Abstract:
A device for adjusting audio and video signals includes two rotary encoders, one for plural audio adjusting circuits which are arranged to adjust audio signals and the other for plural video adjusting circuits which are arranged to adjust video signals. The rotary encoders are arranged to selectively actuate the plural audio adjusting circuits and the plural video adjusting circuits respectively. The arrangement not only simplifies the operation of the device but also reduces the number of necessary parts.

Description:
This is a continuation application under 37 CFR 1.62 of prior application Ser. No. 08/146,453 filed on Nov. 1, 1993 (abandoned) which is a continuation of Ser. No. 07/780,870 filed on Oct. 18, 1991 (abandoned). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a signal adjusting device and more particularly to a device for making adjustment relative to video and audio signals. 
     2. Description of the Related Art 
     The conventional apparatuses for recording and reproducing video signals on and from a magnetic tape (hereinafter referred to as VTRs) have input adjusting devices arranged in most cases to adjust video signals, such as a luminance signal, chrominance signals, and also the audio signal levels of individual channels. Some of the VTRs have been arranged to permit adjustment of all these signals with a single adjustment knob. The arrangement to adjust the signals by using adjustment knobs discretely arranged for respective different signals and channels increases the number of parts and thus requires a larger space. The arrangement to adjust the audio signal levels and video signals with a single adjustment knob makes operation very difficult for the operator and thus has presented a problem in respect of the operability of the apparatus. 
     SUMMARY OF THE INVENTION 
     This invention is directed to the solution of the above-stated problems. It is therefore an object of the invention to provide an adjusting apparatus which is arranged to permit not only reduction in the number of parts but also improvement in operability of the apparatus. 
     An adjusting apparatus which is arranged as an embodiment of this invention comprises of a plurality of audio adjusting means for making adjustment relative to audio signals respectively; a plurality of video adjusting means for making adjustment relative to video signals respectively; a first rotary encoder used for the audio signals; a second rotary encoder used for the video signals; first selecting means for selectively actuating the plurality of audio adjusting means according to an operation of the first rotary encoder; and second selecting means for selectively actuating the plurality of video adjusting means according to an operation of the second rotary encoder. 
     The above and other objects and features of the invention will become apparent from the following detailed description of an embodiment thereof taken in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram showing the arrangement of a video signal recording and reproducing apparatus which is arranged as an embodiment of this invention. 
     FIG. 2 shows the arrangement of the operation panel of the apparatus shown in FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following describes an embodiment of this invention in detail with reference to the drawings: 
     FIG. 1 shows the arrangement of a video signal recording and reproducing apparatus (VTR). FIG. 2 shows the front panel of the apparatus shown in FIG. 1. 
     Referring to FIGS. 1 and 2, a control part group 1 which is arranged to control the component parts of the body of the VTR includes a mechanism control part 1m, a video control part 1v, a servo control part 1s and a system control part 2. The system control part 2 is the central part of the control part group 1 and is arranged to control the flow of data between microcomputers. An input device 5 includes a rotary encoder 6 for audio level adjustment, a rotary encoder 7 for video signal adjustment and a switch group 8. The switch group 8 includes selection buttons 8c which are provided for selection of an audio channel to be adjusted by the rotary encoder 6, and function buttons 8d which are arranged to permit switching the functions and purposes thereof from one over to another by means of software according to the state of the VTR and the mode of the panel. 
     A panel control part 3 serves as an interface between the user and the machine and is arranged to convert an input signal from the input device 5 into a control signal for the VTR body and to send the control signal to the system control part 2. The VTR is provided with a display part 4. These control parts are electrically interconnected for input and output of signals between them. 
     Since the level of the audio signal is frequently adjusted, a mechanism for audio level adjustment must excel in operability. In the case of this embodiment, the selection buttons 8c are provided for selection of audio channels. The level of any desired audio channel can be adjusted by using one of the buttons 8c in conjunction with the rotary encoder 6 which is provided for that purpose. 
     Meanwhile, the video signals of varied kinds which will be described later are not frequently adjusted in general. In the case of this embodiment, the subject of adjustment is selected with one of the function buttons 8d. The video signal is then adjusted by the rotary encoder 7 only with respect to the subject matter thus selected. 
     The details of the flows of the video and audio signals and the matters to be adjusted by the rotary encoders 6 and 7 are as described below: 
     A luminance signal Y and two color-difference signals Pb and Pr are inputted to input terminals 10Y, 10b and 10r, respectively. These signals Y, Pb and Pr are supplied to a video signal recording processing circuit 11. The circuit 11 then performs various processes to make the signals Y, Pb and Pr into a signal form suited for recording. The signals thus processed are supplied to amplifiers 12Y, 12b and 12r. The signals Y, Pb and Pr outputted from the amplifiers 12Y, 12b and 12r are mixed together by a mixer 13. The output signal of the mixer 13 is supplied to a recording and reproducing part 20 via a recording amplifier 14 to be recorded on a magnetic tape together with audio signals by means of a known rotary head. 
