GB2124056A - Video tape recorder - Google Patents

Abstract

A video tape recorder includes a character generating and inserting circuit for inserting desired character information - eg date of recording - into a video signal so that the character information may be displayed on the screen of a CRT superposingly with the picture. In one form, an output from an AFC circuit is used an one sync signal for displaying the inserted character. In another form, a second vertical sync signal is produced from the original vertical sync signal in synchronism with the composite sync signal, which is supplied to a horizontal display position control circuit, in displaying the inserted charactor on the screen of a CRT. Further, there is provided a character generating and inserting circuit which includes a battery-powered clock generator thereby allowing to superimpose information as to the date and time of recording on a picture to be recorded. Still further, a video recording system having a detachably mountable RF adapter is provided. Another feature of the present invention reside in a unique display structure capable of indicating a selected mode of operation using a liquid crystal display. Also provided is a device capable of displaying the current operating position of the tape in a cassette once loaded.

Description

SPECIFICATION Video tape recorder BACKGROUND OF THE INVENTION 1. Field of the Invention This invention generally relates to apparatus for temporarily storing video signals fed from either a video camera or a radio wave receiver and supplying the stored video signals to a radio wave transmitter or directly to a television set for replay, and, in particular to a video recorder for temporarily storing such video signals on a magnetic recording medium such as magnetic tape.

2. Background of the Invention Video tape recoders are well known in the art, and they are widely used not only in the field of television broadcasting business but also at home lately. Home video recorders have become quite popular over the last decade; however, since historically video recorders have been developed predominantly as one of broadcasting equipment, there are various areas which need to be developed in order that video tape recorders are to be more widely used at home.

One of such areas which need to be improved is the insertion of character information, such as date of recording, into a video signal. In particular, in the case of home-use VTRs (Video Tape Recorders), it is true that some video cameras are equipped with a circuit for generating and inserting character information, such as date of recording and title of program, and such character information may be recorded on a recording medium simultaneously with video signals. However, such a system is useless when it is desired to record character information as combined with video signals transmitted in the form of television radio waves. That is, in order to have character information inserted into video signals processed from received television radio waves, it is necessary that a character generating and inserting circuit be provided in a VTR itself, but such a VTR has not yet been proposed.However, a care must be exercised in inserting desired character information, such as date of recording, into video signals before recording in a VTR, which have been transmitted in the form of television radio waves. A simple addition of a character generating and inserting circuit to a VTR system would bring about various disadvantages such as instability of inserted characters when displayed, or production of the so-called "jitter", depending upon the intensity of received radio waves and noises.

There are several other areas which need to be improved for VTRs to be more widely used, particularly at home, as will be understood as one progresses in reading the present specification.

SUMMARY OF THE INVENTION In accordance with the present invention, several improvements are provided in VTRs.

In one aspect, there is provided a character generating and inserting circuit for generating desired character information, such as date of recording, and inserting the same into video signals before being recorded on a recording medium. In the preferred form, the character generating and inserting circuit of the present invention uses a part of VCO (Voltage-Controlled Oscillator) output of AFC (Automatic Frequency Control) provided in a VTR as a horizontal driving signal. In another aspect, there is provided a system for correcting the vertical position of characters displayed on a CRT screen as fed from a character generating and inserting circuit provided in a VTR. In a further aspect, there is provided a system for inserting desired character information, such as date of recording, into video signals simply by powering up a VTR.Furthermore, there is also provided a character inserting system in which desired character information, particularly date of recording, may be automatically inserted into video signals without requiring manual operation of switches.

A VTR has several modes of operation such as "RECORD", "PLAY" and "REWIND", and the present invention provides a novel and simple system for indicating the current mode of operation. This system uses a plurality of liquid crystal display elements arranged in a particular manner and the LCD elements are selectively activated in accordance with the selected mode of operation. The present invention also provides an improved VTR system in which a RF adapter is so provided that it may be connected to and disconnected from either of VTR and tuner timer. Such a structure allows to provide a VTR small in size, light in weight and thus low in cost. Moreover, in a still further aspect of the present invention, there is provided a device for storing the information as to use amount of magnetic tape for recording thereon video signals.This aspect of the present invention is particularly useful when applied to a VTR using a magnetic tape cassette which may be loaded into or unloaded from a VTR main body. Because, when a magnetic tape cassette provided with such a device is loaded into a VTR, the current position or the end of the last use of the tape may be indicated at once.

Therefore, a primary object of the present invention is to improve video recorders.

Another object of the present invention is to provide a character generating and inserting circuit which may be advantageously used in a video recorder.

A further object of the present invention is to provide an improved system for inserting desired character information into video sig nals.

A still further object of the present invention is to improve the quality of characters displayed on a CRT screen.

A still further object of the present invention is to provide a VTR system convenient in use, small in size, light in weight and low in cost.

Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram showing the overall structure of a VTR system including a character generating and inserting circuit in accordance with one aspect of the present invention; Figures 2A and 2B are waveform diagrams showing typical examples of video signals; Figure 3 is a schematic illustration showing a CRT screen; Figure 4 is a block diagram showing one example of circuit for detecting position P at T, and T2 in x-y coordinates as shown in Fig.

3; Figure 5 is a schematic illustration showing partly in blocks the relation between a character generating and inserting circuit of the present invention and a television set displaying an example of characters on its screen; Figure 6 is a block diagram showing the structure of one example of the character generating and inserting circuit; Figure 7 is a block diagram showing one example of video color signal processing circuit suitable for extracting a horizontal driving signal for use in a character generating and inserting circuit of the present invention; Figure 8 is a block diagram showing the structure of a character generating and inserting circuit constructed in accordance with one embodiment of the present invention; Figure 9 is a schematic illustration showing vertical shift in position of a character displayed on a CRT screen;; Figure 10 is a time chart showing the relation between the composite and vertical synchronization signals supplied to a vertical display position control circuit; Figure 11 is a block diagram including a character generating and inserting circuit as provided in the luminance signal processing system of VTR in accordance with the present invention; Figure 12 is a block diagram showing a circuit for producing a new vertical synchronization signal which is to be used in controlling the display position of characters in accordance with the present invention; Figure 13 is a time chart which is useful for explaining the operation of the circuit shown in Fig. 12;; Figure 14 is a block diagram showing another embodiment of character generating and inserting circuit constructed in accordance with the present invention Figure 15 is a block diagram showing a further embodiment of character generating and inserting circuit constructed in accordance with the present invention; Figure 16 is a time chart useful for explaining the operation of the circuit shown in Fig.

