Sony D8MM-01 Installation guide

Training Manual
Circuit Description and Troubleshooting
Course: D8MM-01
Digital
Camcorder
S

Introduction 1
New Camcorder Features 3
8mmandHi8XR(ExtendedResolution) 3
Laser Link 4
Nightshot 5
IEEE-1394 6
Advantages 6
Hardware 6
Protocol 7
CableTechnology 8
TradeNames 8
FutureDevelopments 8
Digital 8 Introduction 9
Digital 8 Basics 9
Compatability 9
Digital 8 Additional Features 10
Digital 8 Format 11
TrackLayout 11
Tape Speed 12
SubTrack Information 13
Tape WrapAngle 14
Video Signal Block 15
Table of Contents
D8 Record 15
D8 Playback 15
Analog8mmPlayback 15
D8 Record/Playback 17
D8 Record 17
D8 Playback 23
Analog 8mm Playback 27
Audio Signal Block 29
D8 Record 29
D8 Playback 29
Analog8mmPlayback 29
Servo Block 31
AnalogMode 31
D8 Mode 31
MechInitialization 33
DeterminingRecordingType 33
Power Supply 35
PSTroubleshooting 35
ASC D8 FRU System 36
Radar W 37
UsingRadarW 37
Upload/Download 38
Service Bulletin 42

1
Introduction
Overview
This book is designed to give the servicer knowledge of the new D8
camcorder format that will allow them to repair this product to the board
level. We will discuss this format in relationship to the analog Hi8/8 for-
mat. This information includes basic track layout, video and audio paths
and servo operation. Emphasis will be placed on areas that are not simi-
lar to the previous analog formats. Symptom/failure identification and the
differences in analog and digital tolerances to electrical and mechanical
misalignment will be discussed. We will also cover some of the new 8mm
features and the new Radar W jig.
Much of the new D8 circuitry will not be troubleshot to component level.
That is because the main board, VC-213, contains components that use
BGA technology. BGA stands for Ball Grid Array. This means that the
leads for these components are actually balls that are located underneath
the IC. These ICs cannot be removed or installed using conventional
soldering technology. The equipment needed is very expensive so all
componentlevelrepairswill bedone ata centralrepair depot. Youshould
also note that soldering is prohibited on the VC-213 board. This is be-
cause the BGA devices are extremely sensitive to sudden temperature
changes, such as that caused by a soldering iron. The only time a solder-
ing iron can be used on this board is if the data from the EEPROMs can-
not be uploaded. Then you are permitted to remove them and place them
on the new board.

2
NOTES

3
New Camcorder Features
Overview
In this section we will briefly discuss three new features found in Sony
camcorders. These features include 8mm and Hi8 XR, Night Shot and
Laserlink. These features can be used in any camcorder, analog or digi-
tal,with theexception of8mm XR,which isexclusive to 8mmcamcorders.
8mm and Hi 8 XR (Extended Resolution)
The 8mm Hi8/XR systems were produced in an effort to increase the
resolutionof new8mm productswhileremaining compatiblewith the8mm
and Hi8 systems. This system achieves 280 lines of horizontal resolution
versus 240 lines for 8mm. In Hi8 XR the resolution is increased from 400
lines to 440 lines. In order to understand this new technology, let’s look at
the old 8mm and Hi8 frequency spectrums.
Background
The 8mm Recording Signal Spectrum below shows the down converted
chroma signal to be centered at 743 KHz. The audio signal is centered
between the 1.5 MHz and 1.7 MHz audio carriers and the video signal
takes up the rest of the spectrum. The Y signal is frequency modulated
onto a carrier so that the sync tip is at 4.2 MHz and the peak white signal
is at 5.4MHz. The rest of the area inside the Y spectrum is for the side
bands produced by the frequency modulation of the video. Since greater
picture detail is located in the higher frequencies of the Y signal, the side
bands contain the picture detail. This means that if we can extend the
side bands area, we can produce more detail.
This is more evident when comparing the amount of side band informa-
tion in the Hi8 spectrum. The Hi8 system allows for greater picture detail
byallowing for awider side bandarea. Extending the bandwidthincreases
picture quality (resolution).
Conventional vs. XR (Extended Resolution)
In the conventional systems discussed above, a fixed band stop filter is
used during recording to keep the audio and Y signals from interfering
with each other. These filters are necessary in a conventional system,
but they do tend to eliminate some of the detail from the video. The XR
system is dynamic and the filter is not applied until the relative level of the
YFM in the AFM region is determined. If it is determined that the ampli-
tude of the YFM signal is low enough in the AFM area, then the filter will
be switched out. The resulting signal, which is sent to the head, is shown
below. This result is an extended resolution (XR) recording.
Analog 8mm Recording Spectrum
Hi8 Recording Spectrum
XR Record - Filter Out

