JPH1117573A - Low noise block converter for satellite broadcast - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the production efficiency of the low noise block converter for satellite broadcast and to reduce the cost. SOLUTION: A main frame 12 of a low noise block converter 11 is press stamped of a steel plate. A board 28 is placed horizontally in the main frame 12 and a cup-shaped shield case 31 (32) is covered on a low noise amplifier section 29 (local oscillating circuit section 30) on the front side of the board respectively. Moreover, in the case of covering a cover 13 to an upper part of the frame 12 and a cover 14 to a lower part of the frame 12, claws 15, 15,... of the covers 13, 14 are locked to a rib 16 of the main frame 12. Furthermore, a square waveguide 20 is screwed to a front face of the main frame 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a low noise block converter for satellite broadcasting, and more particularly to a low noise block converter attached to a flat antenna for satellite broadcasting.

[0002]

2. Description of the Related Art In a conventional low noise block converter for satellite broadcasting, a box-shaped main frame and a waveguide portion are integrally formed of aluminum or zinc by die casting. Then, the board is assembled on the inner surface of the main frame, and a plate-shaped cover is put on the opening of the main frame and screwed.

[0003]

Since the die casting requires a certain period of time until the aluminum and zinc materials are cooled and hardened, there is a physical limit to increasing the production quantity per hour. Therefore, it is difficult to reduce the product price.

[0004] Therefore, by increasing the production quantity per hour, there arises a technical problem to be solved in order to reduce the price of this type of low noise block converter for satellite broadcasting, and the present invention solves this problem. The purpose is to solve.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above-mentioned problems. A substrate is mounted on a main frame formed by press-molding a metal plate. A shield case is mounted on each of the low-noise amplifier section and the local oscillation circuit section, and a rib is protruded along the upper and lower edges of the side surface of the main frame. The present invention provides a low noise block converter for satellite broadcasting in which covers are covered on the upper and lower sides of a main frame, and a waveguide is fixed to one side of the main frame with screws.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention.
6 to FIG. The figure shows a low noise block converter 11 for satellite broadcasting. The main frame 12 is formed in a rectangular frame shape by pressing a steel plate and plated with nickel or tin. Similarly, the covers 13 and 14 attached to the upper and lower portions of the main frame 12 are also formed by press-molding a steel plate and plated with nickel or tin.

The four edges of the covers 13 and 14 are formed in a square wave shape, bent inward and downward, and the claws 15, 15... It is bent in the shape of a letter. On the other hand, linear ribs 16 protrude from the four side surfaces of the main frame 12 along the upper edge and the lower edge, respectively. When the covers 13 and 14 are covered on the upper and lower sides of the main frame 12, the claws 15, 15... be able to.

Further, at the upper end edge of the main frame 12, projections 17, 17... Are provided at predetermined locations, and near the edge of the upper cover 13, slits 18 opposing the projections 17, 17. , 18 ... are perforated. And
When the cover 13 is mounted on the main frame 12, the projection 1
7 projects upward through the slit 18. The main frame 12 and the cover 13 are caulked by bending the protruding portion of the protrusion 17 into an S shape along the width direction.

Bosses 19 with screw holes are provided on the front surface of the main frame 12 on both left and right sides. And
A rectangular waveguide 20 is provided in front of the main frame 12. On the left and right sides of the base of the rectangular waveguide 20, there are provided upper and lower two-stepped pedestals 21, 21.
Screw holes 22, which penetrate to the back,
22 is perforated. The screw holes 22, 22 are overlapped with the screw holes of the bosses 19, 19, and the screws 23, 23
Is screwed, the rectangular waveguide 20 is fixed to the main frame 12.

Screw holes 24, 24 are also formed in the lower surfaces of the stepped pedestals 21, 21. This screw hole 2
Reference numerals 4 and 24 are for mounting the low-noise block converter 11 in the back housing of the flat antenna (not shown), and are formed in a bag shape. The screw holes 26 formed in the protruding pieces 25 projecting rearward from the left and right central portions of the lower end edge of the low noise block converter 11 also serve the same role as the screw holes 24, 24. .

