JPH10311850A - Measuring method for signal frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable miniaturization of a circuit board and enhance operating efficiency and the reliability of measurement. SOLUTION: In a method for measuring the frequency of a signal present in a space in the vicinity of a signal line 2 on a printed board 1 by positioning one end of an SJ cable 4 near the signal line 2 on the printed board 1 and connecting a spectrum analyzer to the other end of the SJ cable 4, a through hole 3 where a first opening 3a is located near the signal line 2 is provided in advance in the printed board 1 and the SJ cable 4 is inserted into the through hole 3 when the frequency of a signal is measured from a second opening 3b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal frequency measuring method suitable for measuring (confirming) the frequency of a high-frequency signal generated from a signal generating section of a circuit board in an electronic device.

[0002]

2. Description of the Related Art Generally, in an electronic device such as a communication device, a spectrum analyzer is used to measure the frequency of a signal existing in a space near a signal line or a signal oscillation source on a circuit board. .

Conventionally, the method of measuring the signal frequency of this kind includes:
A method of measuring a signal frequency by connecting a connector to a signal generation unit via a hybrid or the like and inserting a coaxial cable into the connector is adopted.

[0004] Conventional signal frequency measuring methods include:
A method of extracting a signal generating portion such as a signal line and a signal oscillating source by a pattern, bringing a probe into contact with a pad connected to the tip of the pattern, and measuring a signal frequency is also employed.

[0005]

However, in the former case, since a connector is used for measuring the signal frequency, a space for mounting the connector must be secured on the circuit board, and the entire circuit board is required. However, there was a problem that the size became large.

On the other hand, in the case of the latter, since a pattern is interposed between the signal generating section and the connector, spurious or noise is easily generated at the time of measuring the signal frequency, and the reliability of the measurement is increased. There is a disadvantage that the properties are reduced.

Further, when measuring the frequency of the signal, the operator needs to hold the probe, and there is a disadvantage that the working efficiency is reduced. Therefore, it is conceivable to solder a short lead wire to the pad and lock the probe to the lead wire for measurement. In this case, the pad may peel off from the circuit board due to the weight of the probe.

The present invention has been made in view of such circumstances, and provides a signal frequency measuring method capable of reducing the size of a circuit board and improving work efficiency and measurement reliability. With the goal.

[0009]

According to a first aspect of the present invention, there is provided a method of measuring a signal frequency, comprising the steps of:
A method for measuring a frequency of a signal existing in a space near a signal generating portion by positioning one end of a cable near a signal generating portion on a circuit board and connecting a spectrum analyzer to the other end of the cable. In advance, a through hole is provided in the circuit board in the vicinity of the signal generating section, the opening of which is located, and a cable is used to measure the frequency of the signal from the opening on the side opposite to the opening on the signal generating section side in the through hole. There is a way to insert.

According to a second aspect of the present invention, in the method for measuring a signal frequency according to the first aspect, before inserting the cable, a housing having a through hole is attached to the circuit board, and the cable is inserted into the through hole of the housing. Is inserted as a method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. FIG. 1 is a perspective view for explaining a signal frequency measuring method according to the first embodiment of the present invention. Referring to FIG. 1, a signal line 2 serving as a signal generator exposed on the back surface is formed on a printed circuit board as a circuit board for communication equipment indicated by reference numeral 1.

The printed circuit board 1 has a first opening 3a located near the signal line 2 and the first opening 3a.
a through-hole 3 having a second opening 3b located on the side opposite to
Is provided.

The through hole 3 of the printed circuit board 1
When measuring the signal frequency generated in the space near the signal line 2, one end (core wire) of the SJ cable 4 is connected to the second opening 3b.
Inserted from and held.

The opening diameter of the through hole 3 is set to be larger than the core wire diameter of the SJ cable 4.
Is set to a size smaller than the outer diameter. The other end (connector) of the SJ cable 4 is connected to a spectrum analyzer (not shown).

Next, a signal frequency measuring method according to this embodiment will be described with reference to FIG. First, a through hole 3 in which a second opening 3a is located near a signal line 2 is provided in a printed circuit board 1.

Next, when measuring the signal frequency, the SJ cable 4 is inserted into the through hole 3 from the second opening 3b. In this manner, the frequency of a signal existing in the space near the signal line can be measured.

That is, one end of the SJ cable 4 is positioned near the signal line 2 on the printed circuit board 1,
This is a method of connecting a spectrum analyzer (not shown) to the other end of the SJ cable 4 to measure the frequency of a signal existing in the space near the signal line. The SJ cable 4 is inserted into the through hole 3 in which the first opening 3a is located, and when measuring the frequency of the signal from the second opening 3b in the through hole 3.

Therefore, in this embodiment, SJ
Since the cable 4 functions as an antenna and the signal frequency existing in the space near the signal line 2 is measured, the space for mounting the connector on the printed circuit board 1 which is conventionally required for measuring the signal frequency is not required.

