JPH0242826A - Radio receiver - Google Patents

Abstract

PURPOSE:To execute the switch of a diversity reception condition and a non- diversity reception condition only with the attaching/detaching of a sub antenna terminal to/from a sub antenna input terminal by providing a changing-over switch, which has a movable contact, and a switching device, etc. CONSTITUTION:When a terminal 20 of a sub antenna is not inserted to a sub antenna input terminal 12, a lever 15 of a changing-over switch 14, which is interlocked with the attaching/detaching of the terminal 20, is depressed and a movable contact 16 is connected with a fixed terminal 17. Thus, a switching transistor TRQ1 goes to a conductive condition and through a diode 1, in the internal part of a switching device 13, the antenna is forcibly fixed to a main antenna side. Then, the non-diversity reception condition is obtained. On the other hand, when the terminal 20 is inserted to the terminal 12, the lever 15 is depressed and the contact 16 is connected with a fixed terminal 18. Then, the TRQ1 goes to a non-conductive condition and through the diode D1, in the internal part of the device 13, the forcible fixing to the main antenna side is released. Then, the diversity reception condition is obtained. Accordingly, the switch of the reception condition can be executed only by the attaching/ detaching of the terminal 20 to/from the terminal 21.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a radio receiver such as a car radio equipped with a diversity receiving device.

Conventional technology In diversity reception, a switching device for the diversity main antenna and the sub-antenna changes the voltage induced in the antenna depending on the magnitude of the voltage induced in each of the main antenna and the sub-antenna that are separated by a certain distance. This is a reception method that switches to select the one with the largest value, so that the best reception condition is always maintained.

If this reception method is suitable for a car radio etc. installed in a mobile object such as a car, the main antenna as the car moves, etc.
Since the voltage induced in the sub-antenna changes depending on the distance from the radio wave transmission point and obstacles such as buildings, reception is very effective.

However, radio receivers such as car radios equipped with such diversity receiving devices are generally dedicated as diversity receivers, and a type that can be used by switching between diversity reception state and non-diversity reception state has not been put into practical use. do not have.

However, even when receiving radio in a car that only has a so-called main antenna other than a car that has two antennas, a main antenna and a sub antenna, diversity reception can be achieved by leaving the sub antenna input terminal open with a switch. Radio reception can be performed by switching the state to non-globality reception state.

Problems to be Solved by the Invention However, in the above-mentioned conventional radio receiver, there is an inconvenience in that even if the receiver is in the diversity reception state, it becomes a non-diversity reception state if, for example, the user forgets to switch the changeover switch.

In addition, when using the device without the sub-antenna set to support non-diversity reception, unless the receiving antenna setting is switched to the main antenna and fixed, - Since there is an inconvenience that the antenna is occasionally switched to the sub-antenna side, there is a problem in that it becomes susceptible to the effects of switching noise and the like.

The present invention solves these conventional problems,
It is an object of the present invention to provide a radio receiver equipped with a diversity receiving device capable of switching between a diversity receiving state and a non-diversity receiving state simply by inserting and removing a terminal of a sub-antenna with respect to an input terminal of the sub-antenna.

Means for Solving the Problems In order to achieve the above object, the present invention provides a diversity reception state by inserting the terminal of the sub-antenna into the sub-antenna input terminal, and a state in which the terminal of the sub-antenna is removed from the sub-antenna input terminal. A changeover switch is provided at the subantenna input terminal that expands in conjunction with insertion/removal of the subantenna terminal so that a non-diversity reception state is entered, and opening and closing of this switch switches between a diversity reception state and a non-diversity reception state. It is equipped with a device.

Therefore, according to the present invention, the changeover switch opens and closes in conjunction with insertion and removal of the terminal of the subantenna into the subantenna input terminal, and the changeover device changes the diversity reception state in response to the opening and closing operations of the changeover switch. This has the effect of reliably preventing inconveniences such as forgetting to switch between the diversity reception state and non-diversity reception state and switching errors.

Embodiment The figure shows the configuration of an embodiment of the present invention, and is a schematic block diagram of a switching section that switches between a diversity reception state and a non-diversity reception state of a radio receiver equipped with a diversity reception device.

