GB2225147A

GB2225147A - Electronic still camera

Info

Publication number: GB2225147A
Application number: GB8922188A
Authority: GB
Inventors: Nobuya Sakai
Original assignee: Asahi Kogaku Kogyo Co Ltd
Current assignee: Pentax Corp
Priority date: 1988-10-04
Filing date: 1989-10-03
Publication date: 1990-05-23
Anticipated expiration: 2009-10-03
Also published as: GB2225147B; JPH0297183A; FR2637436A1; DE3933186A1; GB8922188D0; DE3933186C2

Description

2225147 ELECTRONIC STILL CAMERA

Background of the Invention

1. Field of the Invention

The present invention relates to an electronic still camera having a playback function of picture and sound signals, and more precisely it relates to an electronic still camera which can distinguishably indicate the picture signal and the sound signal during recording and playback.

2. Description of Related Art

In a recent electronic still camera available on the market, an image of an object formed by a photographic lens is converted to an electric picture signal to be recorded on a magnetic disc as a recording medium. There is also known an electronic still camera in which a sound signal which is input through a microphone can be recorded and played-back, independently of or together with the picture signal.

A magnetic disc which is used in an electronic still camera usually has a format of fifty tracks, so that a picture signal for one field can be recorded on one track of the magnetic disc. The sound signal is recorded on the tracks for the picture signal. Accordingly, some tracks have picture signals recorded thereon and some tracks have sound signals recorded thereon.

In a conventional electronic still camera, when a signal recorded on a track is reproduced (played-back), an operator (user) can not identify the kind of signals, i.e. whether the signal recorded on the track is a picture signal or a sound signal, whether the picture signal t is recorded solely or together with the sound signal, or whether Llhe sound signal is recorded solely or together with the picture signaii. ten feels it inconvenient.

A user Oft For instance, when playing back a sound signal, even if a picture signal is recorded together with the sound signal, the user may miss a chance to see the picture.

Furthermore, supposing that when, for example, ten pictures are taken together with sound signals, a photographer (user) fails to record the sound signals only for the third picture, when the third picture is first played-back. a picture appears without sound. In this case, he or she may misunderstand that the machine has a trouble with the playback function.

The primary object of the present invention is to eliminate the above-mentioned drawbacks by providing a electronic still video apparatus in which whether sound and picture signals are recorded independently or together can be distinguishably indicated during playback of the sound and picture signals.

Summary of the Invention

To achieve the object mentioned above, according to the present invention, there is provided a still video apparatus having a playback means of picture and sound signals recorded on a recording medium, comprising a signal judging means for deciphering a control code signal which is recorded together with the picture signal or the sound signal. or the control code signals which are recorded together withe respective the picture signal and the sound signal to detect whether only the sound signal is recorded, only the picture signal is recorded or both the picture signal and the sound signal are recorded, during the playback of the picture signal or the sound signal, and an indicating means for making an indication corresponding to the deciphered code signal..

With this arrangement, when the recording medium is played-back, three kinds of 01 the record of only the picture signal, (2) the record 30 of only the sound signal, and 03 the record of both the sound and -3picture signals are indicated, so that a user can easily identify the kind of the recorded signals during the playback.

According to another aspect of the present invention, there is provided an electronic still camera having a playback means of picture and sound signals recorded on a recording medium, comprising a control signal recording means for recording control signals which discriminate the states of record when the picture signal is solely recorded, when the sound signal is solely recorded and when the sound and picture signals are recorded together, upon recording the sound and picture signals, a signal judging means for discriminating the control signals recorded together with the sound and picture signals, upon playback of the sound signal and/or the picture signal, and an indicating means for indicating the states of record deciphered by the signal judging means.

With this construction, since the control signals (discriminating signals) are recorded when a picture and/or a sound are or is recorded, and since the states of record can be indicated when the sound signal or picture signal is played-back, a user can easily identify the state of record.

Brief Description of the Drawings

The invention will be described below in detail with reference to the accompanying drawings, in which:

Figure 1 is a block diagram of an indication drive control circuit of an LCD panel for a sound signal in an electronic still camera according to the present invention; Fig. 2 is a perspective view of an electronic still camera according to the present invention; Fig. 3 is a schematic view of a sound track on a magnetic disc for an electronic still camera shown in Fig. 2; Fig. 4 is a diagram of a sound signal and con-Wol code recorded on a magnetic disc shown in Fig. 2; and, Figs. 5, 6 and 7 are schematic views of different indications of an LCD panel for a sound signal in an electronic still camera according to the present invention.

