SONY DTV 01 Service Manual

S®

High Definition Television

Training Manual

Circuit Description and Troubleshooting

Course: DTV-01

Table of Contents

Introduction 1 HDTV Transmission Stream 3 Introduction to MPEG-2 Compression 9 Model KW-34HD1 - Normal Operation 19 Inputs 21 Overall Block 25 SIGNAL PROCESS Video Block 1 29 Video Process A 31 Video Process B 33 Video Block 2 35 Digital Realty Creation 37 MID - Multi Image Driver 4 1

POWER SUPPLY Power Supply Block 55

Standby Power 53 Converter 2 61 Overall Protection Block 67 D Board Protection Block 71 Protection Circuit 1 73 Protection Circuit 2 75 Protection Circuit 3 77 Protection Circuit 4 81 DEFLECTION Vertical Deflection 85 Horizontal Deflection Block 89

Video Process C 43 Video Block 3 45 Video Process D 47 On Screen Display 49 Video Process E 51 Screen Voltage Control 53

Horizontal Drive 91 Horizontal Driver 93 Horizontal Output PWM 1 97 Horizontal Output PWM 2 10 1 Pincushion Correction 105 Picture Tilt Circuit 109 Dynamic Focus Block 113

Dynamic Focus 1 - B+ Mfg. 11 7 Dynamic Focus 2 - Location 121 Dynamic Quadrapole Focus 125 Appendix

Set-Back Box i Picture Size Modes iii Board Replacement iv Service Mode Display vi

Introduction

TV Transmission Formats

Standard Definition/High Definition

Picture resolution is commonly measured in pixels or lines. The number of pixels is the number of black to white brightness changes possible on the screen first in a horizontal, then in a vertical row (e.g. 960x480). CRT manufacturing tolerances limits the number of pixels possible. This is a common resolution specification in a computer monitor CRT.

In a TV broadcast, the studio camera is the limitation to higher resolution. The picture scanned by the camera is segmented by pixels similar to the viewer’s CRT. The greater the number of pixels in the horizontal and vertical row, the greater the resolution. This will be the current resolution limitation as the USA makes the transition toward high definition digital TV .

In a TV transmission, the ability of a signal voltage to quickly change from low to high and to produce a dark to white transition is comparable to a pixel. This is not a limitation in the transmission format, but the number of lines transmitted is and is used as a resolution measurement in transmissions. The number of lines transmitted in the current USA NTSC format is

525. This is considered a standard definition (SD) transmission. A standard definition (SD) transmission of 525 lines can be transmitted in

the analog or digital mode. A higher definition (HD) transmission can be transmitted only in the digital (DTV) mode.

¨ SDTV or SD – Standard definition is the current 525 lines of resolution

transmitted, but only 480 of those lines are viewable. SD can be sent as an NTSC analog or digital (DTV) transmission.

¨ HDTV or HD – A high-definition transmission contains 720 or more

horizontal lines. HD is transmitted only in a digital format.

¨ DTV – A digital TV transmission refers only to the digital encoding of

the picture signal that may contain either a high (HD) or low (SD) resolution picture. The digital picture is not viewable on an analog TV without a “decoder box”.

Digital Transmission Formats

There are 18 approved digital transmission formats. The first six offer HD signals in a 16x9 aspect ratio. The remaining 12 formats are SD signals in progressive (p) or interlaced (i) scan. Although not high resolution, they offer significant improvements over the NTSC analog signal.

18 Digital Transmission Formats

Resolution

1. 1920x1080 16:9 30 i 10. 704x 480 16:9 24 p

2. “ 16:9 30 p 11. “ 4:3 60 p

3. “ 16:9 24 p 12. “ 4:3 30 i

4. 1280x 720 16:9 60 p 13. “ 4:3 30 p

5. “ 16:9 30 p 14. “ 4:3 24 p

6. “ 16:9 24 p 15. 640x 480 4:3 60 p

7. 704x 480 16:9 60 p 16. “ 4:3 30 i

8. “ 16:9 30 i 17. “ 4:3 30 p

9. “ 16:9 30 p 18. “ 4:3 24 p

A standard definition transmission permits space for another digital video stream to coexist on the same frequency (channel). Consequently a station can have more than one program stream on a digital channel. The maximum number is not known at this time.