In the figure, 11 is a main antenna input terminal, 12 is a sub-antenna input terminal, 13 is a switching device for diversity main antenna and sub-antenna, and 14 is provided at the sub-antenna input terminal, and is linked to the insertion and removal of the terminal of the sub-antenna. 15 is a lever of the changeover switch 14;
16 is a movable contact of the changeover switch 14, and 17 and 18 are fixed terminals connected to the movable contact 16 of the changeover switch 14, respectively.

19 is the terminal of the main antenna, 20 is the terminal of the sub antenna, 2
1 is a contact piece provided within the main antenna input terminal 11 so as to make contact with the inserted terminal 19 of the main antenna; 22;
is a contact piece provided in the sub antenna terminal 12 so as to be in contact with the terminal 20 of the inserted sub antenna, 23 is a high frequency amplification section, 24 is an output terminal, and C1 and C2 are the switching device 13 and the contact piece, respectively. The capacitors R1 and R2 are each connected in series between the movable contact 16 and the control voltage VCC application terminal 25, and Ql is a switching transistor. The base of this switching transistor Q1 is a voltage dividing resistor R
The emitter is connected to the connection point P between 1 and R2, and the emitter is connected to the application terminal 2.
5, and its collector is connected to a switching device 13 via a diode D1.

Next, the operation of the above embodiment will be explained.

In the above embodiment, when the terminal 20 of the sub antenna is not inserted into the sub antenna input terminal 12, the lever 15 of the changeover switch 14 provided at the sub antenna input terminal 12 is not pressed down. The movable contact 16 of the changeover switch 14 is connected to the fixed terminal 17.

In this state, the switching transistor Q1 is in a conductive state because the base resistor R1 is grounded via the movable contact 16 of the changeover switch 14, and the control voltage is applied to the antenna switching device 13 of the diversity main antenna and the sub antenna via the diode D1. By applying Vcc,
Inside the switching device 13, the antenna is forcibly fixed to the main antenna side.

As a result, if the terminal 20 of the sub antenna is not inserted into the sub antenna input terminal 12, the antenna switching device 13
is fixed to the main antenna side, resulting in a non-diversity reception state.

On the other hand, the terminal 20 of the sub antenna is connected to the sub antenna input terminal 12.
, the lever 15 of the changeover switch 14 provided at the sub-antenna input terminal 12 is pushed down, the movable contact 16 of the changeover switch 14 is connected to the fixed terminal 18, and the pace resistor R1 of the switching transistor Ql is opened. state.

Therefore, the base bias of the switching transistor Ql changes and becomes non-conductive, and the control voltage Vcc applied via the diode D1 decreases, causing the switching device 13 to become non-conductive.
Internally, the antenna is released from being forcibly fixed to the main antenna side, and enters a diversity reception state.

Effects of the Invention As is clear from the above embodiment, the present invention is capable of automatically switching between the diversity reception state and the non-diversity reception state by inserting and removing the terminal of the sub-antenna into the sub-antenna input terminal. and forgot to switch between diversity reception state and non-diversity reception state,
This has the effect of reliably preventing inconveniences such as switching errors.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of a switching unit that switches between a diversity reception state and a non-diversity reception state of a radio receiver equipped with a diversity reception device according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 11... Main antenna input terminal, 12... Sub antenna input terminal, 13... Switching device, 14... Changeover switch, 19... Main antenna terminal, 20... Sub antenna terminal. Name of agent: Patent attorney Shigetaka Awano and one other person Procedural amendment (4゛) November 1988 110

Claims (1)

[Claims] A main antenna input terminal for inserting and removing the terminal of the main antenna, a sub-antenna input terminal for inserting and removing the terminal of the sub-antenna, and a sub-antenna input terminal that is provided at the sub-antenna input terminal and opens and closes in conjunction with the insertion and removal of the terminal of the sub-antenna. A radio receiver equipped with a diversity receiving device including a changeover switch and a changeover device that switches between a diversity reception state and a non-diversity reception state by opening and closing the changeover switch.