4
If the system determines that the amplitude of the YFM signal is High
relative to the AFM, then the conventional filtering system will be em-
ployed. The result would be a standard resolution recording.
A conventional system uses the fixed band stop filter to separate the sig-
nals again in playback. The result is a standard resolution playback sig-
nal.
A dynamic band stop filter is used in the XR system. This filter senses the
presence of the relatively low YFM signal inside the AFM band and ad-
justs its filtering accordingly. The result is a YFM signal with extended
resolution.
Laserlink
Laserlink is a feature in Sony camcorders that sends Sircs information
and audio/video signals via infrared emitter to a Sony TV and an optional
IRreceiver. Thereis no noticeablelossofpicture quality betweenLaserlink
and composite video.
In order for the system to work you need the IFT-R10A infrared wireless
receiver or a new Sony Laserlink equipped VHS machine. This is an
optional accessory and is only necessary if you want to use the Laserlink
function. This accessory contains a composite video output that is con-
nected to your video display’s input. It also contains separate left and
right audio outputs that are connected to the component that will be pro-
ducing your sound.
In order to use the system, you simply point the camera in the direction of
the IR receiver and the TV and press PLAY. Sircs signals are then sent
from the camcorders infrared emitters. The first of these signals is the TV
ON command and the second is the selection of the video input source.
You can select Video 1, Video 2 and Video 3 or OFF using the camera’s
menu. You may also select whether or not you would like the Power ON
command sent by using the camera’s menu. Once the Sircs commands
have been sent, audio and video information is transmitted from the
camera’s infrared emitters to the infrared receiver. The receiver decodes
the infrared signals and outputs them so that the picture can be seen and
the sound heard.
Conventional Record - FIlter In
Conventional Playback
XR Playback
Laserlink

5
NightShot
NightShot is the name Sony has given to its 0 Lux system. 0 Lux means
that camcorders with this feature can literally see in the dark. How is this
miraculous feature possible?
The main technology used for NightShot has been inherent in the
camcorder lens system for years. The lens focuses outside light on the
CCD, which can see light in the infrared spectrum. As a matter of fact, a
normal camera lens has an IR-cut filter built into it to dramatically cut
down the CCD’s sensitivity to infrared light. This brings the sensitivity of
the camcorder closer to that of the human eye.
We can use the CCD to its full potential if we take out the IR-cut filter.
Without the filter, the picture appears to be completely washed out in the
presence of light. This allows objects to be seen in the dark. NightShot
utilizes both types of systems by using a mechanical switch to move the
IR-cut filter in and out.
When the NightShot switch is turned ON, it turns ON the Laserlink LEDs
located in front of the camcorder, as well as physically moving the IR-cut
filter. Thelightemitted bytheseLEDs is projectedinfront ofthecamcorder
and acts like a spotlight. The LEDs allow images to be seen in the dark
up to three meters away. Optional accessories are available that emit
more infrared light and allow images to be seen up to 100 feet away in the
dark.
The NightShot picture has a couple of “quirks”. When viewing video shot
using NightShot, the color is not correct and appears washed out and
greenish in tint. The other problem is the presence of a “hot spot”. This
hot spot is normal and is caused by the varying intensity of the LEDs that
project infrared light in front of the camera. It can be thought of as if a
flashlight were being used as a light source while shooting. Due to the
unevenness of the light source, one area would appear brighter than the
rest.
CCD Sensitivity
NightShot Range
IR Cut Filter MEchanism