Further, in the present embodiment, since no signal frequency measuring pattern is interposed between the signal generating section and the connector, spurious and noise are not generated unlike the related art.

Further, in this embodiment, when measuring the frequency of the signal, the SJ is inserted into the through hole 3 of the printed circuit board 1.
Since the cable 4 is inserted, when measuring the signal frequency, SJ
There is no need for the operator to hold the cable 4.

In addition, in the present embodiment, since the signal line 2 and the peripheral circuits do not come into contact with each other when measuring the signal frequency, there is no risk of damaging electronic components on the printed circuit board 1.

Next, a method of measuring a signal frequency according to a second embodiment of the present invention will be described with reference to FIG. FIG.
Is a cross-sectional view for explaining a signal frequency measuring method according to the second embodiment of the present invention, in which the same members as those in FIG. 1 are denoted by the same reference numerals, and detailed description is omitted. In FIG. 1, a housing denoted by reference numeral 11 includes upper and lower housings 12 and 13, and is attached to the printed circuit board 1.

The upper casing 12 is provided with a through hole 14 which opens in the axial direction of the through hole 3 and through which the SJ cable 4 is inserted. The SJ cable 4 is inserted and held in the through hole 14 of the upper housing 12. Thereby, the cable portion between the cable connector and the spectrum analyzer (not shown) is held.

The upper case 12 has an opening 3 through which an electronic component 15 mounted on the printed circuit board 1 is housed. On the other hand, in the lower housing 13, the through-hole 3 is opened, and the signal line 2 is housed.

Next, a signal frequency measuring method according to the present embodiment will be described with reference to FIG.
One end of the SJ cable 4 is positioned near the signal line 2 on the printed circuit board 1, and a spectrum analyzer (not shown) is connected to the other end of the SJ cable 4 to connect a signal existing in a space near the signal line. A through hole 3 in which a first opening 3a is located near a signal line 2 in a printed circuit board 1 and a through hole 13 opening in the axial direction of the through hole 3. The upper housing 12 is mounted on the printed circuit board 1 and the SJ cable 4 is inserted into the through hole 13 when measuring the frequency of a signal.
After that, the SJ is inserted into the through hole 3 through the second opening 3b.
The cable 4 is inserted.

Therefore, in the present embodiment, no space is required on the printed circuit board 1 for mounting a connector, no spurious noise or noise is generated, and the operator connects the SJ cable 4 when measuring the signal frequency. The fact that there is no need to hold and that there is no risk of damaging electronic components and the like on the printed circuit board is the same as in the first embodiment, but the holding capacity of the SJ cable 4 is the same as that of the first embodiment. Since the SJ cable 4 can be inserted and held in the first embodiment, the height can be further increased as compared with the first embodiment.

In each of the embodiments, an example has been described in which the frequency of a signal existing in the space near the signal generating unit is measured on a circuit board for communication equipment, but the present invention is not limited to this. However, it is needless to say that the present invention can be applied to a circuit board for another electronic device in the same manner as in the embodiment.

[0028]

As described above, according to the present invention, the circuit board is provided with a through hole in which the opening is located in the vicinity of the signal generating section, and the opening on the signal generating section side is formed in the through hole. Since the cable is inserted when measuring the frequency of the signal from the opposite opening, the cable functions as an antenna.

Therefore, since the signal frequency in the vicinity of the signal line is measured, the space for mounting the connector conventionally required for measuring the signal frequency becomes unnecessary on the connector.
The size of the circuit board can be reduced.

Further, since no signal frequency measuring pattern is interposed between the signal generating section and the connector, spurious and noise are not generated unlike the conventional art, and the reliability in measurement is improved. be able to.

Furthermore, since the cable is inserted into the through hole of the circuit board when measuring the signal frequency, it is not necessary for the operator to hold the cable when measuring the signal frequency, and the working efficiency can be improved. it can.

Another advantage is that there is no possibility of damaging electronic components and the like on the circuit board since the signal generator and the like are not contacted when measuring the signal frequency.

According to the second aspect of the present invention, since the cable is inserted through the through-hole of the housing, the capability of holding the cable when measuring the signal frequency can be further enhanced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a method for measuring a signal frequency according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a method for measuring a signal frequency according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Signal line 3 Through-hole 3a First opening 3b Second opening 4 SJ cable

Claims (2)

[Claims] An end of a cable is positioned in the vicinity of a signal generator on a circuit board, and a spectrum analyzer is connected to the other end of the cable to reduce a frequency of a signal existing in a space near the signal generator. A method for measuring, wherein a through hole having an opening located in the vicinity of the signal generating portion is provided on the circuit board in advance, and a frequency of a signal is measured in the through hole from an opening opposite to the opening. A method of measuring a signal frequency, comprising inserting the cable when performing the measurement. 2. A circuit having a through-hole that opens in the axial direction of the through-hole is attached to the circuit board before inserting the cable, and the cable is inserted through the through-hole of the housing. The method for measuring a signal frequency according to claim 1, wherein