15; Figure 1 7 is a schematic illustration showing the front panel of a VTR having a system for indicating the mode of operation constructed in accordance with one embodiment of the present invention; Figure 18 is a block diagram showing a control circuit of the system shown in Fig. 17; Figures 19 (a) through (k) are schematic illustrations showing individual predetermined patterns representing corresponding modes of operation of VTR; Figures 20 and 21 are block diagrams illustrating typical modes of use of a VTR system;; Figures 22A-22C show one embodiment of the present VTR system, wherein Fig. 22A is a perspective view showing a RF adapter constructed in accordance with the present invention, Fig. 22B is a perspective view showing a part of VTR on which the RF adapter of Fig. 22A may be detachably mounted and Fig. 22C is a perspective view showing a part of tuner timer on which the RF adapter of Fig. 22A may also be detachably mounted; Figures 23 and 24 are block diagrams showing typical modes of use of the RF adapter in accordance with the present invention; Figure 25 is a partially cross-sectional view illustrating the condition when the present RF adapter is mounted on a VTR; Figure 26 is a partially cross-sectional view illustrating the condition when the present RF adapter is mounted on a tuner timer; ; Figure 27 is a perspective view showing a VTR magnetic tape cassette having additional magnetic tape adhered to one exterior side edge thereof for storing information as to use amount of the tape housed therein; Figure 28 is a schematic illustration showing a device for storing information of use amount of tape for recording thereon video signals on the additional tape provided on the tape cassette of Fig. 27; and Figure 29 is a schematic illustration showing another arrangement of the additional tape for storing use amount information of the tape for storing video signals.

DESCRIPTION OF THE PREFERRED EMBODI MENTS Referring now to Fig. 1, there is shown in block form the overall structure of a video tape recorder (hereinafter also referred to as "VTR") system in which a character generating and inserting circuit is provided in accordance with one embodiment of the present invention. As shown, the VTR system includes a television antenna 1 for receiving video and audio signals as transmitted in the form of radio waves and a tuner 2 to which the signals received by the antenna 1 are supplied. The tuner 2 is connected not only to a video signal processing circuit 3, but also to an audio signal processing circuit 4. The video signal processing circuit 3 includes a luminance signal recording system 3A, a color signal recording system 3B, a tape head system 3C, a luminance signal reproducing system 3D and a color signal reproducing system 3E.On the other hand, the audio signal processing circuit 4 includes an audio signal recording system 4A, a tape head system 4B and an audio signal reproducing system 4C. A character generating and inserting circuit 7 is also provided as connected between the tuner 2 and the video signal processing circuit 3.

Moreover, connected to both of the video and audio processing circuits 3 and 4 is a RF converter 5 which is also connected to a cathode ray tube (CRT") such as a television receiver.

A VRT system is defined by those components provided between the antenna 1 and the TV receiver 6. In the case of so-called home-use VTRs, in order to reduce a recording band, the video signal processing circuit 3 transforms a received video signal to carrier color signal of lower frequencies, which is then recorded on a video track after having been superposed with FM-modulated luminance signal. Similarly, a received audio signal is recorded on an audio track. In reproduction, video and audio signals are read by respective heads and the signals thus read are then supplied to the TV receiver 6 through the RF converter 5 for visual display on the TV screen.

As is well-known in the art, in the case of NTSC ("National Television System Commit tee") system, there are 525 horizontal scanning lines on a TV screen and 60 frames are displayed per second. A video signal used in television transmission is a so-calld composite video signal which includes not only horizontal synchronization ("sync") signals, but also vertical sync signals. Figs. 2A and 2B show typical video signals used in TV transmission, wherein Fig. 2A shows horizontal sync signals HSYNC and Fig. 2B shows vertical sync signals VSYNC. In order to display characters as inserted on a TV screen, it is conceivable to determine the position of inserted characters by counting pulses on the basis of these sync signals.

As shown in Fig. 3, the position of a point P on TV screen may be determined by a vertical distance T1 from the top of the screen and a horizontal distance T2 from the left side of the screen. In determining the position of point P, vertical sync signal VSYNC may be used as a reference for the vertical distance T, and horizontal sync signal HSYNC may be used as a reference for the horizontal distance T2.

Fig. 4 shows in block form a circuit for detecting the distances T1 and T2 for determining the position of point P on the TV screen shown in Fig. 3. As shown, the circuit of Fig. 4 includes a sync signal separating circuit 8A, a vertical sync signal detecting circuit 8B, a horizontal sync signal detecting circuit 8c and a pair of counters 8D and 8E.

The vertical distance T1 measured from the top edge of the TV screen is detected by the first counter 8D, which is thus reset by a vertical sync signal VSYNC and counts horizontal sync signals HSYNC. On the other hand, the horizontal distance T2 measured from the left side edge of the TV screen is detected by the second counter 8E. For this reason, the second counter 8E is reset by a horizontal sync signal HSYNC and counts, for example, a carrier color signal of 3.58 MHZ or input clock signals having other frequencies. As a result, the position of a character to be inserted into the TV screen may be properly determined by using the circuit shown in Fig. 4.

Fig. 5 shows one example of the character generating and inserting circuit 7 as connected to the TV set 6 on the screen of which is displayed desired character, or date in this particular example. As shown, the character generating and inserting circuit 7 includes a sync separating circuit 7A, a character generating circuit 7B and a character inserting circuit 7C. The sync separating circuit 7A receives a video signal and separates horizontal and vertical sync signals from the video signal, and the thus separated sync signals are used to determine the position of desired characters to be displayed on the screen of TV set 6.The character generating circuit 7B is provided as connected to the sync separating circuit 7A and it generates desired character information such as a date, which is then supplied to the character inserting circuit 7C in association with the timing of a signal fed from the sync separator circuit 7A. The character inserting circuit 7C may, for example, be comprised of an analog switch, and it combines the thus supplied character information with a video signal and supplies such a combined signal to the TV set 6. Accordingly, on the screen of TV set 6 is displayed not only a picture defined by the received video signal but also characters inserted by the circuit 7.

In this case, however, in the regions where the intensity of TV radio waves is rather weak and/or TV radio waves tend to include many noises, the horizontal and vertical sync signals separated out from the incoming video signal by the sync separator circuit 7A would cause to move characters displayed on the TV screen up and down and/or sidewise rapidly, so that it will be difficult to see displayed characters and tire a viewer. Fig. 6 is a block diagram showing one example of the character generating and inserting circuit of Fig. 5, and like numerals are used to indicate like elements. As set forth previously, the circuit of Fig. 6 includes an analog switch 7D as an example of the character inserting circuit 7C.

As shown, vertical sync and composite signals, VSYNC and CSYNC, respectively, are supplied from the sync separator circuit 7A to the character generating circuit 7B. With such a structure, however, if noises are contained in sync signals, the trigger level at the character generating circuit 7B will fluctuate, which will then produce jitter to inserted characters when displayed on the TV screen.