6
IEEE-1394
Overview
IEEE-1394 is high-speed digital interface that can be used by many types
ofproducts, includingcomputers andconsumer electronics. Ituses trans-
action-based packet technology to communicate between devices. This
standard was developed to help bridge the gap between PCs and con-
sumer electronic products.
Advantages
The IEEE-1394 has been chosen as the standard interface for digital con-
sumer products because of its many advantages. Listed below are sev-
eral of these advantages:
§It is a hot pluggable and unpluggable system. Devices may be added
or removed at anytime and their presence or absence will be recog-
nized by the system.
§It is a non-proprietary standard adapted by the Institute for Electrical
and Electronic Engineers. There are no licensing problems at this
time to keep companies from adapting this format.
§It allows for flexible hookups and easy connection. One thin cable
between devices does it all. The system allows for daisy chaining up
to 63 devices together at one time and also supports branching. It is
Plug and Play and does not require ID jumpers or switches. There is
no need for terminators.
§Peer to peer communications are possible. Any device should com-
municate with any other device without a need for a hub or a PC to be
connected.
§The system uses scalable architecture that will allow older, slower
devices to communicate with newer, faster devices at the slower rate.
Different combinations of faster and slower devices can be used on
the same bus.
Hardware
There is hardware currently available to support speeds of 100, 200 and
400 Mb/s (Megabits per second). These speeds are fine for digital video
since it has a data rate of 30 Mb/s. Data rates of 800 and 1600 Mb/s are
already scheduled for release. A data rate of 3200 Mb/s is in the planning
stage.
IEEE-1394 consists of three layers of hardware called the physical, link
and transaction layers. These components may be found in a single IC or
in several ICs. These layers will perform the same function regardless of
how many ICs there are. A description of each layer is listed below:
§Physical Layer – Provides the electrical and mechanical interface
between a device and a connector. This layer also provides initializa-
tion and arbitration between devices. There is a built-in arbitration
subroutine that will make one of the devices the bus master. This
device will assign IDs to the nodes (devices connected) and control
traffic.
§Link Layer – The link layer handles all data packet transmissions and
receptions. The data can be either asynchronous or isochronous.
Typical IEEE1394 Hookup
PEER to PEER Connection

7
§Transaction Layer – Manages asynchronous data protocols. This
layer is also responsible for communicating between a device that is
using IEEE 1394, such as a digital camcorder or a capture card, and
the link layer. This would be the system control IC in a camcorder and
the PCI bus in a PC.
Protocol
Data Transfer
There are two types of data transfer possible using IEEE-1394. They are
as follows:
§Asynchronous – This is a memory mapped system. Each packet of
data is sent to a specific address to be stored and buffered by the
recipient. An acknowledge signal is sent when the data is properly
received.
§Isochronous - Isochronous data needs to be sent and received at a
steady rate that is in close timing with the ability of the receiving de-
vice to process the data. For example, if a digital camcorder pro-
cesses data at approximately 30 Mb/s, then the receiving device must
be able to use this data at the same rate. Data is essentially broadcast
at a predetermined rate and not checked for accuracy.
Dynamic Node Addressing
Each device, called a node, is assigned a specific address. This occurs
when a bus reset occurs or a new device is added to the system. Three
steps occur when these events happen:
§IDs Cleared - All previous ID information is erased.
§Tree ID - The device, which is the bus master, assigns each node a
specific address. This is called the Tree ID Process.
§Self-ID - After IDs have been assigned, the system allows time for
each device to identify itself to the other nodes in the network.
Multi-Speed Transactions
The IEEE-1394 allows for data transmission speed to vary over the net-
work. If necessary, a faster device will change its speed to communicate
with a slower one. The paths taken between devices also limit data rates.
In Example A below, the PC or scanner would have no trouble communi-
cating with the camcorder at a rate of 100 Mb/s. However, the scanner
could not communicate with the PC at its top data rate of 200 Mb/s be-
cause the path between the two contains a 100 Mb/s device (the
camcorder). The maximum data rate that can be achieved through an-
other device is limited to the speed of that device. In example B, the PC
and the scanner would be able to communicate at the scanner’s top rate
of 200 Mb/s. It is very important that when an IEEE-1394 network is set
up that care is taken to properly place devices that need to communicate
with each other at top speeds.
Example: IEEE1394 Interface in Camcorder