Aspect Ratio

Frames Resolution

Aspect Ratio

Frames

How to use this book for servicing

Service Mode Adjustment Notes

When encountering this TV set for servicing there are several things you need to know. Below is a list of the necessary servicing items and where to locate them:

Servicing Needs

Information Location

1. Hookup / Operation / Normal Operation

2. External HDTV set-back box indicator lights

3. Location of power handling parts and fuses

4. Standby light indication message & board determination

5. Shutdown troubleshooting plan Protect Circuitry 3 & 4

6. Power Supply, Deflection, Video Selection and Signal Flow Circuitry

7. Focus Circuitry Circuitry in this training book

8. Dynamic Convergence adjustments Service manual page 27

9. Adjustments after tube replacement Notes on using the service

First document in this training manual (Normal Operation)

Appendix

Service manual / visual inspection of heat sinks

Service manual and Protection Block document

Circuitry in this training book. See table of contents.

(same as in training manual supplement)

mode follow this chart. A list of register names are in

the service manual. Training manual supplement

Because of this TV’s complexity , the following precautions should be noted while making service adjustments for convergence, video level, size, and white balance or positioning:

1. The numerous service mode registers are usually grouped by ICs for easy access. Use the remote’s #2 and #5 button to change IC groups. Then you can move from register to register with the #1 and #4 buttons.

2. Each register that controls the picture’s size, deflection and position (on pages 45-47 of the service manual) has seven sets of adjustment data, one for each of the seven picture size modes. These settings do not interact. Enter the service mode, adjust the TV during that picture size, and store it.

Seven Picture Size Modes

NTSC or SD DTV HDTV

1. Normal 4:3

4. Wide Zoom 6. HDTV Full

aspect ratio

2. Full 16:9 aspect ratio

3. Zoom

1. Some registers are duplicated under different groups for ease of adjustments. These duplicated registers have the same name. Changing the register data at one location causes the data to change at the other location as well.

2. Save adjustments often. Changing registers will hold the new data, but changing picture sizes (zoom, full, caption, etc) will instantly lose any unsaved data that was just held.

3. There are separate contrast, color level, and hue adjustments for:

¨ The main picture ¨ The HDTV picture ¨ Each twin view picture

They are adjusted for equal levels as you switch modes. This is so the picture is not brighter in one mode than another.

5. Caption (Top & bottom pix

compressed)

7. HDTV Twin View

Introduction to MPEG-2 Compression

MPEG stands for Motion Picture Experts Group, named after the committee that developed the standard.

Why Compress?

MPEG defines a compression scheme for Video which evolved from the need to transmit digital video on existing communication channels with limited bandwidth. In addition to the bandwidth issue there is an obvious storage one as well.

Fastest Communication Channels Typical Bandwidth

ISDN Line 144Kbps T1 Line 1.5 Mbps T3 Line 45 Mbps With a whopping 4.7 gigabytes of data capacity, DVD-Video would seem

to have more than enough room for motion pictures. Unfortunately , digital video has an incredibly voracious appetite for storage.

Raw or uncompressed Digital Video requires an enormous 252 Megabits/sec of bandwidth and approx 31 Mbytes per second of storage.

720x480 (Res.) X 8bits/sample X 30frames/sec X 3 Components

To understand this figure, we need to understand video in its purest form.

Component Video

Each sample we take of the video is represented by an 8 bit digital word which translates to 2 fore, each pixel is made up of 3 components which can represent up to 28 (Y) X 28 (R-Y) X 28 (B-Y) = 224 (commonly known as 24 bit color)or 16 million colors.