In accordance with one aspect of the present invention, in view of the fact that the video color signal processing circuit of a VTR system employs an AFC (Automatic Frequency Control) circuit, the character generating and inserting circuit is so structured that a part of VCO (Voltage-Controlled Oscillator) output from AFC is utilized as a horizontal driving signal of the character generating circuit. In order to facilitate understanding this aspect of the present invention, the video color signal processing circuit provided in a VTR system will be briefly described hereinbelow.

In the case of azimuth recording normally used in home-use VTRs, cross-talk between adjacent tracks cannot be neglected. For this reason, color signal processing utilizing line correlation is normally adopted. Fig. 7 shows in block form one example of video color signal processing circuit suitable for use in extracting a horizontal driving signal to be used in the present character generating and inserting circuit. As shown, the circuit of Fig.

7 includes a 1/2 fH killer 9, a phase compara tor 10, a LPF 11, a VCO 12, a four phase rotor 13, 1/160 frequency divider 14 and 1/4 frequency divider 15. It is to be noted that "HD" indicates a horizontal driving signal, "f," frequency of horizontal sync signal and "RHP" rotating head pulse.

In the case of phase shift method of VHS system, for each horizontal scan period, recording is carried out by rotating the phase of low-pass transformation color signal by 90 and by reversing the direction of rotation between adjacent tracks. In the structure of Fig. 7, the 90" phase rotation is carried out by the four phase rotor 13 and the control of direction of rotation between adjacent tracks is carried out by using rotating head pulses RHP.

The composite signal CSYNC extracted by the sync separator circuit 7A is fed into the 1/2 fH filler to eliminate equalizing pulses thereby forming a horizontal driving signal HD. The thus formed horizontal driving signal HD on one hand is supplied to the four phase rotor 13 which causes the low-pass transformation color signal to be phase-rotated for each horizontal scan period. On the other hand, the signal HD is also supplied to the phase comparator 10 in which phase comparison is made against an output signal from the 1/160 frequency divider 14. The phase comparator 10 supplies a detected error voltage through LPF 11 to VCO 12 having central frequency of 160 fH thereby controlling the output oscillating frequency of VCO 12.Then, the output from VCO 12 is on one hand supplied to the 1/4 frequency divider 15 to be converted into low-pass transformation color signal frequency, which, in turn, is supplied to the four phase rotor 13. On the other hand, the output form VCO 12 is also supplied to the 1/160 frequency divider 14 to be divided into 1/160 in frequency to produce horizontal sync signalfrequency fH, which is then inputted to the phase comparator 14.

As a result, the video color signal processing circuit of Fig. 7 allows to obtain a horizontal driving signal HD as supplied as an output from the 1/160 frequency divider 14. In this manner, the video color processing circuit includes an AFC circuit which produces a lowpass transformation color signal whose phase is fixed at the horizontal sync signal frequency fH of recording signal. As is obvious for those skilled in the art, such as AFC circuit is commonly used in a TV set.

As pointed out before, the present character generating and inserting circuit is structured in combination with such an AFC circuit provided in the video color signal processing circuit of VTR system such that a part of VCO output from the AFC circuit is utilized as a horizontal driving signal to be supplied to the character generating circuit of present character generating and inserting circuit.

Fig. 8 shows in block form the structure of one embodiment of the present character generating and inserting circuit for use in a VTR system, and, as shown, the overall structure is similar to that of Fig. 6 so that like numerals are used to indicate like elements. In the structure shown in Fig. 8, an AFC circuit 7E is provided as connected between the sync separator circuit 7A and the character generating circuit 7B. Of importance, such an AFC circuit 7E does not need to be provided additionally because the video color signal processing circuit of a VTR system normally includes an AFC circuit as shown in Fig. 7 and it may be used for the purpose of the present invention.

In this manner, in accordance with the present invention, as a horizontal driving signal to be supplied to the character generating circuit 7B, use is made of a VCO output from the AFC circuit 7E instead of direct application of composite signal CSYNC so that, even in the regions of weaker TV radio waves and/or abundance in noises, characters inserted into the TV screen may be refrained from jittering as much as possible when displayed.

Now, description will be made as to another aspect of the present invention directed to prevent characters displayed as inserted on a TV screen from moving up and down and/or right and left rapidly. Fig. 9 illustrates the case in which a character indicated by a double line forming a rectangle moves up and down when displayed as inserted on a TV screen. As mentioned previously, an inserted character moves up and down in a vibrating manner when displayed, for example, if sync signals separated from a video signal for use in determining the position in a TV screen for displaying the inserted character contains a significant amount of noises in the case where the position of inserted character to be displayed on the TV screen is determined by vertical and horizontal display position control circuits provided in the character generating and inserting circuit.Because, in such a structure, vertical sync signal VSYNC is used as a reset signal of the vertical display position control circuit which is comprised of such elements as a counter and which receives composite signal CSYNC as a clock signal.

Fig. 10 illustrates the waveform of each of composite and vertical sync signals, CSYNC and VSYNC, respectively, and the relation therebetween. Composite signal CSYNC contains vertical sync signals and equalizing pulses provided at the front and rear of each vertical sync signal as well as horizontal sync signals.

For this reason, if composite and/orounter fails tc count properly. As a result, the position for fluctuate due, for example, to noise in TV radio waves, a pulse indicated by Q might fail to be counted or an interior counter fails to count properly. As a result, the position for displaying an inserted character becomes unstable thereby causing the displayed character to be vibrated in the vertical direction.

With the foregoing premise, the present invention has been made based on the fact that the horizontal display position control circuit is not in use during horizontal retrace period, and, thus, in accordance with the present invention, provision is made of means for generating a new vertical sync signal in synchronism with composite signal CSYNC utilizing an output from the horizontal display position control circuit whereby the thus generated new vertical sync signal is used to reset the internal counter of the vertical position control circuit.

Fig. 11 shows in block form the luminance signal processing circuit of a VTR provided with the character generating and inserting circuit 7 constructed in accordance with the present invention. As shown, the circuit of Fig. 11 includes recording components 16A-16H which are LPF 16A, AGC 16B, preemphasis 1 6C, white clip/dark clip 1 6D, clamp 16E, FM modulator 16F, HPF 16G and amplifier 1 6H. The circuit of Fig. 11 also includes a video head 17 having a rotating transformer 1 7A and magnetic tape 18. The circuit of Fig. 11 further includes reproducing components 1 9A-1 9J which are preamplifiers 1 9A and 19B, switcher 1 9C, HPF 1 9D, DOC 19E, limiter 19F, FM demodulator 19G, deemphasis 19H, LPF 191 and amplifier 19J.

A video signal supplied to the circuit of Fig.