8
Cable Technology
Wire
A standard six-wire cable is used by the PC industry as an IEEE-1394
connection. There is also a four-wire connection used by Sony and other
manufacturers on digital camcorders and similar devices. The six-wire
cable contains B+, Gnd, and one differential pair for transmitting data and
one differential pair for receiving data. The four-wire cable only contains
the two differential pairs for data. There are adapters available if one
device uses a 4-wire cable and other uses a 6-wire cable.
Connector
The connectors are simple sturdy and reliable. They are designed with
the contacts inside the connector to reduce corrosion and shock hazard.
Theyare childproof,ifthere issuch athing, and arebased onthe Nintendo
NES™ connector.
Trade Names
There are a few trade names associated with the IEEE-1394 standard.
The most notable are Firewire, which is an Apple trademark and i.LINK,
which is the Sony trademark.
Future Developments
IEEE1394 seems poised to take its place as the home networking stan-
dard of the future. Its high speed and ease of use are part of the keys that
may one day make it the bond between all the components in your home.
Sony, along with other industry leaders, is working on a standard called
HAVi. HAVi, which stands for Home Audio Video Interoperability, would
be an “open architecture” system. This means that software, application
programming interfaces and communication protocols will allow all digital
electronic components to work together regardless of manufacturer. This
might mean that you could control your DTV set top box, digital audio
system and the temperature of your refrigerator all from one central loca-
tion. The amount of products that may use this system is limitless. We
are heading for a digital future and it seems that IEEE1394 will be a large
part of it.

9
Digital 8 Introduction
Overview
Digital 8, or D8, is a new format developed by Sony. It is not an extension
or an improvement of the analog 8mm systems, like XR, but a totally new
format. The analog 8mm systems include standard 8mm and Hi8. How-
ever, this new format does use the same tapes as Hi8 and is backward
compatible. This means it can play back old 8mm tapes, including tapes
recorded in LP or SP modes. The symbol below is the logo for Digital 8.
It will be seen on all new products that are Digital 8 compatible.
Digital 8 Basics
Digital Recording/Playback
The Digital 8 format uses technology that was developed for the DV bit
stream recording and playback. DV is the name of the standard that uses
6mm wide tape to record and play back digital images. This format is also
referred to as DVC.
Analog Playback
Digital 8 camcorders will play back your old 8mm recordings. This in-
cludes SP and LP recordings in Hi8 or standard 8mm. These cameras do
not record in analog.
Compatibility
Cassette
The Digital 8 system uses Hi8 tapes. These tapes will be marketed in the
future as Hi8/D8 tapes. Standard 8mm tapes should not be used as they
may cause compatibility issues between D8 camcorders because of the
type of metal particulate material they use. Note: All compatibility is-
sues related to making digital recordings using standard 8mm tapes
are not to be recognized as servicing issues.
There is one drawback to the use of existing tapes. Due to the nature of
the Digital 8 format, the recording time will be half what it would be in a
standard analog 8mm format. This means that an E6-120 type cassette
would only have a 60-minute recording time instead of the usual 120 min-
utes. New tapes that contain the D8 logo will have both times clearly
marked on the tape.
Mechanism
The new Digital system is completely backward compatible with the older
analog 8mm system and the newer 8mm XR and Hi8 XR systems. The
drum is the same diameter, the wrap is the same and the head azimuths
are the same. In fact the mechanism used in 1999 D8 camcorders is a B
mechanism. The B mechanism has been used in all Sony 8mm/Hi8
camcorders for the last several years. There are some differences be-
tween a standard 8mm B mechanism and a D8 B mechanism, such as
more precision drum and capstan motors, but functionally they are the
same. These differences are necessary due to an increase in speed of
both servos during Digital 8 recording and playback.
New Drum Motor
The Digital 8 camcorder automatically recognizes the type of recording,
digital or analog, on the tape and adjusts its servos to play that type. The
camcorder is set up to start with its servos in the mode they were in pre-
viously. If a different format is detected, the servos will automatically
D8 Logo

