Digital videocassette recorder from Panasonic

By Alexander Luganskiy

Review contents:

Professional video recording: Its perspectives in Russia Video Cassette Recorders New videocassette recorders ProfessionalDV of The JVC Company Videocassette recorders of D-9 format of The JVC Company Digital videocassette recorder from Panasonic Tape videocassette recorders of DVCAM format High Definition Videocassette Recorder of The Sony Company Sony Videocassette Recorders of D-10 Format (MPEG IMX)

The facilities of recording/reproduction of The Panasonic Company had entered the use of Russian television long ago. The models of S-VHS format became the most popular ones, which allowed to many Russian TV companies to switch to actually professional video production, however some specialists are very skeptic about S-VHS format itself. With such an opinion it is possible to agree, but it is impossible to doubt the fact that Panasonic videocassette recorders represent all functions usual for devices of higher classes to the user. The same is about facilities that operate with digital video formats. The Panasonic Company produces very wide range of equipment. The equipment that entered this review can be divided in few categories:

• DV;
• DVCPRO;
• DVCPRO HD;
• D5;
• HD-D5.

Let’s view techniques entering each one of these categories.

DV equipment

AG-DV1DC videocassette recorder is good for mobile application, as it can be easily situated in palm. The sizes of the device are only about 143×94.5×69.7 mm, and weight is 500 g. In spite of that this device if equipped with color LCD display of 3.5" size, on which except for image the information about temporary code and time left till the end of tape on the cassette is traced. The maximal recording time on the cassette of miniDV is 83 min. VCR is equipped with generator and facility of reading of temporary code. AG-DV1DC is equipped with IEEE 1394 interface and entries/outputs Y/C and composite (by video). As to sound, there is analogous linear input/output and microphone input. There is an opportunity of recording of two PCM sound channels. Except for that the cutoff point for connection of remote control facilities is provided. Power voltage is 7.2…7.9 V, consumed power is 4.5 W. The power of videocassette recorder can be done from accumulator battery of from stationary mains through adapter. Volume of the battery delivered in the set is 800 mAh.

DVCPRO equipment

This category includes more wide range of videocassette recorders assigned for solution of practical tasks of video production.

AJ-D455 VTR

AJ-D455 videocassette recorder is the representative of the new generation of studio videocassette recorders of DVCPRO format. It is equipped with entries/outputs of digital sound (AES/EBU) and provides and opportunity of setting of SDI or IEEE 1394 interface modules. The recording and reproduction can be done in DVCPRO and in DV-format.

The length of frequency band in Y channel is 5.5 MHz, signal/noise ration is 55 dB. The compression level is 5:1, bitrate is 25 Mbit/sec, the amount of active image elements is 720×576. Sound is digital 16-bit with frequency sampling of 48 kHz plus lengthwise track. The recording time to standard DVCPRO cassette is 184 min, to DVCPRO M cassette is 66 min.

AJ-D455 is the first VCR of DVCPRO format, which provides recording in DV formats (except for LP mode), to standard as well as to miniDV-cassette. In the latter case the adapter is needed.

The user can regulate the level of sound recording in each channel when using digital and analogous entries. For sound level control there is an indicator. There is also function of correction of exiting image.

Editing accuracy is ±0 frames are provided by build-in facility of generating/reading of temporary code SMPTE/EBU, and presence of RS-422A interface provides an opportunity of remote control of device. It is necessary to mention that editing mode is out of orders in DV format and when using IEEE 1394 interface by-shot accuracy is not guaranteed.

When using external controller with support of function of slow reproduction the freeze frame mode is supported and reproduction at the speed of ±0.43 from nominal (without interpolation). Also with the help of external controller it is possible to perform speed search of material at 16-, 32- and 60-divisible speed in relation to nominal one.

The speed of search can be chosen from the menu. At such a search the image is reproduced to the monitor screen in the full color, however without reproduction of digital sound. The sound in this mode can be reproduced only from lengthwise tracks

Videocassette recorder is equipped with following interfaces:

• analogous entries/outputs: component, composite and S-Video by video and sound;
• RS-232C.

VCR has 4U size and weight of 14.3 kg and with the help of special adapter can be set in body. The power of the device is done from the mains of 220…240 V voltage, frequency of 50…60 Hz. Consumed power is 95 W.

AJ-D440 model differs from AJ-D455 by that it is a player. As to reproduction it almost doesn’t differ from AJ-D455 VCR, on the basis of which it is actually created.

AJ-D780 videocassette recorder of DVCPRO formats allow performing transfer of video audio material at four times speed in relation to nominal through SDTI interface. It provides digital component video recording with bitrate of 25 Mbit/sec. The device differs by frequency range of 5.75 MHz by Y channel, signal/noise ration not less than 55 dB, Presence of lengthwise analogous sound track and two-channeled digital sound section (PCM 48 kHz/16 bit).

