that M=L _T -(L×L')/2. As mentioned above, the distributed constant type delay line of the present invention can perform phase compensation by simply adjusting the number of turns for each adjacent groove using the conventional same bobbin and same winding method.
Mass production is possible because it can be done using the same mass production method as before.
It has the advantage of being able to improve the phase characteristics without sacrificing cost and with the same shape as the conventional one.

[Brief explanation of drawings]

Fig. 1 is an equivalent circuit diagram of the lattice circuit, Fig. 2 is a group delay time characteristic diagram of the same, Fig. 3 is a sectional view of an embodiment of the distributed constant delay line of the present invention, and Fig. 4 is a connection diagram of the same. , FIG. 5 is an equivalent circuit diagram, and FIG. 6 is a group delay time characteristic diagram of an embodiment of the present invention. 1... Insulating bobbin, 2, 3... Winding groove, 4...
Tsuba, 5, 5'... Signal winding, 6, 7... Earth electrode winding, 8 to 10... Terminal.

Claims (1)

[Scope of utility model registration request] A ground electrode winding is provided in a winding groove of a bobbin in which a plurality of winding grooves are formed by a plurality of flanges, and a signal winding is provided by winding a conductive wire having an insulating coating in the same direction in the winding groove, Further, the distributed constant type delay line is configured such that the signal windings in adjacent winding grooves are alternately given a winding difference, and the number of turns in every other winding groove is made equal.