10
1999 Digital 8 Standard Features
There will be five basic Digital 8 camcorders released this year. One
model, DCR-TR7000, will be part of the TR series of camcorders. Four
willbepartoftheVision series andtheirmodelnameswillbeDCR-TRV103/
110, DCR-TRV310 and DCR-TRV510. Vision series camcorders contain
a color LCD panel on the side for easy viewing. These camcorders have
manyfeatures thatstandard 8mmcamcorders have,including AEmodes,
digital picture effects and world time clock. They also contain the follow-
ing important features:
§InfoLithuim Battery - The InfoLithium Battery is a lithium-ion battery
pack which can exchange data with the camcorder about its battery
consumption and charge time remaining. This results in increased
battery life.
§20x Optical/360 Digital Zoom – These models feature an optical and
digital zoom. The digital zoom can be turned off using the customer’s
menu.
§Nightshot – The 0 Lux feature allows an image to be seen without
light. This year’s Nightshot uses a slow shutter mode to increase
image quality.
§Intelligent Shoe – Allows Sony’s intelligent accessories to be used
with these camcorders.
§Laserlink – This feature can be used with an optional accessory to
send audio/video information across the room without wires. It is an
infrared system.
§Digital Stereo –Sound canbe recordedin 12-bitor 16-bitdigital PCM
Stereo.
§PhotoMode - Allows you to capture a still image for seven seconds
while the audio continues recording, allowing you to provide narration
for the still image.
§SteadyShot – Stabilizes the image being recorded by reducing shak-
ing. SteadyShot utilizes motion sensors located in the lens assembly
area that are designed to sense camcorder motion
§i.LINK – This is Sony’s IEEE1394 interface. It allows you to edit, dub,
archive or playback between two digital components with virtually no
generation loss. These digital components include camcorders, com-
puters, DTV set top boxes and many more.
§Data Code – Stores the time and date of the recording on the tape.
The user can access this information at any time.
§16:9 Wide Mode – Allows you to record and playback in “widescreen”
mode. During record the camcorder takes advantage of the over-
sized imager used for SteadyShot to produce the wider image. You
should note that SteadyShot does not function in 16:9 Wide Mode.
Digital 8 Additional Features
Listed below are some of the additional features of the basic models.
These additional features determine the differences between models:
§Color Viewfinder
§LCD Size
§DSC (Digital Still Camera) –. A model with this feature emulates a
still camera by storing a field or frame of video in “flash” memory in
JPEG files. These files can be read from the camera through the use
of a built-in RS-232 port, which would be attached to a PC, and soft-
ware that comes with the camcorder.
switch to the other format. This auto-detection action takes about six to
eight seconds from distinguishing the type of recording to the beginning
of playback. Tapes may also contain any combination of standard 8mm,
Hi8 or D8. When a different format is detected during playback, the tape
is stopped, the servos are adjusted and playback begins using the new
format. You will also see one of the two displays below over a blue back-
ground depending on what type of change is taking place.
Model Viewfinder LCD Size DSC
DCR-TR7000 Color N/A No
DCR-TRV103/110 B/W 2.5” No
DCR-TRV310 B/W 3.5” No
DCR-TRV315 Color 3” No
DCR-TRV510 Color 4” Yes

11
Digital 8 Format
Overview
This section will discuss the new format used to record digital information
on a tape. This format will be compared to the analog 8mm format so that
it easier to understand how Digital 8 was created to remain compatible
with analog 8mm, while giving us the benefits of digital recording.
Track Layout
In the analog 8mm system, the heads would put two swipes or tracks on
the tape for each frame of video. Two tracks on the tape are equivalent to
one frame of analog video information. Therefore the drum rotates at a
frame rate of 30Hz or 30 complete revolutions per second. The result
would be a drum speed of 1800 revolutions per minute (rpm).
In the D8 system, the heads put five swipes or tracks on the tape for each
frame of video. These swipes are broken down into sub tracks and there
are two sub tracks for every track. The reason for this is to keep the
technology similar to the DV format, which uses ten tracks per frame of
video. The drum speed needs to be increased in order for the system to
use five tracks per frame. At a drum speed of 75 Hz, or 75 revolutions per
second, we can place five tracks on the tape for each frame of video
using two heads. The result is 150 tracks of information placed on the
tape at a drum speed of 4500 revolutions per minute (rpm). It is important
to note here that the way the information is placed on the tracks will have
a great impact on the symptoms that will be seen when the tape path is
misaligned or a head is clogged or lost.