     Audio signal input terminals 15a, 15b, 15c and 15d are arranged for respective different audio signal channels to supply audio signals CHa, CHb, CHc and CHd of these channels to a level adjustment circuit 16. The levels of these audio signals are adjusted by the level adjustment circuit 16. After the level adjustment, these audio signals are supplied to an audio signal recording processing circuit 17 to be converted into a signal form suited for magnetic recording. The signals of four channels outputted from the audio signal recording processing circuit 17 are supplied respectively to the recording and reproducing part 20 to be recorded on the magnetic tape along with the above-stated video signal. 
     Next, the operation to be performed on the reproducing side of the VTR is described as follows: a video signal which is reproduced by the recording and reproducing part 20 is amplified by a reproduction amplifier 21. The amplified reproduced video signal is supplied to a separation circuit 22 to be separated into signals Y, Pb and Pr. The levels of these reproduced signals Y, Pb and Pr are then individually adjusted by amplifiers 23Y, 23b and 23r. With their levels thus adjusted by the amplifiers 23Y, 23b and 23r, the signals Y, Pb and Pr are brought back into their original signal form by a video signal reproduction processing circuit 24 and are then outputted from output terminals 25Y, 25b and 25r to the outside, respectively. 
     The audio signals of four channels are reproduced by the recording and reproducing part 20. These audio signals are brought back into the original signal form by an audio signal reproduction processing circuit 26. After that, these audio signals are supplied to a level adjustment circuit 27 to have their levels adjusted there. The level-adjusted audio signals are outputted from output terminals 28a, 28b, 28c and 28d as four-channel audio signals CHa, CHb, CHc and CHd. 
     The system control part 2 is arranged to output an audio adjustment signal A in response to the selection of the selection buttons 8c and the operation of the audio rotary encoder 6. The audio adjustment signal A includes a recording-side level adjustment signal a1 for individually adjusting the levels of the audio signals of different channels on the recording side and a reproduction-side level adjustment signal a2 for individually adjusting the levels of the audio signals of different channels on the reproduction side. 
     The signal a1 is supplied to the level adjustment circuit 16 to adjust the input levels of the audio signals CHa, CHb, CHc and CHd of the different channels. The other signal a2 is supplied to the level adjustment circuit 27 to adjust the output levels of the audio signals CHa, CHb, CHc and CHd of the different channels. The selection buttons 8c mentioned in the foregoing are arranged to designate and select a level adjusting channel and also to designate either the input signal or the output signal as a level adjusting audio signal. The level of the audio signal thus designated is adjusted by the operation of the rotary encoder 6. 
     The video control part 1v is arranged to output a video adjustment signal V in response to the operation of the video rotary encoder 7 and that of the function buttons 8d. The video adjustment signal V includes adjustment signals v1, v2, v3, v4, v5 and v6. These signals v1 to v6 are arranged to be inputted to the video signal recording processing circuit 11, the amplifiers 12Y, 12b, and 12r, the recording amplifier 14, the reproduction amplifier 21, the amplifiers 23Y, 23b, 23r and the video signal reproduction processing circuit 24, respectively. 
     At each of the video signal recording processing circuit 11 and the video signal reproduction processing circuit 24, the delay time of a delay circuit which is arranged to control the timing of the color-difference signals Pb and Pr relative to the luminance signal Y and also the delay time of a delay circuit, which is arranged to control the timing of these signals relative to an external reference signal, are adjusted in accordance with the adjustment signal v1 or v6. 
     At the amplifiers 12Y, 12b and 12r and the amplifiers 23Y, 23b and 23r, the levels of the luminance signal Y and the color-difference signals Pb and Pr are individually controlled in accordance with the adjustment signals v2 and v5. Further, at the recording amplifier 14 and the reproduction amplifier 21, an equalizing process, signal levels, a recording current, etc., are adjusted in accordance with the adjustment signals v3 and v4. 
     In the embodiment described, the rotary encoder 6 is arranged to be used only for audio level adjustment which is expected to be frequently made. As for the video signals which require diverse adjustment actions on them, the rotary encoder 7 is singly arranged to be usable for all these adjustment actions. This arrangement not only greatly relieves the operator from the burden of operation but also does not require many parts. Besides, the audio and video rotary encoders are separately arranged while the selection buttons 8c for audio signal adjustment and the function buttons 8d are also separately arranged. The arrangement is very clear to the operator, so that the embodiment is easily operable.