The resolution or picture detail we require also plays an important role in our bandwidth and storage requirement. DVD uses a 720 Horizontal by 480 Vertical resolution or 720 pixels across times 480 rows or lines.

In summary we need to:

- sample 3 components (Y, R-Y and B-Y) each of which is composed of 720 x 480 (350,000) pixels.

- Represent each one by an 8 bit word (3 X 350,000 X 8 = 8,400,000bits). Therefore, each frame is made up of 8,400,000 bits.

- Finally, we would need to display at 30 frames per second (30 X 8,400,000 =252,000,000 bits/sec or 252 Mbits/sec Bandwidth.

or 256 different levels of each component. There-

R-YB-YY

One PIXEL

720

480

In its purest form, Video is made up of 4 components.

- Luminance or Y which defines the brightness level and

- Color which is made up of 3 components called R-Y, B-Y and G-Y. As it works out, we can mathematically calculate the 4th component (G-

Y) from the others. Therefore, we only require 3 components for Video (Y, R-Y and B-Y).

Y = (R-Y) + (B-Y) + (G-Y)

To calculate the storage we simply divide the Bandwidth in bits by 8 bits per byte and we get 31.5Mbytes/sec Storage requirement.

As illustrated, the requirement is enormous which paves the way for compression and MPEG.

Compression Process

4:2:2

Compression of Video is accomplished via the following process.

1. Selective Sampling

2. Discrete Cosine Transform (DCT)

3. Predictive & Motion Encoding

4. Hoffman Encoding

Selective Sampling

The number of times per second that you sample a signal is called its sampling frequency . In Audio, the sampling frequency is 44,000 samples/ sec which is approx 2 times the highest frequency in Audio (20,000 Hz). In contrast, Video is sampled at 4 times the highest frequency (13.5Mhz). Hence the term 4 in the sampling structure 4:4:4 representing the sampling ratio of Y, R-Y and B-Y respectively.

Therefore, the same number of samples are taken of Y as they are of RY and B-Y.

Signal

Since the eye is less perceptive to color changes than to Luminance, significant reduction of data can be accomplished in the Sampling process if we sample the color components (R-Y and B-Y) half as much as the Luminance component (Y). The result is a 1/3 reduction or a bandwidth of 166Mbits/sec. Video sampled using this technique is represented by a 4:2:2 sampling structure. Y is sampled normally with R-Y and B-Y sampled half as much.

ONE

PIXEL

LINE 1

LINE 2

. . . .

LINE 480

Samples taken in the Horizontal direction up to 720 per Line

R-Y B-YY YR-Y B-YYY R-Y B-YY YR-Y B-YYY

Non Sampled components Illustrated as clear boxes

4:1:1

Time

Consequently techniques such as the 4:1:1 further reduce color sampling to 1/4th of the Y component and compress by ½ or reduce bandwidth to 125Mbits/sec.

4:2:0

DVD takes it to another level by using a modified 4:2:2 sampling structure called 4:2:0. 4:2:0 samples R-Y half as much as Y and skips B-Y on the 1st line. However, on the next horizontal line, B-Y is sampled half as much as Y and R-Y is skipped. This routine is repeated effectively reducing the color components by another half achieving ½ compression or a 125Mbit/sec bandwidth. Through interpolation, the 4:2:0 is reconstructed into 4:2:2 without the extra bandwidth requirement.

ONE

PIXEL

LINE 1

LINE 2

LINE 3

LINE 4

. . . .

LINE 480

Samples taken in the Horizontal direction up to 720 per Line

R-YY YR-YYY

B-YY Y

R-YYYR-YY

Y B-Y Y

Non Sampled components Illustrated as clear boxes

YB-YY Y YB-YY

The high frequency information consumes the most data real estate and is where we focus to compress in this next stage.

The process of eliminating the imperceptible information is called Discrete Cosine Transform or DCT. The sampling process converts the information into digital data as described previously. Each digital picture frame is then sectioned off into 5400 blocks each consisting of 8 pixels wide X 8 pixels high.