12
Tape Speed
Since the drum speed was increased, there became a need to also in-
crease the tape speed. If the tape speed were not increased, 150 tracks
would have to be squeezed into the same area on the tape as 60 tracks.
The system could not function this way and use the same heads. Conse-
quently, the tape speed has been roughly doubled from 14.345 mm/sec
to 28.666 mm/sec. This allows digital 8 to have a track pitch (width) that
is close to that of analog 8. This allows for the use of the same heads for
analog playback and digital recording and playback.
Analog 8m m D igital 8
Track Information Analog Digital
Tracks per frame 25
Tracks per second 60 150
Drum rotation speed 1800 rpm 4500 rpm
Track pitch (width) 20.5 um 16.34 um
Tape speed 14.345 mm/sec. 28.666 mm/sec
Recording time P6-120 120 minutes 60 minutes

13
Sub Track Information
The sub track information can be broken down into four distinct sectors.
These are called the ITI, Audio, Video and Subcode sectors. Each of
these sectors is separated by a gap. These gaps are there to allow for
small tracking errors that may occur when editing.
Each sector has its own designated purpose:
§ITI Sector – ITI stands for Insert and Track Information. It is used to
control the tracking for insert editing. It also contains data that identi-
fies the track format. The ITI sector contains 3600 bits per sub track.
§Audio Sector – This contains the audio information and parity bits
used for error correction. The audio sector contains 11,550 bits per
sub track.
§Video sector – This contains the video information and parity bits
used for error correction. The video sector contains 113,225 bits per
sub track.
§Subcode Sector – This contains an ID block which contains an index
ID, PP-ID (still picture search marker), Skip ID and absolute track
number. The data block contains subcode data for time code, REC
date and REC time. Parity information is also contained in this sector.
The subcode sector contains 3725 bits per sub track.
In addition to the sectors, there are three Gap areas between the four
sectors. They are called Gap 1, 2 and 3 and contain a preset run of bits.
These gaps contain 625, 700 and 1550 bits respectively.
If we add up the total number of bits in a complete sub track we will count
134,975 bits. Since there are ten sub tracks per frame, we have 1.35Mb
per frame. Since the NTSC signal contains 30 frames per second, we will
have a total of 40.5Mb per second.
Alternating Head Pattern
Since there is an odd number of tracks in one frame, it is important to note
that the head pattern alternates every frame. This gives us two distinct
head patterns for a frame, ABABA and BABAB. This becomes an impor-
tant fact since a bad head will cause a flickering of the picture in five
distinct bands.

14
Tape Wrap Angle
The tape wrap angle for an analog 8mm system must be at least 180
degrees for video to be recorded. This means that one head is in contact
with the tape for the full 180 degrees and lays down one field of video
information.
The physical tape wrap of the B mechanism is 211 degrees. This means
the tape wraps around the drum for 211 out of a possible 360 degrees.
211 degrees is used because it makes the mechanism compatible with
8mm PCM, but that feature is no longer available in US camcorders and
hasn’t been for several years. Camcorders that use a B mechanism use
switching to limit the effective wrap of the tape to 180 degrees.
D8 uses the B mechanism and also does not need the entire 211 degree
wrap. D8 uses switching to limit the effective wrap angle to 177 degrees.
The first 87 degrees of this effective wrap are used to put down the first
sub track. The next three degrees are used for ITG. ITG is the Inter
Track Guard that separates two sub tracks. The remaining 87 degrees
are used to place the second sub track on the tape. This process contin-
ues while the tape is playing or recording.
D8 Envelope Analog Envelope