Detailed Description of Preferred Embodiments

Figure 2 shows a perspective view of an electronic still camera according to the present invention. In Fig. 2, the camera has a camera body 10, and a sound adapter 12 as a sound inputting means which is detachably attached to the camera body 1. The sound adapter 12 which is useless when only a picture can be taken without sound is mounted to the camera body 10 when the sound is recorded or the recorded sound is play- backed.

On the rear face of the camera body 10 are provided an LCD panel 14 which indicates record/playback mode, record/playback track number etc. , and a group of switches including up-switch 16A and down-switch 16B for selecting the tracks which are to be tracked by a magnetic head 36 (Fig. 1) provided in the camera body 10 and for commanding the outward or inward movement of the magnetic head 36 by one track and a mode changing switch 16D for changing the mode between a record mode and a playback mode. A release switch 16C and a cover 18 which is opened when a magnetic disc 15 is inserted are provided on the upper surface of the camera body 10.

Female connector 20, positioning holes 22 and 24, and threaded hole 26 are provided on one side face of the camera body 10. The female connector 20 can be connected to a male connector 21 of a sound adapter 12. When the female and male connectors 20 and 21 are interconnected, the data (signals) are transmitted between the sound adapter 12 and the camera body 10 and the power is supplied from the camera body 110 ha,,-ing a power source (not shown) to the soun adapter 12.

The positioning holes 22 and 24 are engaged by associated projections (not shown) provided on the sound adapter 12 when the sound adapter 12 is connected to the camera body 10. The threaded hole 26 can be engaged by a screw (not shown) integral with a locking knob 28 provided on the sound adapter 12. When the locking knob 28 is rotated, the sound adapter 12 is connected to and disconnected from the camera body 10. Note that the camera body 10 has a photographic lens and an image sensors as photographing means, and a finder optical system or other necessary optical means of the camera, although those are not shown.

The sound adapter 12 has a microphone 30, a recording switch 32A for outputting the signals of the commencement and the end of recording, a transfer switch 32B for outputting a command for recording the sound signals which are temporarily stored in a sound memory 40 (Fig. 1) provided in the sound adapter 12 onto the magnetic disc 15 in the camera body 10, and a time mode changing switch 32C (time mode changing means) for changing the period of time in which the continuous recording can be effected, and an LCD panel 34 in which the time mode, recording time, playback time and the kind of signals recorded on the magnetic disc 15 are indicated.

Fig. 3 shows a sound track of the magnetic disc 15 which is loaded in the camera body 10. The sound signals are recorded on the tracks (unit thereof is one track) by the operation of the recording switch 32B in accordance with a predetermined format of the magnetic disc 15. The sound signals are successively recorded on four divided sectors which are spaced from one another at a predetermined distance (space).

The magnetic disc 15 rotates by one turn at about 1/60 second.

- disc 15 as Accordingly, the sound signals are recorded on the magnet-;.

an FM modulated signals which are temporally compresse-4. In the -6illustrated embodiment, the camera has two time modes of 10 second mode and 20 second mode in which the recording is effected for 10 second and 20 second, pespectively. The selection of the time modes can be effected by the time mode changing switch 32C.

The picture signal for one picture plane is recorded on every tracks in accordance with a predetermined format of the magnetic disc 15. In case of a field recording, the picture signal is recorded on one track and in case of a frame recording, the picture signal is recorded on two tracks.

Upon recording, the control codes corresponding to the kinds of the signals are recorded. For instance, when the sound signals are recorded, the corresponding control code concerning the time mode etc. is simultaneously recorded. Similarly, when the picture signals are recorded, the corresponding control code concerning the field recording or the frame recording etc. is simultaneously recorded. When the sound signals are recorded together with the picture signals, the corresponding control code is simultaneously recorded.

Fig. 1 shows a block diagram of a indication control circuit of the LCD panel 34 provided on the sound adapter 12. The sound adapter 12 in the illustrated embodiment is controlled by a system controller 50 provided in the camera body 10.

