JPH0318270B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an improvement in an audio input selection device that outputs a desired input signal from among a plurality of input signals by switching an input selection switch.

Conventional configuration and its problems Conventionally, in an audio input selection device in which each output terminal of a radio receiver, tape recorder, record player, etc. is connected to an input terminal, the reception frequency band switching switch of the radio receiver or the reception An audio input selection device has been proposed in which when a frequency tuning switch or dial is operated, a mute signal is output from a radio receiver and the input selection switch is switched to radio input. If you accidentally operate a dial on the radio receiver while recording an input signal from a recorder player or other device other than the radio receiver to the tape recorder without turning off the power to the radio receiver, the input selection switch may change to radio input. This has the drawback that the input signal from the radio receiver is recorded onto the magnetic tape from the middle of the record playback signal.

Purpose of the Invention In order to eliminate the drawbacks of the conventional example, the present invention has been made to prevent the input selection switch from switching to radio input even if the dial, etc. of the radio receiver is operated while the tape recorder is in the recording state. The present invention provides an audio input selection device with the following features.

Structure of the Invention The present invention provides that when the reception frequency band of a radio receiver is switched to a desired radio broadcast transmission frequency band, or when the reception frequency of the radio receiver is tuned to any radio broadcast transmission frequency, the radio reception A means is provided for outputting a mute signal from the receiver, and for outputting an input signal from the radio receiver by switching an input selection switch to radio input, and for recording input signals from sources other than the radio receiver, such as a tape recorder, on the tape recorder. means for preventing the input selection switch from being switched to radio input by the output of the recording operation circuit of the tape recorder even if the reception frequency band or reception frequency of the radio receiver is changed. It was established.

DESCRIPTION OF EMBODIMENTS The figure shows the configuration of an embodiment of the present invention.
1 is a radio receiver capable of receiving AM and FM broadcasts, 2 is a receiving antenna of the radio receiver 1, 3 is a radio broadcast receiving circuit of the radio receiver 1, 4 is a tuning circuit of the radio receiver 1, This tuning circuit 4 includes a crystal oscillator 5 and a synthesizer system that outputs a mute signal from an output terminal 6a to the radio broadcast receiving circuit 3 when the reception frequency band is switched or when the reception frequency is tuned to one of the radio broadcast transmission frequencies. The switch group 7 includes a phase locked loop integrated circuit 6, a frequency band changeover switch, a plurality of channel selection switches, a tuning switch, and a memory switch.
8 is an audio playback device, 9 is an input selection device of the audio playback device 8, and this input selection device 9 is:
The radio broadcast receiving circuit 3 is connected to the input terminal 11a, the tape recorder 10 is connected to the input terminal 11b, and the input terminal 1
A recorder player (not shown) is connected to each of the electronic switch circuits 11 and 1c, and an input terminal 11d is used as an auxiliary input. An integrated circuit 12 for output switching, a switch 13a for radio input, one of which is connected to the input terminal of the integrated circuit 12 and the other grounded, a switch 13b for tape playback input, and a switch 13b for phono input. switch 1
3c and an input selection switch 13 consisting of an auxiliary input switch 13d. 14 is a power amplification circuit of the audio reproducing device 8, and 15 is a speaker. 16 is a light emitting diode for indicating the recording operation of the tape recorder 10; 17 is connected at its base to the output terminal 6a via a level setting resistor 18; its emitter is grounded; and its collector is connected to the input terminal of the integrated circuit 12 and the radio Input switch 1
The switching transistor 19 connected to the connection point 3a has its base grounded to the recording operation output terminal 10a of the tape recorder 10 via the level setting resistor 20, and its emitter grounded.
This is a switching transistor whose collector is connected to the base of the transistor 17.

In this embodiment configured in this way, a desired switch 13a, 13 of the input selection switches 13 is selected.
If you press b, 13c or 13d, the integrated circuit 12
Since the corresponding input terminal of the input terminal is grounded and the input terminal becomes a low level, the electronic switch circuit 11 switches to the desired input so that the input signal from the radio input, tape playback input, phono input or auxiliary input becomes electronic. It is output from the switch circuit 11. Also, the reception frequency band of the radio receiver 1 can be changed by using the frequency band changeover switch of the radio receiver 1, or the reception frequency of the radio receiver 1 can be changed by using the channel selection switch or tuning switch of the radio receiver 1. When tuned to the radio broadcast transmission frequency,
A mute signal is output from the phased locked loop integrated circuit 6 and the transistor 17 conducts, so that the input terminal of the integrated circuit 12 is grounded and its input terminal becomes a low level, and the electronic switch circuit 11 is connected to the radio input. Then, the input signal from the radio input is outputted from the electronic switch circuit 11.

Next, when the electronic switch circuit 11 selects the phono input and records the phono input on the tape recorder 10, an output appears at the recording operation output terminal 10a of the tape recorder 10, and the light emitting diode 16 emits light. At the same time, transistor 19 becomes conductive, the base of transistor 17 is grounded, and transistor 17 becomes non-conductive. Therefore, even if the reception frequency of the radio receiver 1 is changed without turning off the power to the radio receiver 1, the input terminal of the integrated circuit 12 is not grounded, and the electronic switch circuit 11 continues to output the phono input.

Effects of the Invention According to the present invention, when you want to listen to the radio,
Even without operating the switch on the input selection device, just by operating the reception frequency band selection switch or reception frequency tuning switch or dial on the radio receiver, the input selection device switches to radio input and you can listen to radio broadcasts. This simplifies the switching operation and, for example, when recording the playback signal from a record player onto a tape recorder, even if the radio receiver's dial etc. are operated while the radio receiver's power is on, the tape will not be switched. To provide an audio input selection device in which a radio broadcast is not recorded on a magnetic tape of a recorder from the middle.

[Brief explanation of drawings]

The figure is a circuit diagram showing the configuration of an embodiment of the present invention. 1... Radio receiver, 4... Tuning circuit, 6...
Phase locked loop integrated circuit, 7... switch group, 9... input selection device, 11... electronic switch circuit, 12... integrated circuit for switching, 13... input selection switch, 10... tape recorder, 17,19...transistor.

Claims (1)

[Claims] 1. An input selection device that outputs a desired input signal from among a plurality of input signals by switching an input selection switch, and an input selection device that switches the reception frequency band of a radio receiver to a desired radio broadcast transmission frequency band, or When the reception frequency of the receiver is tuned to one of the radio broadcast transmission frequencies, the radio receiver outputs a mute signal, the input selection switch is switched to radio input, and the input signal from the radio receiver is output. When an input signal other than a radio receiver such as a record player is being recorded on a tape recorder or the like, the recording operation of the tape recorder will not be affected even if the receiving frequency band of the radio receiver or the receiving frequency is changed. 1. An audio input selection device comprising: means for preventing the input selection switch from switching to radio input due to the output of the circuit.