15
Video Signal Block
Overview
The purpose of this section is to discuss the three different video paths.
The three paths are D8 record, D8 playback and analog 8mm playback.
We will discuss this in a block level only since component troubleshooting
is not necessary. This will help to give you an overall idea of the three
signal paths.
D8 Record
Recording can be done either by using the signal from the camera sec-
tion, analog line input or through the IEEE1394 input.
Camera Front End Processing
The camera front end-processing block contains the lens, CCD, timing
generator and associated circuitry. This section processes the CCD im-
age data and outputs 10 bit CCD Data to the Tanuki (Traffic Cop) section.
Tanuki (Traffic Cop)
A portion of this section’s function is to process the information from the
camera front end processing block. This would function similar to a por-
tion of the core IC in an analog 8mm camera. This IC outputs data to the
DSP/Compression block.
Line In
When a line input signal is to be recorded, it is input to a A/D Converter on
the main board. The signal is digitized and output to the compression
section. This data is sent on the same bus as the data from the camera
section.
DSP/Compression
This section compresses the data, reducing the amount of video data
from 162 Mbps to 25 Mbps. It also codes the data and interleaves it with
the ITI, Audio and Subcode data. This data is then streamed to the Head
Amplifier. It also outputs the compressed video to the IEEE1394 inter-
face, as well as analog signals for the viewfinder and Line Out.
Head Amp
The head amp adds a clock signal and amplifies the data. It is then ap-
plied to the heads and recorded on the tape.
D8 Playback
Head Amp
Theheadamp receivesthesignal fromtheheads andamplifiesand equal-
izes the signals from each head. This section also inputs the RF signal to
a PLL circuit, which produces a stable clock for processing the head data.
DSP/Decompression
This block separates the data back in to its various sectors. The video
data is decompressed and restored back to an analog video signal. It
outputs analog signals to the viewfinder and Line Out, as well as a digital
signal to the IEEE1394 interface.
Analog 8mm Playback
Head Amp
The head amp creates a separate RF signal if an analog tape is played
back.
8mm Playback RF Amp
This block separates the Y RF and C RF signals.
Camera Front End
The C RF signal is applied to this block. This block digitizes the C RF
signal and applies it to the Traffic Cop block via the 10 bit bus.
Tanuki
This block receives the Y and C RF signals and demodulates them. It
outputs analog Y and C to the A/D converter. The A/D converter is the
same one used by the Line In circuit in D8 record. Its output is applied to
the DSP/Compression block.
DSP/Compression
The signal is sent to this block so that it can be output to the line out
and viewfinder. It is also compressed so that it can be output to the
IEEE1394 interface.

16

17
D8 Record/Playback
Overview
The purpose of this section is to explain the theory of the digital video
signal paths in the D8 camcorders. This is just an overview of the theory.
Much of the detail has been left out because of its complexity and the fact
that this product will only be repaired to board level. Note: You should
only expect to have a basic understanding of what is done to the
video signal, not a complete understanding. The diagram can also be
used for board level troubleshooting. It shows you the connectors that
leave the VC-213 board. You can troubleshoot to board level by deter-
mining if the signals are leaving or going to the proper connector pins.
D8 Record
Recording can be done by using the signal from the camera section, the
analog line input or through the IEEE1394 input.
Camera Signal Processing
The camera processing block contains the lens, CCD, timing generator
and associated circuitry. This section processes the CCD image data for
use by the camera core.
IC251 Tanuki
Video Processing – A portion of this IC’s function is to process the infor-
mation from the camera signal processing block. This would be the core
IC in an analog 8mm camera. This IC outputs Y and C signals to IC601
BBI.
IC601 BBI
The BBI functions as an A/D Converter for the Line Input signal. It out-
puts 8 bits of Y and 4 bits each of the color difference signals, Cb and Cr.
It also outputs horizontal and vertical sync signals.
Compression Block
The block diagram below outlines the steps that need to be taken to com-
press the amount of video data from 162 Mbps to 25 Mbps. Each frame
of video is processed alone. This is called Intra-frame compression. It is
different from MPEG 2 because the MPEG system does not compress
each frame individually. The MPEG compression type scheme is called
Inter-frame compression.
Each frame of video is loaded into a frame memory. This frame is used
alone and not compared to any other frames. The picture is then divided
into blocks by the Blocking stage. These blocks are then combined so
that the data from different parts of the frame is used. This process,
called shuffling, maintains an average compression ratio throughout the
frame. The video from these shuffled blocks is then compressed. After
compression the data is put back in the appropriate order through a pro-
cess called de-shuffling. This data is then coded, amplified and applied to
the tape.

18