JPH0529520Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) The present invention relates to a time axis conversion device used as a pitch controller for musical tones, and more specifically, to a time axis conversion device using a charge transfer element.

(Prior Art) Conventionally, pitch control in so-called karaoke where accompaniment sounds are played back using a magnetic playback device has been carried out by varying the running speed of the magnetic tape, and it has not been easy to control each pitch independently. In particular, so-called karaoke using a video disc playback device requires the use of an expensive pitch controller, and the signal is converted into PCM for processing, making it very expensive.

(Purpose of the invention) The present invention has been made in view of the above, and an object thereof is to provide a time axis conversion device that can be easily constructed using a charge transfer device.

(Example of idea) The present invention will be explained below using examples.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

1 and 2 are bucket brigade devices (hereinafter referred to as BBD elements) having the same number of stages.

The input signal passes through a bandpass filter 3 that removes unnecessary frequency components, passes through analog switches 4 and 5 that are alternately controlled to be closed, and then is sent to the BBD elements 1 and 5.
The output signals from the BBD elements 1 and 2 pass through analog switches 6 and 7, which are alternately controlled to be closed, to eliminate the noise of the BBD elements 1 and 2.
The output terminal is passed through a bandpass filter 8 that removes clock components and extracts only the required frequency band.
Output to OUT.

The output of the bandpass filter 8 is passed through analog switches 9 and 10 which are alternately controlled to be closed.
It is supplied to BBD elements 1 and 2 respectively.

On the other hand, the clock pulse oscillators 20 and 21
This is a clock pulse oscillator that outputs charge transfer clock pulses for the BBD elements 1 and 2. The clock pulse frequency of the clock pulse oscillator 20 is fixed, and the clock pulse frequency of the clock pulse oscillator 21 is varied by a variable resistor 21a. Note that the clock pulses output as transfer pulses from the clock pulse oscillators 20 and 21 are two-phase pulses, but are shown in a simplified manner in the figure.

The clock pulse output of the clock pulse oscillator 20 is transmitted through an analog switch 24, and the clock pulse of the clock pulse oscillator 21 is transmitted through an analog switch 26 which is alternately closed with the analog switch 24.
The charge transfer clock pulse is supplied to the BBD element 1 via the clock pulse oscillator 20.
The clock pulse output of the clock pulse oscillator 21 is transferred to the BBD element 2 via the analog switch 25 which is alternately closed with the analog switch 24, and the clock pulse output of the clock pulse oscillator 21 is transferred to the BBD element 2 via the analog switch 27 which is alternately closed with the analog switch 24. It is supplied as a clock pulse. On the other hand, the output of the first phase of the clock pulse of the clock pulse oscillator is supplied to, for example, a ripple counter 22 and frequency-divided, and the half period of the divided output is determined by the number of stages and the output clock pulse frequency of the clock pulse oscillator 20. The value is set to be equal to the delay time of . With this frequency divided output, analog switches 4, 7, 10, 24, 2
7 is closed, and the frequency-divided output A is inverted by the inverter 23 and the analog switches 5, 6, 9, 2 are inverted.
5 and 26 are closed.

In one embodiment of the present invention configured as described above, during a period when the divided output of the counter 22, that is, the output A is at a high potential, the analog switches 4, 7, 10, 2
4 and 27 are closed, analog switches 5,
6, 9, 25 and 26 are controlled to be in a cut-off state. As a result, the output clock pulse of the clock pulse oscillator 20 is supplied to the BBD element 1 as a charge transfer pulse, and the output clock pulse of the clock pulse oscillator 21 is supplied to the BBD element 2 as a charge transfer pulse.

