JPH09284155A - Tuner provided with distribution circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the tuner with a simple configuration and provided with an inexpensive distribution circuit in which handling of antenna input signal terminals and input terminals of a television receiver is easy. SOLUTION: A connection terminal receiving an input signal from an antenna and a connection terminal with a display device are not specified. Concretely, the distribution circuit has a 75ohm coupling strip circuit 11 having two-parallel conductor strips. One end of one conductor strip connects to an antenna and the other end is connected to one display device and both ends of the other strips are connected to an internal signal processing circuit 14 of the tuner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution circuit of a tuner for receiving a terrestrial wave and / or a satellite broadcast built in a video reproducing / recording device and the like, and more particularly to connecting an antenna and a display device such as a television receiver. The present invention relates to a tuner provided with a distribution circuit in which connection terminals for signal reception are made bidirectional.

[0002]

2. Description of the Related Art Conventionally, an input signal received by a tuner for terrestrial and / or satellite broadcasting is displayed on a display device, for example, a television receiver (TV), and an image reproducing / recording device, for example, a video tape recorder (tube recorder) having the tuner built therein. VT
In order to be able to receive both the R and R), a distribution circuit is provided at the input part of the tuner built in the video reproducing / recording device.

This distribution circuit has a function of distributing an input signal from an antenna to an internal signal processing circuit of the tuner and a television receiver, and an internal signal processing circuit of the tuner and a television receiving the input signal from the antenna. It must have a function of electrically isolating the receivers, that is, a function of preventing current from flowing between the tuner and the television receiver.

Therefore, in the conventional distribution circuit, as shown in FIG. 2, the RF input terminal 2 and the RF input terminal 2 provided in the input portion for receiving the input signal from the antenna of the satellite tuner 1 are used.
Output terminal 3, amplifier 4, two attenuators (ATT)
It is composed of 5 and 6.

The RF input terminal 2 is connected to an antenna (not shown), and the RF output terminal 3 is connected to an input terminal of a television receiver (not shown).

The amplifier 4 is an amplifier for compensating the distribution loss occurring in the attenuators 5 and 6 in advance, and its input terminal is connected to the RF input terminal 2, that is, the antenna. The output terminal of the amplifier 4 is connected to the input terminals of the attenuators 5 and 6. That is, the amplifier 4
Output is distributed to both attenuators 5, 6.

Since the attenuators 5 and 6 form an active circuit that distributes signals to the television receiver side and the image reproducing / recording device side, respectively, the input signal from the antenna is reproduced by the television receiver and the image reproducing device. The recording device and the recording device each flow in a specific one direction.

The output terminal of the attenuator 5 is the RF output terminal 3,
That is, it is connected to the television receiver, and the output terminal of the attenuator 6 is connected to the input terminal of the internal signal processing circuit 7 of the tuner 1.

The distribution circuit having such a configuration inputs the input signal from the antenna to the RF input terminal 2 and distributes it to the television receiver and the image reproducing / recording apparatus via the amplifier 4 and the attenuators 5 and 6. To do.

[0010]

However, in the terrestrial and / or satellite broadcast tuner having the above-mentioned conventional distribution circuit, the RF input terminal 2 and the RF output terminal 3 have fixed uses for input and output, respectively. Since there is no flexibility in use, it is necessary to distinguish the input terminal and the output terminal before connecting them, which causes a problem that handling is troublesome.

Further, since the distribution circuit is an active circuit composed of the amplifier 4 and the attenuators 5 and 6, the structure is complicated, and the number of parts is large and the cost is high.

Therefore, there is a problem in a tuner distribution circuit which is easy to handle the connection of terminals from the display device and the antenna, has a simple structure, and is low in cost.

[0013]

In order to solve the above-mentioned problems, a tuner provided with a bidirectional distribution circuit according to the present invention is
A tuner provided with a distribution circuit for distributing an input signal from an antenna to a display device and an internal signal processing circuit, for example, a tuner for satellite broadcasting, wherein the distribution circuit includes two electrically isolated conductor strips. Have 75Ω
By connecting the antenna and the display device to the connection terminals provided at both ends via the one conductor strip, and connecting the internal signal processing circuit to the other conductor strip. is there.