The sound memory 40 is stored as a digital sound signal which is temporally compressed, so that the stored digital sound signal is output at a normal speed or is temporally extended to be output. The sound memory 40 is connected to a record and playback circuit portion 41 and a sound record and playback circuit 42, as a signal processing circuit.

The record and playback circuit portion 41 converts an analogue -al signal to sound signal outputted from the microphone 30 to a digit output the same to the sound memory 40 when the record starting sw-;1.c1h 32A is actuated to commence the recording, and converts the digital sound signal which is temporally extended and outputted from the sound memory 40 to an analogue sound signal to drive a speaker 35 upon playback.

The sound record and playback circuit 42 converts the digital signal of the sound which is temporarily stored in the sound memory 40 to an analogue signal when the recording switch 32B is operated upon recording. Upon playback, the sound record and playback circuit 42 takes the FM modulated signal of sound recorded on the magnetic disc 15 out through the magnetic head 36 to modulate and convert the same to a digital signal which is then outputted to the sound memory 40.

Upon recording the sound signal onto the magnetic disc 15 through the sound record and playback circuit 42, a start flag and a control code are recorded before the sound signal for every sector, and an end flag is recorded after the sound signal, respectively, as can be seen in Fig. 4. Similarly, upon recording the picture signal, the start flag, the control code, the picture signal and the end flag are recorded.

The timing control portion 43 is connected to the sound memory 40 and the record and plaback circuit portion 41 to synchronize the transmission of the sound signal therebetween. Upon playback, by the timing control circuit 43, the digital sound signal from the sound memory 40 is temporally extended to be outputted to the record and playback circuit portion 41. On the contrary, upon recording, the digital sound signal from the record and playback circuit portion 41 is successively temporally compressed to be stored in the sound memory 40. The timing control portion 43 and the control portion 50 constitute a compresion means and extension means for compressing and extending the time axis of the sound signal.

The arithmetic portion of the amount of the record which w.--'l be referred to as a record amount operating circuit 44 operates the -8temporal amount of sound signal outputted to the sound memory 40 from the sound record and playback circuit 42, based on the capacity needed for the memory, i.e. the addresses needed to memorize the sound signal.

Similarly, the arithmetic portion of the amount of playback which will be referred to as a playback amount operating circuit 45 detects the lapse time of playback, based on the addresses of the sound signal read by the sound memory 40.

Furthermore, the sound memory 40 is connected to a system controller 50 which generally controls the whole operation of the electronic still camera. The system controller 50 is usually comprised of a microcomputer including the record amount operating circuit 44, the playback amount operating circuit 45 and a control code deciphering portion 47.

The tracking control of the magnetic head 36 on the magnetic disc 15 can be effected by the tracking control portion 46 in accordance with the command outputted from the system controller 50.

The magnetic head 36 is connected to the control code deciphering portion 47 as a signal judging means. The control code deciphering portion 47 deciphers the control code recorded on the magnetic disc 15 to discriminate the sound signal and the picture signal. It is also possible to discriminate the sound signal and the picture signal by detecting the presence or absence of a vertical synchronous signal which is included only in the picture signal.

Between the magnetic head 36 and the sound record and playback circuit 42 is provided a switching circuit 48 which selectively connects the magnetic head 36 to the sound record and playback circuit 42 or to the picture record and playback circuit 51. The switching operation is effected in accordance with the control code deciphered by the control code deciphering portion 47 upon playback. Namely. the control code outputted from the magnetic head 36 is deciphered by the control code deciphering portion 47, so that when the sound signal is detected, the magnetic head 36 is connected to the sound record and playback circuit 42, and when the picture signal is detected, the magnetic head 36 is connected to the picture record and playback circuit 51, respectively. On the other hand, upon recording, the control is effected in accordance with the operation of the release switch 16C and the recording switch 32B.

The record amount operating circuit 44, the playback amount operating circuit 45 and the control code deciphering portion 47 are connected to the LCD panel 34 in which the respective indicating elements are controlled, as will be described hereinafter.

The system controller 50 is connected to the switches HA-16D of the camera body 10 and the switches 32A -32C of the sound adapter 12. Note that these switches are generally designated at 49 in Fig. 1. The system controller 50 operates in response to the input of the switches 49 to perform the various controls and arithmetic operations. The system controller 50 controls the rotation of a spindle motor 52 of the magnetic disc 15 through a driver 53 connected thereto thereby to control the rotation of the magnetic disc 15.