11 is combined with character information inserted by the character generating and inserting circuit 7 and such a combined signal is then supplied to LPF 1 6A, where a carrier color signal component is removed and a luminance signal component is extracted and supplied as an output. At LPF 1 6A, audio carrier wave of 4.5 MHz and high frequency noises are also cancelled. Next at AGC 1 6B, the signal is delayed approximately by 1 micro second in order to match timing between the luminance and carrier color signals. And, at the same time, adjustment is carried out so as to allow to obtain an optimum input level to the FM modulator 1 6F. Such a leveladjusted signal is then emphasized at high frequency region by the preemphasis 1 6C and supplied to the white clip/dark clip 1 6D, where overshoot and undershoot components are removed.Thereafter, the leading end of sync signal is arranged straight by the clamp 1 6E and FM-modulated by the FM modulator 1 6F. Then, at the HPF 1 6G, that portion of low frequency band of the thus FM-modulated signal which overlaps with the band of lowpass transformation carrier color signal is removed, and an output from HPF 1 6G is supplied to the recording amplifier 16H.

The video signal adjusted to an optimum level by the recording amplifier 1 6H is then supplied to the video recording head 17 so that information is recorded on the magnetic tape 18. In this manner, recording of a video signal obtained from TV radio waves and inserted with desired character information is carried out.

In reproduction, reading of the tape 1 8 is carried out by a pair of heads 17 alternately and video signals thus obtained are supplied to respective preamps 1 9A and 1 9B through the rotating transformer to be amplified and the thus amplified signals are combined by the switcher 1 9C thereby forming a continuous video signal. This video signal is then supplied to HPF 1 9D where low frequency transformation color signal components of 1 MHz or lower are removed to produce an FM luminance signal, which is then supplied to DOC 1 9E to correct noticeable dropouts.

And the thus corrected luminance signal is then supplied through the limiter 1 9F, which determines the detecting level of dropout, to the FM demodulator 1 9G. After demodulation, the luminance signal is deemphasized by the deemphasis 1 9H thereby being restored to the original state before the high frequency boost, and an output from the deemphasis 1 9H is inputted to LPF 191 where the remain ing FM components are removed. Finally, the video signal outputted from LPF 191 is amplified to a predetermined level by the output amplifier 19J to be supplied as an output video signal.

The character display correcting system of the present invention is so structured to prevent the characters inserted by the character generating and inserting circuit 7 provided in a VTR system from moving up and down rapidly when displayed on a TV screen. Fig.

12 shows in block form one embodiment of the means for generating a new vertical sync signal to be used in putting into practice the present character display correcting system.

As shown, the system of Fig. 12 includes a horizontal display position control circuit 20, comprising a counter 20A, retriggerable monostable multivibrators 21 and 22, an inverter 23 and an OR gate 24. In Fig. 12, "New VSYNCS indicates a new vertical sync signal which is in synchronism with a composite signal. Of importance, the primary objective of the circuit of Fig. 12 is to generate a new vertical sync signal "New VSYNC" in synchronism with a composite signal CSYNC using an output from the horizontal display position control circuit 20 utilizing the fact that the horizontal display position control circuit 20 is not in use during vertical retrace or flyback period.

Fig. 13 illustrates a time chart which is useful for explaining the operation of the circuit shown in Fig. 1 2. It should be noted that the nomenclature used for each waveform corresponds to that shown in Fig. 12. As already explained previously, the composite signal CSYNC contains vertical sync and equalizing pulses. And, the vertical sync signal VSYNC falls at the equalizing pulse following the vertical sync pulse of composite signal CsyNc.

The position of such a falling end fluctuates as affected by noises or the like.

In accordance with this aspect of the present invention, with the use of the structure shown in Fig. 12, instead of the vertical sync signal VSYNC a new vertical sync signal New VSYNC in synchronism with the composite signal CSYNC is generated, and the thus generated new vertical sync signal New VSYNC is used to control the vertical display position of inserted characters. Described more in detail, the vertical sync signal VSYNC is applied to the retriggerable mono-multi 21 to cause its output Q to be high in level. Then, an output from the counter 20A of the horizontal display position control circuit 20 to which the composite signal CSYNC is inputted is applied to retrigger the mono-multi 21.In this case, the unstable time period of mono-multi 21 is set at a value in between the equalizing and horizontal sync pulses, e.g., 45 micro seconds.

With such a structure, even if the vertical sync signal VSYNC terminates, the mono-multi 21 may operate in response to an output from the counter 20A which corresponds to the equalizing pulses of composite signal CSYNC, and output Q returns to low level upon termination of the equalizing pulse period. As a result, output Q of the mono-multi 21 varies as indicated by the waveform designated by New VSYNC which is in synchronism with composite signal CSYNC. If it is so structured that the counter of a vertical display position control circuit (not shown) is reset by such a new vertical sync signal New VSYNC, count error can be prevented from occurring completely.The other retriggerable mono-multi 22 is provided to control the operation of the counter 20A of the horizontal display position control circuit 20 such that the counter 20A does not count the vertical sync pulses of composite signal CSYNC which is inputted during the time period in which the vertical sync signal VSYNC is high.

It should be understood that the circuit shown in Fig. 12 is just one example for generating a new vertical sync signal New Vsync and there are other alternatives as obvious for those skilled in the art.

A further aspect of the present invention will now be described. This aspect of the present invention is concerned with the structure for inserting desired characters as displayed on the screen of TV set, and, in particular, there is provided a character inserting system which allows to insert desired characters, such as date and time of recording, into the screen of TV set as necessary as long as a power supply of VTR is turned on.

In order to attain such objective, in accordance with this aspect of the present invention, a character generating and inserting circuit is provided in a VTR and a batterypowered clock generator employing a quartz oscillator and the like is additionally provided in the character generating and inserting circuit. Such a clock generator may be used to display date and/or time on the TV screen as inserted information.

Fig. 14 shows one embodiment of the present character generating and inserting circuit of a VTR system which includes a batterypowered clock generator. In the structure shown in Fig. 14, those components indicated by 31-38 define the character generating and inserting circuit 7, wherein the numeral 31 indicates a clock generator, 32 a counter, 33 a numeral converter, 34 a display device such as LCD (Liquid Crystal Display), 35 a timer circuit, 36 a sync separator circuit, 37 a numeral generating circuit, 38 a character inserting circuit and 39 a VTR main body power supply. The structure shown in Fig. 14 also includes a battery E, a switch SW1 for selecting eigher an output signal from a video camera or a TV signal, another switch SW2 for switching between insertion and non-insertion of character and a further switch SW3 for powering up or down the VTR.

Those components indicated by 31 through 35 shown as arranged side-by-side in the top row constitutes a clock section which is maintained in operation at all times as powered by the battery E as long as the battery E is alive.

Clock pulses produced by the clock generator 31 controlled by a quartz oscillator and the like are counted by the counter 32, and its count is then supplied to the numeral converter 33, for example, of the type which carries out seven segment numeral conversion. The thus converted signal is then supplied to the display device 34 comprised, for example, of liquid crystal display elements. From the viewpoint of insertion of characters to be displayed on a TV screen, it is not necessary to provide the display device 34, but it is rather advantageous to provide such a display device because it may be used as a clock.This particular display device shown in Fig. 14 indicates that year, month and day may be displayed, but the mode of display should not be limited only to this and various other possibilities exist, for example a combination of day, hour and minute or year, month, day, hour and minute. It may also be so structured that the mode of display may be selected switchingly.