For the change of system settings there is screen menu and compensation channels mode indicators allow defining the level of digital mistakes.

Except for SDTI, the device is equipped with input/output of analogous composite signal (BNC), output audio monitor (XLR), input of reference video signal (BNC), input/output of temporary code (XLR) and RS-422A interface.

DVCPRO50 AJ-D950 studio VTR

Studio DVCPRO50 AJ-D950 videocassette recorder is applied for solution of wide range of broadcasting tasks. It is capable to reproduce DVCPRO videocassettes (25 Mbit/sec) and is compatible with 525/60 and 625/50 television systems. VCR provides signal/noise ration less than 60 dB. The maximum recording time is up to 92 min when using AJ-5P92L videocassette. There is an opportunity of slow reproduction in limits of speed change of -0.43…+0.75 from nominal one. The speed of search with viewing can achieve 32× for DVCPRO50 and 60× for DVCPRO. VCR is equipped with build-in two-post video editing controller with memory for sound, which allows producing scoring. Except for that is foreseen recording of two service lines for TV text in interval of shot blanch pulse. Digital sound section is four-channeled PCM of 48 kHz/16 bit.

Communication opportunities of AJ-D950 are:

• SDI (BNC) input/output;
• SDTI input/output for DVCPRO signal (with additional AJ-YAC950P block);
• AES/EBU (XLR) input/output of digital sound;
• input/output of analogous component signal YUV and composite (BNC) (with additional AJ-YA955, AJ-YA956E, AJ-YA957E, AJ-YA958P blocks);
• input/output of analogous sound (4×XLR);
• output of audio monitor (XLR L/R);
• input of reference video signal (BNC);
• input/output of temporary code (XLR);
• RS-422A control interface;
• parallel control interface (25-male);
• RS-232C control interface.

AJ-D970 is the first studio videocassette recorder of DVCPRO50 format with pre-read function, which provides high quality of sound and video editing. This function allows not only performing assembly and insert, but also to perform voice superposition and perform special effects having just one VCR.

AJ-D970 VTR

Device works with digital video signal in 4:2:2 representations and four channeled digital sound. It is represented equipped with SDI entries/outputs. The universality of AJ-D970 is done also by that it can operate with recordings in DVCPRO format. Except for SDI, VCR is equipped with component and composite entries/outputs by video and analogous entries/outputs by sound (four channels). For remote control are foreseen RS-422A, RS-232C interfaces and parallel one (25-male).

It is necessary to pay separate attention to pre-read function. Simplified the process looks following: device reads image and sound from videotape, processes them, and then give the result of processing to the input. That is why editing can be done on one VCR. For superposition of voice-over can be used sound mixer, and for performing special effects, insert of titles and logotypes it is enough to connect VCR to video mixer or other corresponding facility.

When slow/speed reproduction the high quality of image is saved when the speed of tape’s moving changes in -1…+1 limits from nominal in modes as DVCPRO50, and DVCPRO. Speed search is possible with 32× speed in direct as well as in reverse direction. Besides, there is an opportunity of sound reproduction in speed range of -10…+10 from nominal one.

In DVCPRO50 format AJ-D970 can record to the tape of up to 92 min of material, and in DVCPRO format up to 184 min. If recording is done to DVCPRO cassette, then total time study is going to be twice smaller than it is said on the cassette. When reproduction VCR automatically defines the format of reproduced video. The use of intraframe compression provides the accuracy of linear editing of ±0 shots.

One more distinguishing feature of AJ-D970 is presence of build-in generator of TV signal, which is capable of giving synchronization mixture and text color bands. These signals can be recorded to the tape. Bar generator level can be switched between 100% and 75%.

Videocassette recorder weights 18.5 kg and consumes 235 W.

AJ-SD930 VTR

BM AJ-SD955 and AJ-SD930 represent the universal and effective studio videocassette recorders, assigned for editing of quality programs of the top level of difficulty. Both devices are equipped with SDI entries/outputs, RS-422A interfaces, what allows integrating them into the systems with editing controllers. Additionally, VCR AJ-SD955 itself is equipped with controller and that provides an opportunity to create editing couple on its basis.

AJ-SD955 and AJ-SD930 are capable of reproducing of material of DVCPRO, DV, and DVCAM formats as well as in DVCPRO50 format.

Except for digital, devices have also component and composite outputs by video plus entries/outputs of four channels of analogous sound. To provide operating with analogous video signals by input, it is necessary to set additional AJ-YAC932G board. There is also slot for setting of SDTI-board AJ-YAC930G. Besides, VCR is equipped with RS-232C for cooperation with computer, Encoder interface for remote regulation of video signal and parallel interface.

AJ-D940 also represents player of DVCPRO50 format, which is capable to reproduce recordings made in DVCPRO format.