The display of the LCD panel 34 is shown in Figs. 5 to 7.

The LCD panel 34 has an indication portion including letters and marks made of a large number of liquid crystal segments. The uppermost letter indicating portion "REC" designates the record mode, the letter indicating portion "PLAY" adjacent thereto designates the playback mode. In the illustrated embodiment, the black letters mean that they are lightened. Namely, in Figs. 5 -7, the mode is being in the playback mode.

The white letter indicating portions AUDIO" and "VIDEO" below the "REC PLAY" designate the sound signal and the picture signal.

respectively. Namely, Fig. 5 shows that only tihe sound signal is -10 recorded, since the letters "AUDIO" appears in the black background. On the contrary, Fig. 6 shows that both the picture signal and the sound signal are recorded, and Fig. 7 shows that only the picture signal is recorded.

The letter indicating portion "1020 SEC/TRACK" located below the sound and picture indicating portion "AUDIO VIDEO" designates the period of time for recording the sound signal on one track of the magnetic disc. In the illustrated embodiment, the camera has two time modes of 10 second and 20 second, as mentioned before. "10" designates JL0 the 10 second mode and "20" the 20 second mode, respectively.

The lowermost indicating portion made of ten bar code segments designates the amount (time) of recorded sound. Upon recording, the bar code segments are successively lightened from the leftmost bar code segment to the righter segments in the lapse of time, so that a user can easily learn how much time is spended on recording. Upon playback, the bar code segments are successively lightened from the leftmost bar code segment to the righter segments in the lapse of time. Figs. 5 and 6 show that the recording is effected for 10 second at the 10 second mode, since the ten bar code segments are all lightened.

The indication of EC", "PLAY", "AUDIO", VIDEO", "10" and "20" are controlled by the control code deciphering portion 47, so that the lightening of the bar code segments is controlled by the record amount operating circuit 44 and the playback amount operating circuit 45.

The electronic still camera according to the present invention operates as follows.

At the sound mode, i.e. when the sound is solely recorded, the sound adapter 12 is mounted to the camera body 10, and the recording switch 32A is manually actuated. When the recording switch 32A is made ON, the recording operation starts to write the sound! signal onto the sound memory 40. When a user's finger is released from the reccrding switch 32A, the recording operation stops. The user actuates the transfer switch 32b to record the sound signal written in the sound memory 40 onto the magnetic disc 15. As a result, the sound signal is outputted from the sound memory 40 to the camera body 10, so that the sound signal is written on the predetermined track of the magnetic disc 15 by the magnetic head 36. The control code is also recorded upon writing the sound signal, as mentioned before.

At the simultaneous record mode, i. e. when both the sound signal and the picture signal are recorded, the operation is as follows. It should be born in mind that the simultaneous record mode includes, for example when the picture is taken in the course of record of the sound, when sound is recorded during the operation of the timer at the self- timer photographing mode, or when the record of the sound is commenced immediately after the completion of the photographing operation or in a predetermined time after the completion of the photographing operation. At the simultaneous record mode, the mode selection switch 16D of the camera body 10 is first actuated to select the desired simultaneous record mode. After that, the release button 16C is pushed down, so that the recording of the sound and the picture are commenced. Upon recording the sound and the picture, the corresponding control code is recorded, as mentioned above.

Upon playback, the mode selection switch 16D is actuated to select the playback mode. After that, the release button 16C is pushed down, so that the spindle motor 52 rotates to rotate the magnetic disc 15 thereby to move the magnetic head 36 on a desired track in order to commence the read the signals. Upon reading the signals, the control code is first deciphered by the control code deciphering portion to detect whether the signal is the sound signal or the picture signal. In case of the picture signal, the record mode is judged, and in case of the sound signal, the time mode is judged. Also, a sin,,,,-'-e mode (onl_, .- T12picture signal or sound signal or a multiple mode (both the picture signal and the sound signal) is judged. For instance, if the sound signal is recorded together with the picture signal at the 10 second mode, the indicating portions "PLAY", "AUDIO VIDET and "10" of the LCD 5 panel 34 are made ON (lightened).

Whether only one of or both of the picture signal and the sound signal is or are recorded on the track of the magnetic disc 15 which is being played-back is indicated as follows.