The timer circuit 35 is not always necessary for the purpose of this aspect of the present invention; however, it is preferred to be provided because, when provided, the power supply switch SW3 may be turned on automatically to set the VTR operative at a desired time. Thus, it should be so structured that the timer circuit 35 is also powered by the battery E, if provided. As an alternative structure, the timer circuit 35 may be intergrated into the counter 32. In this case, the counter 32 has a function of timer. Such a clock section may be formed as a combination of CMOS (Complementary Metal Oxide Semiconductor) IC and LCD elements, and, when so formed, the battery E may ordinarily last two to three years.

In order to insert desired characters such as date and/or time into a TV screen there is provided a synchronization separating circuit 36 which separates out a sync signal from the video signal inputted thereto. Using such a separated sync signal as a reference, a numeral generating circuit 37 generates a video signal which is numerically same as that displayed on the display device 34. For this reason, it is structured such that an output from the numeral converter 33 is also supplied to the numeral generating circuit 37.

The video signal having a numeric pattern generated by the numeral generating circuit 37 is then supplied to a character inserting circuit 38 where the numeric video signal is combined with another video signal supplied from a video camera or TV radio waves. The switch SW2 is, for example, turned on so as to carry out such a combination. As understood, the circuits 36, 37 and 38 are all powered by the VTR main body power supply 39.

With the above-described structure, the clock section defined by components 31-35 remains operative irrespective of the on/off condition of the VTR power supply 39. Accordingly, it is not necessary to set the date or time each time when the VTR is used. Besides, desired characters such as date or time of recording may be combined with a video signal supplied either from a video camera or TV radio waves.

Fig.15 shows another embodiment of the character generating and inserting circuit 7 provided with a battery-powered internal clock section for use with a VTR system 40 provided as connected between the TV antenna 1 and the CRT 6 such as a TV set. As shown, the embodiment of Fig. 15 is structurally similar to that of Fig. 14 so that like numerals are used to indicate like elements thereby omitting the repetition of description. As compared with the embodiment of Fig.14, additional components are provided in the embodiment of Fig. 15 such as a switching signal generating circuit 41 and an inserting time setting circuit 42 together with ancillary diodes and resistors. Another additionally provided component is a manually operable switch SW4 which is operated to change the kind of characters to be inserted.As will be described later more in detail, such a structure is advantageous because desired characters such as date and/or time of recording can be automatically inserted into picture information when such picture information is recorded in a VTR without requiring manual operation of a switch.

The inserting time setting circuit 42, which determines the time for inserting desired characters by a time period during which a voltage is applied, is connected to the character inserting circuit 38 through a protective diode D1 and directly to the timer circuit 35. The switching signal generating circuit 41, which supplies as its output a signal for switching the kind of characters to be inserted, is connected to the numeral converter 33 through a protective diode D2. Furthermore, the switching signal generating circuit 41 is directly connected to the inserting time setting circuit 42 so as to receive a voltage therefrom. The automatic character insertion with the structure shown in Fig. 15 takes place in the following manner as will be explained with particular reference to Fig. 16.

The timer circuit 35 in which recording start and end time are set constantly receives the numerical pattern regarding time from the numeral converter 33. The timer circuit 35 is also connected to a recording device (not shown) of VTR 40. When the numerical pattern supplied from the numeral converter 33 agrees with the recording start time set in the timer circuit 35, or, the operator initiates a recording operation, the timer circuit 35 sup plies an on signal to the inserting time setting circuit 42 and to the numeral converter 33. In response thereto, the inserting time setting circuit 42 applies a high level signal to the character inserting circuit 38 and to the switching signal generating circuit 41 for a predetermined time period t, for insertion of desired characters.

Upon receipt of the above-mentioned on signal, the numeral converter 33 converts the count of the counter 32 at the time of receipt of the on signal into a character pattern representing the corresponding year, month, day, hour and minute, among which that portion of the numerical pattern representing year, month and day is supplied to the numeral generating circuit 37 to be converted into a video signal containing such information, which is then supplied to the character inserting circuit 38. While receiving the high level signal, the character inserting circuit 38 continues to supply the above-mentioned video signal containing date information, together with another video signal containing picture information to be recorded, to the video signal processing system 3.As a result, during the time period while the high level signal is being applied, the video signal containing date information is combined with the video signal containing picture information and such a combined video signal is then recorded on a video track of a recording medium such as magnetic video tape.

On the other hand, when the above-mentioned high level signal is applied, the switching signal generating circuit 41 supplies a switching signal to the numeral converter 33 after elapsing a predetermined time period t2 as from the point in time when the high level signal has been applied. Upon receipt of this switching signal, the numeral converter 33 now supplies a numerical pattern as to day, hour and minute at the time of receipt of the on signal instead of the pattern of year, month and day to the numeral generating circuit 37. As a result, to the video signal processing system 3 is inputted a video signal containing information as to day, hour and minute instead of year, month and day.

After elapsing a time period t, as from the time when the on signal has been received, the inserting time setting circuit 42 changes the high level signal to a low level signal, so that the character inserting circuit 38 stops to supply the video signal and the switching signal generating circuit 41 supplies a reset signal to the numeral converter 33 thereby resetting the numeral converter 33 to the original condition prior to the application of the on signal. When the numerical pattern supplied from the numeral converter 33 matches the recording end time set in the timer circuit 35, the timer circuit 35 supplies an off signal so that the recording operation is terminated.

As described above, if a TV program has been recorded automatically while being away by setting tt to be 20 seconds and t2 to be 10 seconds with the recording start time being set in the timer circuit 35 as "1 2 o'clock 34 minutes, January 10, 1983", or, alternatively, if a TV program has been recorded as initiated by an operator at the above-mentioned date and time, then, when replayed, at a predetermined position of TV screen is displayed "January 10, 1 983" for the first 10 seconds and then "10, 12 o'clock 34 minutes" for the next following 10 seconds.

Consequently, a viewer can confirm the recording date and time for a predetermined time period at the beginning of replay automatically.

The switching signal generating and inserting time setting circuits 41 and 42, respectively, may be so connected to be powered by the battery E. As shown in Fig. 15, by providing a circuit leading from the positive terminal of battery E to the numeral inserting circuit 38 through the protective resistor R1, depression type switch SW2 and protective diode D3, character insertion can be carried out manually. In other words, while the switch SW 2 is being manually depressed by an operator, current flows from the battery E to the numeral inserting circuit 38 so that a high level signal is applied to the numeral inserting circuit 38 which then supplies a video signal containing such numerical information.On the other hand, in the circuit defined by the positive terminal of battery E, protective resistor R2, depression type switch SW4, protective diode D4 and numeral converter 33, when the switch SW4 is manually turned on momentarily, a switching signal is applied from the battery E to the numeral converter 33 so that the kind of characters to be inserted may be switched at any time.