Besides, there is an opportunity of switching of scanning mode 525/625. In DVCPRO50 mode reproduction of four channels of digital sound is provided and in DVCPRO mode two channels are provided. Rewinding time is less that 3 min when using AJ-5P92L cassettes. When using this device as signal source during linear system it supports editing accuracy of ±0 shots. Frequency range of lengthwise sound track is 300…6000 Hz (±3 dB). The user can regulate such video parameters as color and signal level. The player is equipped with SDI, analogous composite and component outputs, and additionally SDTI board can be set. For remote control different interfaces are provided (RS-232, parallel and some others).

DVCPRO HD equipment

Studio AJ-HD1600 VCR differs by that it supports new DVCPRO HD LP format. Recording time in this format is twice higher than standard one. This allows significantly lowering of costs connected with high definition television production. Especially for this VCR The Panasonic Company had developed XL videocassette, which recording time is 124 min. That became possible to achieve by double lowering of thickness of tape to 9 mcm against 18 mcm when using usual tape.

AJ-HD1600 studio VTR

Compatibility with other facilities of DVCPRO format at AJ-HD1600 corresponds to the level of the majority of devices: the reproduction of materials in DV, DVCPRO, DVCPRO50, DVCPROHD, and also DVCAM formats. When using AJ-CS455 adapter it is possible to reproduce even miniDV cassettes.

Short characteristics of AJ-HD1600 VCR are:

• recording and reproduction in 1080i and 720p formats;
• lifting/lowering converter;
• 4:2:2 representation;
• frequency band: in standard resolution is 1.5 MHz, in high is 74 MHz;
• eight sound channels, 16-bit digitalizing with 48 kHz frequency;
• speed of speed reproduction is up to 100× in relation to nominal one;
• control panel with build-in LCD-display;
• screen menu;
• recording of metadata when using additional VANC-board.

HD-D5 equipment

This category of equipment is the top of the technical thought of The Panasonic Company in relation to videocassette recorders.

AJ-D580 of D-5 format operates with uncompressed component 10-bit digital video in 4:2:2 representation. The width of tape is 1/2". The time of recording to milliroentgen cassette is 2 h. The user has an opportunity to choose the frequency of video sampling, which is about 13.5 or 18 MHz. As to the sound, it is 20-bit, sampling frequency is 48 kHz. There is also lengthwise analogous sound track, which simplifies the search of necessary fragment by phonogram. All editing functions are present in the device: assembly, insert, pre-read. Speed search can be done at the speed 50 times higher than the nominal one. Quality image is provided by changing of reproduction speed in -1…+2 range in relation to nominal. There is an opportunity of programming of reproduction speed changing in 85…115% range with 0,1% step. For remote control and realization of other opportunities are provided RS-422, RS-232, and parallel (50-male) interfaces. Besides, it is possible to correct video and sound signal levels remote.

Top of Panasonic’s technical achievements — AJ-HD3700

Created by The Panasonic Company AJ-HD3700 is one of the most perfect digital videocassette recorders.

The device is able to record and reproduce video of all high-definition television formats: 1080/59.94i; 720/59.94p; 1080/23,98p (sf); 1080/24p (sf); 1080/50i; 1080/23.98p; 1080/24p; 1080/25p; 1080/25p (sf); 576/50i and 480/59.94i. Maximum recording time to AJ-D5C124LP cassette:

• 124 min for video of 1080/59.94i, 720/59,94p, and 480/59.94i formats;
• 155 min for video of 1080/24p, 1080/23.98p (sf), 1080/24p (sf), and 1080/23.98p formats;
• 149 min for video of 1080/50i,1080/25p, 1080/25p (sf) formats;
• 112 min for video of 576/50i formats.

VCR is equipped with SDI and HD SDI interfaces, what allows integrating it almost in any production sphere. Formats converter, which is set additionally, provides lowering and increasing changes and also transfer of material from one high-definition television-format to another. The quality of material is provided by 4:2:2 representation in full frequencies band (without preliminary filtration) and10-bit digitalizing. When using additional AJ-UDC3700AG module on the output at the same time are formed signals of standard and high resolution. Besides video, on the output are given eight sound channels with 4-bit digitalizing and frequency sampling of 48 kHz, compatible with Dolby 5.1 and Dolby  E. Power of AJ-HD3700 is done from main of alternating current of 100…120 and 220…240 V voltage and frequency of 50/50 Hz (with opportunity of switch). Consumed power accounts for 330 W. Sizes of VCR are 424×220×520 mm, weight is 35 kg.

Obviously the range of digital videocassette recorders Panasonic doesn’t finish on these models, which entered this article. The description of other devices that are used in domestic TV production for a long time can be find in the review published in “625”, 2000, № 6, p. 21…30.

The Panasonic Company presented the material