When the control code fetched by the magnetic head 36 from the magnetic disc 15 is only for the sound signal at the 10 second mode, the control code deciphering portion 47 detects only the control code corresponding to that sound signal. As a result, the control code deciphering portion 47 causes the LCD panel 34 to indicate "AUDIT and "10", in accordance with the detected control code, as shown in Fig. 5.

Furthermore. the record amount operating circuit 44 detects the recording time of the sound signal and causes the LG panel 34 to indicate the corresponding bar code.

If the signal fetched by the magnetic head 36 from the magnetic disc 15 is the signal recorded at the simultaneous record mode including the picture signal and the sound signal at 10 second mode, the control code deciphering portion 47 detects two kinds of control codes corresponding to the sound signal and the picture signal. As a result, the control code deciphering portion 471 causes the LG panel 34 to indicate "AUDIT, "VIDEO" and "10", in accordance with the detected control code, as shown in Fig. 6. Furthermore, the record amount operating circuit 44 detects the recording time of the sound signal and causes the LCD panel 34 to indicate the corresponding bar code.

If the control code fetched by the magnetic head 136 from the magnetic disc 15 is the picture signal recorded at the picture 30 recording mode, the control code deciphering portion 47 de-,ects onli- z -13the control code corresponding to that picture signal. As a result. the control code deciphering portion 47 causes the LCD panel 34 to indicate MDET, in accordance with the detected control code, as shown in Fig. 7.

As can be seen from the above discussion, since the LCD panel 34 indicates whether the signal recorded on the track which is being played- back is the sound signal, the picture signal or the sound and picture signal, a user can easily identify the kind of the signal during playback.

Although the LCD is used as the indicating element in the illustrated embodiment, a light emitter, such as LED can be used in place thereof. Furthermore, the shape and the pattern of arrangement of the indicating portions of the LCD panel 34 are not limited to those in the illustrated embodiment.

It is possible to make the sound adapter 12 integral with the is camera body 10. In this alternative, the LCD panel 14 of the camera body 10 can be formed integral with the LCD panel 34 for the sound indication.

Although the above discussion has been directed to an electronic still camera having recording and playback functions, the invention can be applied to a still video camera having only a playback function without a recording function.

As can be understood from the foregoing, according to the present invention, since three kinds of indications showing that only the picture signal is recorded, only the sound signal is recorded and both the picture and sound signals are recorded can be viewed by a user (photographer), the user can easily identify the kind of signal which is being played-back. Also, according to the present invention, during playback of the sound signal, whether the sound signal is recorded solely or together with the picture signal can be easily recognized.

Claims

CLAIMS:

1. A still video apparatus having a playback function of picture and sound signals recorded on a recording medium, comprising a signal judging means for deciphering a control code signal which is recorded together with the picture signal or the sound signal, or the control code signals which are recorded together withe respective the picture signal and the sound signal to detect whether only the sound signal is recorded, only the picture signal is recorded or both the picture signal and the sound signal are recorded during the playback of the picture signal or the sound signal, and an indicating means for indicating the states corresponding to the deciphered code signal.

2. A still video apparatus according to claim 1, wherein the signal recorded on the recording medium includes three kinds of signals of only the picture signal, only the sound signal and both the picture and sound signals, so that different control code signals corresponding to the kind of the recorded signals are recorded on the decording medium.

3. A still video apparatus according to claim 2, wherein said control code signals are recorded upon recording of the associated three kinds of signals.

4. A still video apparatus according to claim 1, wherein said signal judging means detects whether the sound signal is recorded solely or together with the picture signal or whether the picture signal is recorded solely or together with the sound signal, based on the ocntorol code signals recorded on the recording medium upon recording the picture signal and sound signal, when the sound signal or the picture signal is played-back.

5. A still video apparatus according to claim 1, wherein said indicating means comprises a sound indicating portion for indicating 1 the sound signal, and a picture- 1 IREcating portion for indicating the picture signal.

6. A still video apparatus according to claim 5, wherein said sound indicating portion and said picture indicating portion are actuated when the signal judging means detects that the sound signal is recorded solely and that the picture signal is recorded solely, respectively.

7. A still video apparatus according to claim 6, wherein both the sound indicating portion and the picture indicating portion are lightened when the signal judging means detects that the sound signal and the picture signal are recorded together.