A still further aspect of the present invention will now be described. This aspect of the present invention relates to a novel technique for indicating the current mode of operation of various devices such as tape and video recorders. In a device such as a VTR, there are various modes of operation, so that it is required to indicate the current or selected mode of operation which is easily noticeable by an operator. It is common practive to provide a plurality of operating buttons comprised of semi-transparent material as arranged in a control panel of VTR with an LED or lamp disposed inside of each of the buttons, whereby depression of a selected button causes the LED or lamp disposed therein to be lit thereby indicating that the corresponding mode of operation has been selected. In this case, however, since light intensity is rather low, it is rather difficult to recognize which of the buttons has been lit particularly in a light place such as outdoors. Further, there are other disadvantages such as difficulty in mounting LEDs or lamps, relatively large power consumption and high in cost.

In accordance with this aspect of the present invention, there is provided a novel method for indicating the current mode of operation of a multimode device such as a VTR, which is easy to judge a selected mode of operation even in a light place, low in cost as well as in power consumption. Briefly stated, the operating mode indicating system of the present invention includes a liquid crystal display having a plurality of pattern segments capable of being individually activated, a plurality of operating buttons each associated with the corresponding mode of operation and control means connected between said plurality of pattern segments and said plurality of operating buttons whereby depression of one of said plurality of operating buttons causes to activate said plurality of pattern segments selectively in a predetermined manner under the control of said control means.

This aspect of the present invention will be described further in detail with reference to Figs. 17 through 19. Fig. 17 schematically illustrates the front panel of a VTR to which this aspect of the present invention is applied.

As shown, a plurality of operating buttons such as "CASSETTE EJECT" 51, "REWIND" 52, "PLAY" 53, "F.F." 54, "RECORD" 55, "DUBBING" 56, "STILL/PAUSE" 57 and "STOP" 58 are provided at the front panel.

An operating mode indicator 59 comprised of liquid crystal display and having a plurality of pattern segments is also provided at the front panel. As shown, the indicator 59 includes pattern segments some triangular and some parallelogramic in shape and these pattern segments are selectively activated depending on the selection of operating buttons 51-58 to form a predetermined pattern corresponding to the selected operating button. Each of the operating buttons 51-58 has a term showing the corresponding mode of operation and a predetermined pattern which is to be formed by the indicator 59 when its button is depressed.

Fig. 18 is a circuit diagram showing the electrical connection between the operating buttons 51-58 and the indicator 59. As shown, there is provided a control circuit 60 including logic gates connected in a predetermined manner as connected between the operating buttons 51-58 and a display driving circuit 62 which in turn is connected to the indicator 59. The control circuit 60 is also connected to various drivers 61 for driving various components of VTR such as motors and magnetic heads. Thus, when one of the buttons 51-58 is depressed, a driving signal is supplied to the corresponding driver from the control circuit 60 and at the same time a display drive signal is supplied to the display driving circuit 62 which in turn supplies high level signals selectively at its output terminals in a predetermined manner. As shown in Fig.

18, the display driving circuit 62 has eight input terminals corresponding to the number of the operating buttons 51-58 and 14 output terminals which are connected to the corresponding pattern segments and which are selectively rendered high in level thereby causing the corresponding pattern segments to be activated.

For example, in response to those modes of operation including PLAY, RECORD, F.F. and REWIND, the output terminals of the display driving circuit 62 are rendered high in level as in the following manner.

Operating Button Output Terminals To Be Activated PLAY and RECORD 1, 2, 4.

F.F. 1, 2, 4, 8, 9, 11.

REWIND 4,6,7,11,13,14.

Under the condition, if the operating button 53 for PLAY is depressed, the output terminals 1, 2 and 4 of the display driving circuit 62 are rendered high in level in response to a signal supplied from the control circuit 60, so that a pattern shown in Fig. 19(b) will be defined in the indicator 59. While, if the button 54 for F.F. is selected, those output terminals 1, 2, 4, 8, 9 and 11 of the circuit 62 are activated thereby defining the pattern of Fig. 19(c) in the indicator 59. Fig. 19 shows various patterns to be defined by the indicator 59 by causing the pattern segments to be activated selectively.

A still further aspect of the present invention relating to improvements in a VTR system will now be described. As described previously, a VTR system, in general, comprises a video camera, a VTR and a tuner timer. As shown in Fig. 20, a VTR normally includes a RF adapter 72 having the function of modulating video and audio signals of VTR 71 to the same frequency as that of TV radio waves in the mode of reproduction and the thus modulated signal is received at the antenna terminal of a TV set to be displayed using an idle channel. The VTR system shown in Fig.

20 includes a video signal processing circuit 73, an audio signal processing circuit 74, a power supply 75 and a control circuit 76 for controlling the supply of power form the power supply to the RF adapter 72. The VTR 71 is provided with a RF output terminal 77 and a tuner timer terminal 78. Also shown in Fig. 20 are a tuner timer 80, an antenna 81, a TV receiver 82 and a turn-over switch 83.

In a VTR system shown in Fig. 20, in order to implement reproduction through the tuner timer 80, the tuner timer 80 must be connected to the output terminal 78 of VTR 71 via cable, and, at the same time, the switch 83 must be operated to have the TV receiver 82 connected to VTR 71. In the case where the tuner timer 80 is not to be used, the RF output terminal 77 of VTR 71 may be directly connected to TV receiver 82 by means of an external turn-over switch 84, as shown in Fig.

2 i. However, in such a VTR system having the V7 R 71 in which the RF adapter is built- in, several disadvantages will be encountered In the first place, in the case of recording using a video camera, the RF adapter 72 is not necessary, and, thus, such a built-in structure is disadvantageous in terms of weight, size and cost. This can be quite important for portable type VTRs.

Second, the output terminal 78 of VTR 71 and the tuner timer 80 are connected via 10 to 20 lead lines, so that if such a connection is to be made by a coaxial cable, a large coaxial cable and a pair of high frequency coaxial connectors are required; whereas, if such a connection is to be made by a composite cable, a special cable containing therein a coaxial cable and exclusive sockets to be used with such a special cable need to be prepared, which could push up the cost. Third, since VTR 71 requires to be provided with the RF output terminal 77 in addition to the tuner timer output terminal 78, a significant area is expended by terminals.

This aspect of the present invention is directed to obviate these problems and to provide a novel VTR system light in weight, small in size and low in cost. Briefly stated, in accordance with this aspect of the present invention, a RF adapter is removed from a VTR thereby forming the RF adapter as an independent unit which may be detachably connected to either of VTR and tuner timer.