1 of 5400 Blocks

Picture

Frame

8 X 8 Pixel Block

Discrete Cosine Transform

After the Selective Sampling process is complete, the next step in the MPEG process is to remove very fine picture detail imperceptible to the human eye. It is imperceptible because it is typically masked by other picture content.

In a Video Frame, the very fine picture details consist of high frequency information which are basically fast changing Luminance and Color content. In contrast, low frequency information are slow changing Luminance and Color content.

DCT transforms the 8X8 group of pixel values into frequency components.

Although pixel values vary randomly in the 8X8 block, DCT re-positions low frequency components on the upper left corner and high frequency components on the lower right of the block. Through an additional numerical conversion process called “Quantization”, frequency component values are assigned.

High freq components are identified by the zero values (lower right) and low freq components by the larger values (upper left).

Data compression is accomplished by elimination of the high frequency components designated by the zeros.

8 X 8 Pixel Block

Temporal Redundancy

Within Video scenes, there are many redundant frames. An example would be an anchor person reporting the news. With the exception of lip movement, the other portions of the frame remain unchanged over time. This type of redundancy over time is called “Temporal Redundancy”.

LFreq HFref

10 5 1 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

HFref

Spacial Redundancy

Within a Frame, there are many redundant pixels. An example would be a blue sky. This type of redundancy within the Horizotal and Vertical plane of a frame is called “Spacial Redundancy”.

One pixel could be stored with information to repeat for the remaining pixels. This would eliminate the need to store every pixel in the frame.

Frames making use of this technique are called “Intra-Frames”.

The first frame could be stored as the reference or non changing portions while remaining frames carry the lip motion information. This would eliminate the need to store several full frames.

Frames using Temporal redundancy which predict information based on preceding frames are called “Inter-Frames” or Motion predicted Images.

Predictive & Motion Encoding

The next step in the MPEG process is termed “Predictive & Motion Encoding” and it takes advantage of both Spacial and Temporal redundancy to achieve compression.

I-Pictures

To begin the process of using Spacial and Temporal redundancy techniques in compression, we need a reference or a start frame which does not depend on previous or preceding frames.

This start frame would make use of Spacial redundancy within itself and is termed an I picture.

I pictures are Intra-Frames and have zero dependency on previous or preceding frames. They do however provide information to preceding frames.

The other pictures types used by MPEG are called P-Pictures (Predictive) and B-Pictures (Bi-Directional).

I Pictures carry the most amount of data content. They are 3 times the size of a P-Picture and 5 to 6 times the size of a B-Picture.

P-Pictures

The P-Pictures are Predictive Encoded Images also known as InterFrames.

As the name indicates, a P-Picture is a predicted Image based on previous I or P-Picture. The P-Picture is dependent on past Images to exist.

I or P

Picture

P-Picture

Predicted

by looking

back at

Information passed to generate P Picture

I or P Pic

B-Pictures

I or P

Picture

B-Pictures

Predicted

by looking

back at

I or P Pic

And

Future

P Picture

The B-Pictures have Bi-directional dependency and are called BiDirectional Predicted Images.

The B-Picture is also a predicted Image but it is based on prior I or P Pictures and preceding P-Pictures.

B-Pictures are typically made up of motion information and carry the least amount of data.

I, P and B picture generation process

Hoffman Encoding

To clearly understand the relationship between the I, P and B pictures we need to understand how they are generated.

1. The start of an entirely new scene would require an I-Picture or a reference for other pictures to follow until the next I-Picture.

- The information between the I-Picture and the next reference IPicture is called a GOP (Group of Pictures) which consist of one I and many P and B Pictures.

- I-Pictures typically re-occur at 15 picture intervals.