Further, the upper end of the rectangular waveguide 20 protrudes in the left-right direction, and screw holes 27, 27
Has been perforated. The screw holes 27 are for mounting a reflection mount (not shown).

A substrate 28 is horizontally mounted in the main frame 12 at a substantially vertical intermediate position.
On the surface of the substrate 28, in addition to a low noise amplifier unit 29 and a local oscillation circuit unit 30, a HEMT, a band-pass filter,
Various electronic circuits such as a mixer and an IF amplifier are mounted. Among these electronic circuits, a high-frequency current exceeding 10 GHz flows through the low noise amplifier section 29 and the local oscillation circuit section 30. Therefore, the low noise amplifier section 29 and the local oscillation circuit section 30 are each provided with a cup-shaped shield case 3.
1, 32 are mounted. This makes it possible to reliably prevent the leakage of the high-frequency signal.

The peripheral edges of the shield cases 31, 32 are placed on the ground pattern of the substrate 28 and soldered. In addition, an aluminum plate 33 for protecting the substrate, which also serves as a ground plane, is laid on the lower surface of the substrate 28 before mounting. Thereby, the flatness of the substrate 28 is maintained,
No stress is applied to the mounted components. The support pieces 3 projecting from the bottom plate and side plates of the main frame 12 are provided.
The aluminum plate 33 is supported and fixed at 4, 34. The lower surface of the aluminum plate 33 is provided with a three-terminal power circuit IC3.
5 and the F connector 36 are suspended, and the F connector 3
Reference numeral 6 penetrates through the main frame 12 and the cover 14 and protrudes below the low noise block converter 11.

Further, a pickup pin 37 projects forward from the front edge of the substrate 30. On the other hand, a circular hole 38 is formed in the center of the front surface of the main frame 12,
A boss 39 having a hole is provided at the center of the back surface of the rectangular waveguide 20 so as to face the circular hole 38. The pickup pin 37 penetrates through the circular hole 38 and the hole of the boss 39 to reach the inner cavity of the rectangular waveguide 20.

Thus, the satellite broadcasting radio wave of the 12 GHz band received by the flat antenna is guided by the rectangular waveguide 20, converges on the pickup pin 37, and is taken into the substrate 28. The signal is amplified by the low-noise amplifier 29 while maintaining a good S / N ratio, and then frequency-converted to a 1 GHz band by the local oscillation circuit 30 and a mixer via a hand-pass filter. Amplification and impedance matching are performed by the IF amplifier. Then, the signal is output to an indoor tuner via a coaxial cable connected to the F connector 36.

The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0017]

As described above, according to the present invention, the main frame is formed by press molding instead of the conventional die casting, so that a cooling period of the main frame is not required.
In addition, if the cover is covered on the upper and lower sides of the main frame, the claws of the cover can be hooked on the ribs of the main frame and can be easily fitted. Thereby, the production line can be made more efficient, and the production quantity per hour can be increased as much as possible. Therefore, the product price can be significantly reduced.

On the other hand, in the case structure of such a press, there is a problem of leakage of a high frequency signal. No problems occur.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a rear view of the same.

FIG. 3 is a side view of the same.

FIG. 4 is a plan view of the same.

FIG. 5 is a bottom view of the same.

FIG. 6 is a sectional view taken along line AA of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Low noise block converter 12 Main frame 13, 14 Cover 15 Claw 16 Rib 20 Rectangular waveguide 23 Screw 28 Substrate 29 Low noise amplifier part 30 Local oscillation circuit part 31, 32 Shield case

Claims (1)

[Claims] 1. A board is mounted on a main frame formed by press-molding a metal plate, and a low-noise amplifier section and a local oscillation circuit section on the board are covered with shield cases, respectively. A rib is projected along the upper and lower edges of the side surface of the main frame, and a hook is provided on the rib to project upward and downward from the edge of the cover to cover the cover on the upper and lower sides of the main frame. A low noise block converter for satellite broadcasting, wherein a waveguide is fixed to one side of a main frame with screws.