Fig. 22A shows a RF adapter 90 constructed as a separate unit independent of a VTR in accordance with the present invention.

The iiF adapter 90 of Fig. 22A includes a signet, input connector 91 which may be detail chably connected to either of a VTR or a tuner timer and a RF output terminal 92. Fig. 22B shows a part of VTR 93 from which the RF adapter has been removed and which is provided with an output connector 94 for outputting video ana audio signals. The output connector 94 is so structured that it may be brought into detachable connection with the input connector 91 of RF adapter 90 and with the connector of a cable from the tuner timer.

With such a structure, when reproduction is to be carried out without using the tuner timer, the RF adapter 90 is mounted on the VTR 93 as shown in riq. is etod ine #F output terminal 92 of RE adapter 9v is connected to the antenna terminal OT iV set 82 through the antenna turn-ower switch 84.On the other hand, in the case OT mounting the Hi adapter 90 on the VTR 93, it IS only necessary to bring the input connector 91 of RF adapter 90 into engagement with the output connector 94 of VTR 93, as shown in Fig. 25.

When reproduction is to be carried out through the tuner timer 95 in the present VTR system, the RF adapter 90 is mounted on the tuner timer 95 as shown in Fig. 24 to establish connection such that video and audio signals supplied from the VTR 93 are modulated by the RF adapter 90 and then supplied to the sI V set 82 via the RS output terminal 92 and the antenna turn-over switch 73 in the tuner timer 95. In the present embodiment, in order that the RF adapter 90 be mounted on the tuner timer 95, the RF adapter 90 is placed in the recess formed in the tuner timer 95, as shown in Fig. 26, whereby the output connector 96 is coupled to the input connector 91 and the RF output terminal 92 is coupled to the connector 97. Moreover, as shown in Fig. 26, a lid may be provided advantageously.In accordance with the present embodiment, there is no need to provide a control circuit (element 76 shown in Figs. 20 and 21) for implementing on/off control of the power supply to the RF adapter.

A stili further aspect of the present invention will now be described. This aspect of the present invention relates to a novel structure for storing and displaying the information as to use amount of a recording medium such as magnetic tape and it is particularly advantageous when applied to cassette tape and video recorders in which a tape cassette may be load into or unloaded from the recorder main body. In accordance with this aspect of the present invention, even if a tape cassette has been unloaded from a recorder with the tape maintained at an arbitrary use position, once the tape cassette is loaded into the recorder again, the use amount of tape in the last preceding operation may be indicated.

This is advantageous because the counter provided in the recorder to indicate the current position of the tape does not need to be inkialized.

One embodiment of this aspect of the present invention when applied to a VTR will be described in detail with reference to Figs.

27-29. Fig. 27 illustrates a tape cassette 101 containing therein a length of magnetic recording tape extending between a supply reel and a take-up reel. In accordance with the present invention, additional magnetic tape 102 for storing information as to use amount of tape is adhered to one side edge of the cassette 101. Fig. 28 is a schematic illustration showing an embodiment of the present device for use with the tape cassette 101 for recording a count vague corresponding to the use amount ot rape in the cassette I 101 on the additional magnetic tape 102 and indicating tne use amount OT tape by reading the count vaiue recorded on the additional magnetic tape 102.

As shown in Fig. 28, the present tape use amount storing device includes a counter 103 whicn detects the number of revolutions of ree cr the running time period as the tape travels to count a value which is proportional to the amount of travel of tape. A display 104 is provided to receive a signal from the counter 103 thereby indicating a numerical value which is proportional to the use amount of tape. Also provided is a pulse converter 105 which converts the signal from the counter 103 into a binary signal when the information of use amount of tape is recorded on the additional magnetic tape 102 during the process of unloading the tape cassette 1 from the main body of recorder.A binary signal converted by the pulse converter 105 is amplified by an amplifier 106 and supplied through a switch 107 to a recording and reproducing head 108 to be recorded on the additional magnetic tape 102. The recording and reproducing head 108 is so structured and disposed to be in contact with or in proximity with the additional magnetic tape 102 when set in position that it records information on the additional magnetic tape 102 when the tape cassette 101 is loaded into the main body and it reads the information recorded on the additional magnetic tape 102 when the tape cassette 101 is unloaded from the main body.

An amplifier 109 is provided for amplifying a signal read by the head 108 during information read-out mode while the tape cassette 101 is being loaded into the main body, and another pulse converter 110 is provided to convert the thus amplified signal into a decimal number, which is then supplied to the counter 103 whereby the counter 103 is set at this value. Also provided is an erase head 111 which is disposed in the rear of the recording and reproducing head 108 with respect to the direction of ejection of tape cassette 101. An erase current source 112 is provided to supply an erase current to the erase head 111 through the switch 107.

In operation, after loading the tape cassette 101 into the main body, such as tape or video recorder, provided with the above-described structure for storing the information as to use amount of tape and initializing the counter 103 to "000", when the main body is set in operation, the value displayed at the display 104 progresses since the counter 103 supplies new data as the tape travels. When the tape is stopped, the counter 103 holds the current count. And, then, as the tape cassette 101 is moved in the eject direction for unloading, the switch 107 is turned to be in contact with recording contacts OUT, whereby the count held in the counter 103 is converted into the corresponding binary data by the pulse converter 105, which data is then supplied to the recording and reproducing head 108 through the amplifier 106 to be recorded on the additional magnetic tape 102.

On the other hand, when the tape cassette 101 having the additional magnetic tape 102 on which the information as to use amount of tape has been recorded is loaded into the main body provided with the above-described structure, the switch 107 is turned to be in contact with reading contacts IN as the cassette 101 moves into the main body whereby a binary data read by the recording and reproducing head 108 from the tape 102 is amplified and restored to a decimal data by the pulse converter 110, which decimal data is then set into the counter 103 and indicated at the display 104. In this event, irrespective of the data indicated at the display 104 prior to the loading of the cassette 101, the information obtained from the tape 102 of the cassette 101 which has just been loaded is set into the counter 103 and displayed at the display 104.At this time, since current is supplied from the erase current source 112 to the erase head 111 through the switch 107, the information recorded on the tape 102 comes to be erased by the erase head 111 after having been read by the recording and reproducing head 108.

Under the condition, when the tape inside of the cassette 101 is caused to advance, the counter 103 counts the amount of advancement of tape and its count is added to the data already set in the counter 103 by reading the information from the tape 102. In this case, if the tape travels in the reverse direction, or the tape is rewound, the value of count is subtracted from the data in the counter 103. In either case,the resulting added or subtracted value is indicated at the display 104. In this manner, when the cassette 101 is unloaded from the main body after advancing the tape inside the cassette 101 over a certain distance, the current value of the counter 103 is recorded on the tape 102 by means of the recording and reproducing head 108. It should be noted that no information is recorded on the tape 102 because old information has already been erased.