8. A still video apparatus according to claim 1, further comprising reading means for reading the signals of the recording medium, picture signal playback means for playing-back the picture signal read by the reading means, sound signal playback means for playing- back the sound signal read by the reading means, and switching means for selectively connecting the reading means to the picture signal playback means or sound signal playback means.

9. A still video apparatus according to claim 8, wherein said switching means switches the connection in accordance with the output of the signal judging means.

10. A still video apparatus according to claim 9, wherein said signal judging means discriminates the picture signal by detecting said the control code signal. 25

11. An electronic still video apparatus according to claim 10 wherein said the control code signal is a vertical synchronous signal contained the picture signal.

12. A still video apparatus according to claim 8, wherein said recording medium is a magnetic disc. 30

13. A still video apparatus according to claim 12, wherein said -16reading means is is a magnetic disc is a magnetic head.

14. In an electronic still camera having a picture signal recording means for recording a picture signal outputted from a picture taking means onto a recording medium and a sound signal recording means for recording a sound signal outputted from a sound inputting means onto the recording medium, the improvement comprising means for recording control codes for discriminating whether the sound signal and/or the picture signal are recorded solely or together upon recording the associated signals.

15. An electronic still camera according to claim 14, wherein said recording medium is a magnetic disc, so that the sound signal, the picture signal and the control codes can be recorded on the magnetic disc by a same magnetic head.

16. In an electronic still camera having picture recording means for recording a picture signal outputted from a picture taking means onto a recording medium, a sound recording means for recording a sound signal outputted from a sound inputting means onto the recording medium, a playback means of the picture signal recorded on the recording medium, a playback means of the sound signal recorded on the recording medium, the improvement comprising a control signal recording means for recording control signals which discriminate the states of record when the picture signal is solely recorded, when the sound signal is solely recorded and when the sound and picture signals are recorded together, upon recording the associated sound and picture signals, a signal judging means for discriminating the control signals recorded together with respective the sound signal and the picture signal, upon playback of the sound signal and/or the picture signal, and an indicating means for indicating the states of record deciphered by the signal judging means.

17. An electronic still camera according to claim ILE, wherein z 1 11 said indicating means comprises a sound indicating portion for indicating the sound signal, and a picture indicating portion for indicating the picture signal, and wherein said sound indicating portion and said picture indicating portion are actuated when the signal judging means detects that the sound signal is recorded solely and that the picture signal is recorded solely, respectively.

18. An electronic still camera according to claim 17, wherein both the sound indicating portion and the picture indicating portion are actuated when the signal judging means detects that the sound signal and the picture signal are recorded together.

19. An electronic still camera according to claim 17, further comprising reading means for reading the signals of the recording medium, picture signal playback means for playing-back the picture signal read by the reading means, sound signal playback means for playing-back the sound signal read by the reading means, and switching means for selectively connecting the reading means to the picture signal playback means or sound signal playback means.

20. An electronic still camera according to claim 19, wherein said switching means switches the connection in accordance with the output of the signal judging means.

21. A still video apparatus according to claim 20, wherein said signal judging means discriminates the picture signal by detecting said the control code signal.

22. An electronic still camera according to claim 491, wherein said the control code signal is a vertical synchronous signal contained the picture signal.

23. An electronic still camera according to claim 21. further comprising a sound adapter which can be detachably connected to a camera body.

24. An electronic still camera according to claim 2'vl, wherein the 19 sound inputting means, the sound playback means and the indicating means are provided in the sound adapter.

25. An electronic still camera according to claim 24, wherein the indicating means indicates in accordance with the signals deciphered by 5 the signal judging means.

26. In an electronic still camera having a picture taking means, a picture recording means for recording the picture signal outputted from the picture taking means onto a recording medium, a sound recording means for recording a sound signal outputted from a sound inputting means onto the recording medium, a playback means of the picture signal recorded on the recording medium, a playback means of the sound signal recorded on the recording medium, the improvement comprising a control signal recording means for recording control signals which discriminate three modes including a picture recording mode in which the picture signal is solely recorded, a sound recording medium in which the sound signal is solely recorded and a simultaneous record mode in which the sound signal and the picture signal are recorded together, when the sound signal and/or the picture signal are recorded, a signal judging means for deciphering the modes, based on the control signals upon playback of the sound signal and the picture signal, and an indicating means for indicating the states corresponding to the modes deciphered by the signal judging means.

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