The tuner having the above-described structure can be used without specifying the terminal for receiving the input signal from the antenna.
Whichever is better, that is, without specifying the input / output,
If the tuner is connected to one terminal, the other terminal may be connected to the display device, which makes handling of the tuner extremely easy.

Further, since the 75Ω coupling strip circuit is a non-active circuit, the structure is simple and the number of parts can be reduced, so that the tuner distribution circuit can be manufactured at low cost.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of a tuner provided with a distribution circuit according to the present invention is a distribution for supplying a satellite broadcast reception signal to both a television receiver which is a display device and a video reproducing / recording device. Circuit.

As shown in FIG. 1, this distribution circuit 10A is arranged inside the input section of the satellite tuner 75.
The configuration includes an Ω coupling strip circuit 11 and two input / output terminals 12 and 13 attached to the outer surface of the satellite tuner 10.

The 75Ω coupling strip circuit 11 is a passive (non-active) circuit having a simple structure composed of two conductor strips 11a and 11b provided on the front and back surfaces of a dielectric plate (not shown) in parallel with each other. The conductor strip 11a becomes the primary side, and the conductor strip 11b becomes the secondary side. In addition, the primary side and the secondary side are completely electrically isolated.

One end of the conductor strip 11a is connected to the input / output terminal 12, and the other end is connected to the input / output terminal 13. The input / output terminals 12 and 13 are now connected via the conductor strip 11a. One end of the conductor strip 11b is connected to the input terminal of the internal signal processing circuit 14, and the other end is grounded.

The satellite tuner 10 having the distribution circuit 10A having the above structure is built in a television receiver or a video reproducing / recording apparatus. Either of them may be used, but for the sake of explanation, it is assumed that the satellite tuner 10 is built in the video reproducing / recording apparatus, and the operation will be described below.

When the input / output terminal 12 is connected as an output terminal to the television receiver and the input / output terminal 13 is connected as an input terminal to the antenna, the satellite broadcast reception signal input from the antenna is the conductor strip 11a as indicated by the white arrow.
And is supplied from the output terminal 12 to the television receiver. At the same time, an induced current is generated in the conductor strip 11b and is supplied to the internal signal processing circuit 14 of the satellite tuner 10 as shown by the white arrow.

When the input / output terminal 12 is connected as an input terminal to the antenna and the input / output terminal 13 is connected as an output terminal to the television receiver, the satellite broadcast reception signal input from the antenna is a conductor as indicated by a black arrow. Strip 1
It flows through 1a and is supplied from an output terminal 13 to a television receiver. At the same time, an induced current is generated in the conductor strip 11b and supplied to the internal signal processing circuit 14 of the satellite tuner 10 shown by the black arrow.

When the satellite tuner 10 is provided in the television receiver, it goes without saying that the explanation will be the interchange of the television receiver and the video reproducing / recording device described above.

[0024]

As described above, the tuner provided with the bidirectional distribution circuit according to the present invention has a 75Ω coupling consisting of two conductor strippers electrically isolated as a distribution circuit for distributing the input signal from the antenna. By using the strip circuit, both terminals can be used for input or output without specifying the terminal for inputting the input signal from the tuner, and the tuner is extremely easy to handle. There is.

Further, since it is composed of two electrically isolated conductor strippers, the structure is simple, and the number of parts is small, so that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a tuner including a distribution circuit according to the present invention.

FIG. 2 is an explanatory diagram showing a configuration of a conventional tuner distribution circuit.

[Explanation of symbols]

10: satellite tuner, 10A: distributor, 11: 75Ω coupling strip circuit, 11a, 11b: conductor strip,
12, 13: input / output terminals, 14: internal signal processing circuit

Claims (2)

[Claims] 1. A tuner having a distribution circuit for distributing an input signal from an antenna to a display device and an internal signal processing circuit in the tuner, wherein the distribution circuit has two electrically isolated lines. With conductor strips of 75
An Ω coupling strip circuit is provided, the antenna and the display device are connected to the connection terminals provided at both ends via the one conductor strip, and the internal signal processing circuit is connected to the other conductor strip. A tuner having a distribution circuit characterized by. 2. The tuner according to claim 1, wherein the tuner is a satellite broadcast tuner.