In accordance with this embodiment of the present invention, since the count of the counter 103 is recorded on the tape 102 after conversion to a binary data, in the case where the count value is represented by a four digit data, the data may be recorded in the form of a 14 bit signal using various modulation methods. For example, the data may be recorded as a chain of 14 N poles or S poles.

Recording and reproducing operations of such a binary data requires only a recording and reproducing head and amplifiers both simple in structure.

In Fig. 28, the connection of the switch 107 to the erase head 111 may be reversed such that the erase head 111 may be connected to the erase current source 11 2 at the time of unloading the tape cassette 101 from the main body. In this case, however, old information which has already been recorded on the tape 102 is erased when the cassette 101 is unloaded from the main body. It is to be noted that desired objectives may still be obtained even without the erase head 111. In this case, old information is erased when new information is recorded on the tape 102 su perposingly. Further, if provided, the erase head 111 mav be comprised of a permanent magnet, and use may be made of direct current for the erase current source 112.

As a further alternative, it may be so structured that a roller which rotates in contact with a side, top or bottom surface of the cassette 101 as it is loaded into or unloaded from the main body is provided and clock pulses are generated every predetermined angle of rotation as the roller rotates whereby recording and reproducing operations are controlled in synchronism with thus produced clock pulses. Still further, it may be so structured that the roller is driven to rotate by a motor thereby allowing to carry out the loading and unloading operations automatically with clock pulses generated in association with the rotation of the roller. Such a structure is advantageous because recording and reproducing operations may be carried out accurately.

As shown in Fig. 29, the additional magnetic tape 102 may be comprised of an adhesive tape sheet 113 and magnetic tape strips 102' fixed to the sheet 113. This is advantageous because the tape 102 may be easily adhered to any existing tape cassette.

Of course, the tape 102 may be provided as previously adhered to the cassette 101. Instead of magnetic tape, magnetic powder material may be directly fixed to the cassette 101 using an appropriate binder.

While the above provides a full and complete disclosure of the preferred embodiments oi the present invention, various modifications, alternate constructions and equivalents may be employed without departing from the true spirit and scope of the invention. Therefore, the above description and illustration should not be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims (23)

1. A system for inserting a second video signal into a first video signal, at least said first video signal being a composite video signal, comprising: separating means ror receiving said first video signal and suppiying horizontal and ver- tical sync signals as separated from said first video signal; generating means responsive to said horizontal and vertical sync signals supplied from said separating means for generating said second video signal; and insertion control means connected to receive said first and second video signals for controlling the insertion of said second video signal into said first video signal.

2. A system of Claim 1, wherein said separating means includes a first sync separator circuit which receives said first video signal and supplies said vertical sync signal and a composite sync signal and a second sync separator circuit which receives said composite sync signal and supplies said horizontal sync signal.

3. A system of Claim 2, wherein said second sync separator circuit is comprised of an automatic frequency control ("AFC") circuit.

4. A system of Claim 3, wherein said AFC circuit is provided in a video signal processing circuit of a video tape recorder ("VTR").

5. A system of Claim 3, wherein said horizontal sync signal is produced from a part of a voltage-controlled oscillator ("VCO") output of said AFC circuit.

6. A system of Claim 3, wherein said second video signal includes a predetermined character information.

7. A system of Claim 6, wherein said insertion control means includes a switch which is turned on and off to control the insertion of said second video signal into said first video signal.

8. A system of Claim 7, wherein said switch is an analog switch.

9. A display control system for controlling the display of a combined video signal on a CRT screen in a raster scanning format, said combined video signal being formed by inserting a second video signal into a first video signal which is a composite video signal, comprising: separating means for receiving said first video signal and supplying vertical and composite sync signals as separated from said first video signal; generating means for generating said second video signal; means for inserting said second video signal into said first video signal; horizontal display position control means responsive to said composite sync signal for controlling the horizontal display position of said combined video signal; means responsive to said vertical sync signal and to an output of said horizontal display position control means for producing a new vertical sync signal; and vertical display position control means re sponslve to said new vertical sync signal for controlling the vertical display position of said combined video signal.

I v. A system of Claim 9, wherein said composite sync signal includes a horizontal sync signal and a predetermined number of equalizing pulses fore and aft of said horizontal sync signal thereby defining an equalizing period.

1 X . A system of Ciaim , wneleiii said new vertical sync signal remaines at high level longer than the original vertical sync signal.

12. A system for inserting character information into a video signal to be displayed on the screen of a CRT, comprising; first power source; means for constantly producing time and date information as powered by said first power source; a power supply circuit connectable to a second power source; combining means connectable to said power supply circuit for combining said video signal with at least a part of said time and date information.

13. A system of Claim 12 further comprising a timer circuit connected to said means for constantly producing time and date information.

14. A system of Claim 12 further comprising control means for controlling the operation of said combining means such that said combining means is activated in response to the initiation of recording of said video signal for a predetermined time period.

15. A structure for indicating a selected mode of operation of a multi-mode device such as a video tape recorder, comprising: a liquid crystal display having a plurality of pattern segments capable of being activated individually; a plurality of selection buttons each of which is assigned with a particular mode of operation; and control means connected between said plurality of pattern segments and said plurality of selection buttons for controlling the activation of said plurality of pattern segments selectively thereby defining a particular pattern by selected ones of pattern segments corresponding to a selected one of said plurality of selection buttons.

16. A video recorder system of the type in which a video signal is supplied from a video recorder directly or through a tuner timer to a CRT after having been modulated by a RF adapter, wherein improvements reside in that said RF adapter includes a first connector for connection with said CRT and a second connector for connection with said video recorder, said RF adapter being detachably mountable to either one of said video recorder and said tuner timer.

17. A structure for displaying the current operating position of a recording medium contained in a housing when said recording medium is set in position, comprising: means for receiving said recording medium, said recording medium being removable from said means for receiving; an auxiliary recording medium provided on said housing; means for recording information as to the current operating position on said auxiliary recording medium when said recording medium is unloaded from said means for receiving; means for recording the information as to the current operating position of said recording medium from said auxiliary recording medium when said recording medium is loaded into said means for receiving; and means for displaying the current operating position read by said means for reading.

18. A structure of Claim 17, wherein said recording medium is magnetic tape and said housing is a cassette which houses said magnetic tape.

19. A structure of Claim 18, wherein said current operating position is the position of said magnetic tape opposite to a magnetic head which records or reads desired information on or from said magnetic tape.

20. A structure of Claim 17, wherein said auxiliary recording medium includes a magnetic recording material.

21. A video signal processing system substantially as described with reference to the accompanying drawings.

22. A display control system substantially as described with reference to the accompanying drawings.

23. A video recorder system substantially as described with reference to the accompanying drawings.