JPH0462501B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a radio broadcast quality control device, and particularly to a radio broadcast quality control device using a digital delay circuit.

[Conventional technology]

In order to monitor and eliminate sudden garbled sounds and prohibited words for broadcasting during live broadcasting, a delay device that delays the sound for about 10 seconds or more is required. Conventionally, this delay device has been implemented by using a magnetic tape (tape recorder) by widening the distance between the recording head and the reproducing head. For example, when the tape running speed is 38 cm/sec, an interval of 380 cm is required to delay the tape for 10 seconds. However, in this case, due to the structure of the tape recorder, the device itself becomes large, and the delay amount of the audio signal is fixed.

[Problems to be solved]

The present invention solves the conventional problem that the delay device is structurally large and the amount of delay of the audio signal is fixed. It is meant to be.

[Means for solving problems]

The radio broadcasting quality control device of the present invention includes an A/D and D/A converter for encoding and decoding audio signals, a delay circuit for delaying encoded digital data, and a circuit for monitoring input audio signals. The above-mentioned conventional problems can be solved by adopting a configuration consisting of a monitor circuit, a switch for erasing the audio signal, and a muting circuit equipped with a fade-in/fade-out circuit that erases the digital audio signal using that signal. There is.

〔Example〕

Next, an embodiment of the present invention will be described using FIGS. 1 and 2. As shown in FIG. 1, this radio broadcasting quality control device includes A/D and D/A converters 1 and 5 for encoding audio signals, a delay circuit 2, and a muting circuit 6 for erasing audio. , a switch 1 for erasing audio, and a monitor circuit 23 for monitoring input audio signals. The delay circuit 2 is composed of a digital memory 19, a write address generator 4, and read address generators 9 and 21 for making variable delay possible. The audio cancellation circuit 6 is an up-down counter 3
and a multiplier 7. Input audio signal 11
is a digital value of 12 by A/D converter 1.
and is written to the address 20 designated by the write address circuit 4 of the memory 19. Data is read from the memory 19 from the write address 20 using variable delay data 9.
was generated by subtracting. This is done by address 18 and is input to the muting circuit 6 through signal line 13. This delay circuit 2 has a memory sufficient to obtain an audio delay of at least 10 seconds, and can be varied stepwise from 0 seconds to the maximum delay allowed by the memory capacity by varying the delay data. In the erasing circuit 6, a multiplier 7 adds a coefficient 8 generated from the counter 3 to the input digital data 13.
Calculate and output. Coefficient 8 is a digital value from 0 to 1, and is the ON-OFF value of switch SW1.
controlled by. Output data from the muting circuit 6 is input to the D/A converter 5 through a signal line 14. Furthermore, D/A
The converter 5 decodes the signal to obtain an output audio signal 15. The audio signal is erased by turning on the switch SW1. The operation at this time will be explained with reference to FIG. When the switch SW1 is in the OFF state, the signal line 16 is at a high level, the counter 3 is in the UP mode, and the coefficient 8 is held at 1. (Switch SW1 ON state period in Figure 2).
At this time, when the switch SW1 is turned on, the switch connection 16 becomes low level, the counter switches to the down mode, and the coefficient 8 decreases from 1 to 0 in units of 22 clocks, and is held at 0 (as shown in Fig. 2). period). This change in coefficient causes the output audio signal 15 to fade out. If you continue to press switch SW1 as it is, the audio will remain deleted (during the period shown in Figure 2). Furthermore, when switch SW1 is turned OFF, the signal line 16 is turned off again.
becomes high level, the counter 3 switches to UP mode, and the coefficient changes from 0 to 1 by the clock 22 and is held at 1. This change in coefficient causes the output audio signal 15 to fade in (as shown in period 1 in FIG. 2). With this device, a monitor can listen to the input audio signal 11 through the speaker 10, and can erase the audio being broadcast without clicking by installing the switch SW1.

〔Effect of the invention〕

As explained above, the radio broadcasting quality control device of the present invention has an A/
A D and D/A converter, a delay circuit for delaying encoded digital data, a monitor circuit for monitoring an input audio signal, a switch for erasing the audio signal, and a digital audio signal using the signal. Since it is configured with a muting circuit equipped with fade-in and fade-out circuits for erasing, it is possible to judge whether or not it can be broadcast by monitoring the input audio signal with a monitor circuit, and erase it by using an audio switch that is inappropriate for broadcasting. In addition to being able to be made smaller than before, it also has the advantage of being able to cope with changes in delay time and not causing clicks.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the output signal state when the switch is turned on and off. 1...A/D converter, 2...delay circuit, 5...
D/A converter, 6... Muting circuit, 1
1...Input audio signal, 23...Monitor circuit, SW1...
Switch.

Claims (1)

[Claims] 1. A/D and D/A converters for encoding and decoding audio signals, a delay circuit for delaying encoded digital data, a monitor circuit for monitoring input audio signals, and for erasing audio. A radio broadcasting quality control device consisting of a switch and a muting circuit equipped with a fade-in/fade-out circuit that erases a digital audio signal using the switch.