JP2673838B2 - Radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] Receiving signals stored in a memory by sweeping a reception frequency band, storing receivable broadcast wave frequencies in a memory, and operating a preset switch corresponding to the memory. In a radio receiver having an auto memory function for receiving frequencies, the receivable frequency is stored in the auxiliary memory during the operation of the auto memory, and the contents of the auxiliary memory are written in the preset memory after the operation of the auto memory is completed. Prevents inappropriate modification of preset memory contents due to cancellation of auto memory operation during operation.

[Industrial technical field]

The present invention relates to a radio receiver, and in particular, a broadcast wave frequency that can be received by sweeping a reception frequency band and received is stored in a memory, and the reception stored in the memory by operating a preset switch corresponding to the memory. The present invention relates to an auto memory function that can receive frequencies.

[Conventional technology]

Conventionally, a receiver having a preset memory function, that is, a function of storing reception frequency information in a preset memory according to a preset switch and receiving at a reception frequency stored in a corresponding preset memory when the preset switch is operated Is used. A more convenient function is the auto preset function. this is,
The function of receiving the received frequency stored in the preset memory by operating the preset switch corresponding to the preset memory by sweeping the reception frequency band and storing the receivable broadcast wave frequency in the preset memory, The memory function automatically performs the operation of storing the reception frequency in the preset memory, and is particularly useful for a vehicle-mounted receiver whose reception area changes.

[Problems to be solved by the invention]

However, when the auto memory function is activated, the contents of the preset memory are rewritten sequentially as soon as the receivable reception frequency is detected, so if the auto memory function is canceled in the middle, the contents of the preset memory will be the same as the previous preset contents. There is a problem in that the contents of the latest auto memory operation are mixed and an inappropriate storage state occurs.

[Means for solving the problem]

The present invention solves such a problem by storing a broadcast wave frequency that can be swept and received in a reception frequency band in a preset memory and operating a preset switch corresponding to the preset memory. In a radio receiver with an auto memory function that receives the reception frequency stored in, the auxiliary memory that stores the reception frequency determined to be receivable by the sweep reception and the completion of the sweep reception in the reception frequency band are detected. Writing means for writing the contents of the auxiliary memory to the preset memory after the sweep reception of the reception frequency band is completed.

[Action]

Since the preset memory is written after the auto memory operation is completed, if the operation of the auto memory function is completed, the reception frequency by the auto memory function is written to the preset memory and the operation of the auto memory function is interrupted. When it is released, the preset memory is not written and the previous contents remain, so that an appropriate reception frequency is always stored in the preset memory, and the operability is improved.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, which will be described below with reference to this drawing. The radio receiver of this embodiment amplifies an antenna 1, a high frequency amplifier circuit, a mixing circuit for mixing the output of the high frequency amplifier circuit with a local oscillation signal of a local oscillation circuit, and an intermediate frequency signal frequency-converted by the mixing circuit. It comprises a front end 2 composed of an intermediate frequency amplifier circuit, and a dual-purpose detection circuit 3 for converting an output signal from the front end 2 into an audio signal. The audio signal from the detection circuit 3 is amplified by the amplifier 4 and output from the speaker 5. The microcomputer 6 controls the receiver, controls the reception frequency, and controls the preset memory operation.

The reception frequency is controlled by outputting a signal instructing the reception frequency to the front end 2.

This controls the oscillation frequency of the local oscillation circuit of the front end 2, and is performed by outputting the frequency division ratio to the variable frequency dividing circuit in the PLL circuit that constitutes the local oscillation circuit. In addition, the preset memory function reads and writes frequency information corresponding to the preset memory of the operation switch 8 in the RAM (random access memory) 7 by time management.

Next, the auto preset operation in this embodiment will be described with reference to the flowchart showing the operation of the microcomputer 6 in FIG. When the auto memory operation is performed, the signal that indicates the reception frequency to be output to the front end 2 is initialized [Set to the lowest frequency within the reception frequency band: the frequency division ratio (N value) given to the variable frequency division circuit in the PLL circuit is set. Setting to a value corresponding to the lowest frequency in the reception frequency band] is performed, and the process proceeds to step S1. In step S1, it is determined from the IFD signal whether or not there is a broadcasting station at the reception frequency. This IFD signal is a signal indicating whether the output signal of the front end 2, that is, the output signal of the intermediate frequency amplifier circuit exists (is above a predetermined level), and the reception frequency such as the method of detecting the output signal of the front end 2 Can be obtained by any known method of detecting a carrier wave at. If it is determined in step S1 that there is a broadcasting station, the process proceeds to step S2 to determine the electric field strength of the received broadcast wave. This is determined by a signal indicating the level of a carrier wave called a signal (S) level signal, and this S level signal can also be obtained as a detected rectified output of the output signal of the front end 2 (intermediate frequency amplification circuit). . Also,
If it is determined in step S1 that there is no broadcasting station, the process proceeds to step S6. In step S3, it is determined whether the number of broadcast stations detected by the auto preset operation is greater than or equal to the number of preset switches. To reduce (sort processing). If it is determined in step S3 that the number of broadcast stations detected by the auto preset operation is less than the number of preset switches, the process proceeds to step S5. Then, in step S5, the frequency data and the received electric field intensity data of these broadcasting stations are written in the auxiliary memory in association with each other. In step S6, it is determined whether or not the reception frequency in the auto memory operation has reached the upper limit frequency of the reception frequency band, and if it does not reach the upper limit frequency, the reception frequency is set to the next frequency and the process proceeds to step S1. The operations of steps S1 to S7 are continued until the upper limit of the band is reached. Then, if the reception frequency reaches the upper limit frequency in step S6, that is, if the sweep of the entire reception frequency band is completed, the process proceeds to step S8, the contents of the auxiliary memory are written in the preset memory, and the operation of the auto memory function ends.

According to the present embodiment having the above-described configuration, the reception frequency stored in correspondence with the preset switch cannot be rewritten unless the operation of the auto memory function is completed, so the operation of the auto memory function is canceled during the operation. However, the preset memory retains a state in which an appropriate reception frequency is stored.

〔The invention's effect〕

As described in detail above, according to the present invention, the broadcast wave frequencies that can be swept and received in the reception frequency band and are received are stored in the memory, and are stored in the memory by operating the preset switch corresponding to the memory. In a radio receiver with an auto memory function that receives the specified reception frequency, the receivable frequency is stored in the auxiliary memory during the operation of the auto memory, and the contents of the auxiliary memory are written in the preset memory after the auto memory operation is completed. It is possible to prevent the inappropriate change of the preset memory contents due to the cancellation of the automatic memory operation during the automatic memory operation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a flow chart showing the operation of the microcomputer 6. In the figure, 2 is a front end, 3 is a detection circuit, 6 is a microcomputer, and 7 is a RAM.

Claims (1)

(57) [Claims] 1. A sweep frequency reception of a reception frequency band, a receivable broadcast wave frequency is stored in a preset memory, and a reception frequency stored in the memory is received by operating a preset switch corresponding to the preset memory. In a radio receiver with an auto memory function, an auxiliary memory that stores the reception frequency determined to be receivable by sweep reception and the completion of sweep reception in the reception frequency band are detected, and after completion of sweep reception in the reception frequency band. A radio receiver comprising: writing means for writing the contents of the auxiliary memory into the preset memory.