First, to explain the BBD element 1, an input signal is input to the BBD element 1 via the bandpass filter 3, sampled according to the output clock pulse of the clock pulse oscillator 20, and charges corresponding to the sampled values are sequentially transferred. Ru. At this time, since the analog switch 6 is in a cut-off state, the output of the BBD element 1 does not appear at the output terminal OUT. Next, explaining the BBD element 2, since the analog switch 5 is in the cutoff state and the analog switch 7 is in the closed state, the input signal from the input terminal IN is not input to the BBD element 2, and the BBD element 2 Charges corresponding to the input signals accumulated and stored in the circuit are sequentially transferred in accordance with the output clock pulses of the clock pulse oscillator 21, and are outputted to the output terminal OUT via the bandpass filter 8. In addition, since the analog switch 10 is in the closed state, the output signal output to the output terminal OUT is transmitted to the BBD element 2.
is input.

Immediately after the output A becomes a high potential, the charge charged in the first stage of the BBD element 1 is transferred to the clock pulse oscillator 2.
BBD is transferred by an output clock pulse of 0.
When the terminal end of element 1 is reached, the output A becomes a low potential and the output becomes a high potential. So I mentioned above
It acts as if BBD element 1 and BBD element 2 were exchanged. In other words, the input signal from the input terminal IN is not input to the BBD element 1, and the charge corresponding to the input signal accumulated and stored in the BBD element 1 is sequentially transferred in accordance with the output clock pulse of the clock pulse oscillator 21, and the band It is output to the output terminal OUT via the pass filter 8. Further, the output signal output to the output terminal OUT is input to the BBD element 1. The input signal supplied to the input terminal IN is inputted to the BBD element 2 via the bandpass filter 3, and sampled according to the clock pulse oscillator 20, and charges corresponding to the sampled values are sequentially transferred. At this time, analog switch 7
is in the cut-off state, so the output of BBD element 2 is the output terminal
It does not appear in OUT.

Immediately after the output becomes high potential, the charge charged in the first stage of the BBD element 2 is transferred by the output clock pulse of the clock pulse oscillator 20.
When reaching the terminal end of BBD element 2, the output becomes a low potential and acts as if BBD elements 1 and 2 have been exchanged again.

Therefore, the input signal is sent to the clock pulse oscillator 20.
The time axis is compressed or expanded in accordance with the difference between the output clock pulse frequency of the clock pulse oscillator 21 and the clock pulse frequency of the clock pulse oscillator 21.

Also, even when the time axis is compressed, the output signal of the output terminal OUT is
BBD to be returned to BBD elements 1 and 2 via
Elements 1 and 2 are never empty.

Therefore, the time axis can be expanded by setting the variable resistor 21a, and when used as a pitch controller for musical tones, the pitch of musical tones can be controlled by the variable resistor 21a.

Further, the same effect can be obtained even if other charge transfer elements such as CCD elements are used in place of the BBD elements 1 and 2.

(Effects of the invention) As explained above, according to the invention, a charge transfer element is used, and a transfer clock to the charge transfer element when reading an input signal and a transfer clock when reading charge from the charge transfer element are transferred. On the other hand, since the latter transfer clock is made variable, it is possible to compand the time axis, and there is no need to process the signal by converting it into PCM, so the configuration can be simple and inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. 1 and 2...BBD element, 3 and 8...band pass filter, 4-7, 9, 10, 24-2
7...Analog switch, 20 and 21...Clock pulse oscillator, 22...Counter, 23...
...Inverter.

Claims (1)

[Scope of utility model registration request] first and second charge transfer devices having the same number of stages, a first clock pulse oscillator with a fixed frequency, a second clock pulse oscillator with a variable frequency, and dividing and frequency-dividing the output clock pulse of the first clock pulse oscillator. a frequency divider whose half period of the output is set equal to the delay time of the first and second charge transfer devices when reading the input; and an output of the first clock pulse oscillator during which the output of the frequency divider is of one polarity. supplying the clock pulse and the input signal to the first charge transfer device, supplying the output clock pulse of the second clock pulse oscillator to the second charge transfer device, and guiding the output of the second charge transfer device to the output terminal side; supplying the output clock pulse of the first clock pulse oscillator and the input signal to the second charge transfer device while the output of the frequency dividing means is of the other polarity; switching means for supplying the output clock pulse of the first charge transfer device to the first charge transfer device, guiding the output of the first charge transfer device to the output terminal side, and supplying the output to the first charge transfer device. Time axis conversion device.