1. Next, the first P-Pictures in the GOP is generated based on the IPicture.

2. In between the I and first P-picture, several B-Pictures are generated as necessary to convey motion information from the I to the first P-Picture. For this reason B-Pictures are dependent on past and future pictures.

3. Then the process repeats with the generation of second P-Picture which is now based on the first P-picture. And so on…

Time

The last step in the MPEG process uses a statistical approach to compress the data further. The last process is called Hoffman Encoding. Basically, this process takes a look at the string of MPEG data and replaces it with information which allows regeneration. The best example is a string of eight “1’s” {11111111} replaced by {1x8} which represents; repeat the 1 eight times.

GOP

MPEG II –vs- MPEG I

The MPEG process described is common to both MPEG II and MPEG I thus, explaining the backward compatibility between the two.

The main differences between MPEG II and I are:

- MPEG II used in DVD uses a 720 x 480 resolution while MPEG I used in VIDEO CDs carries a resolution of 350 x 240. This difference alone accounts for a 75% reduction in data using MPEG I over MPEG II.

- MPEG II compresses data to about 1/40 on average while MPEG I compresses data to about 1/140 on average. Therefore 250Mbit/s are reduced to 6.25Mbits/s on average using MPEG II.

- MPEG II uses a variable rate compression while MPEG I uses a fixed rate.

350 x 240 = 84,000 pixels 720 x 480 = 350,000 pixels MPEG I represents 84,000/350,000 = 25% of MPEG II.

MPEG II additional information

MPEG II is a broad standard which encompasses many resolutions including HDTV. These variations in MPEG II are defined by Levels and Profiles.

DVD is just one of the many profiles and levels defined by MPEG II called Main Profile at Main Level ( MP@ML).

The Bit Rate Fluctuates

For DVD, variable bit rate is a tremendous advantage. If the bit rate were fixed, it could not accommodate the changing needs of video scenes. Consider the fast-paced action of a football player, running for a touchdown as the camera pans past the crowd. Full of motion, this is an extremely demanding scene, one that requires the bit rate to be very high. Now picture the same football player after the game, sitting in a restaurant, talking to his girlfriend. Almost nothing in the scene moves, so the bit rate can be quite low.

If DVD used a fixed bit rate, the system might fall short on the football scene. And it would definitely be wasting bits on the restaurant scene. DVD-Video accommodates both scenes by varying the bit rate. In fact, the maximum bit rate is 9.8 megabits per second which is nearly three times as high as the “average” rate.

If DVD used a fixed rate, it would have to be at least 7 Mbps to maintain picture quality! At that rate, total recording time would be cut in half. So the goal of capturing a full-length movie on a 3-3/4-inch disc could not be realized. V ariable bit rate is one of the key technologies that makes DVD possible.

By the way , V ideo CD uses MPEG-1 to yield a fixed bit rate of 1.15 Mbps. The fixed rate and low number translate into the vast quality difference between DVD-Video and Video CD.

24 Frames-per-Second Storage

In video, what appears to be a continuously moving image is actually a series of discrete still pictures, called frames. Every video frame consists of two interlaced “fields”, each of which contains half the frame’s scanning lines. A U.S.-standard video picture runs at roughly 30 frames per second. In contrast, movie file operates at 24 frames per second. So the movies you see on television, cable or videocassette have all had their frame rates converted by a special machine called a “telecine”.

The telecine converts the 24 film frames into video fields. However, video requires 30 frames or 60 fields and Film is 24. Telecine performs this process by converting 12 film frames to 24 fields (2 Fields/Film Frame) and another 12 film frames to 36 fields (3 Fields/Film Frame). It is kept seamless by converting one Film Frame to 2 Fields and the next one to 3. This cycle is repeated 2, 3, 2, 3 until the 60 fields have been completed. This Telecine process is called 2-3 Pull Down.

T o achieve maximum recording time, the DVD-V ideo disc is actually mastered in the original 24 film frame format. This reduces the video bit rate by 20%, even before MPEG-2 encoding. During playback, the DVD-Video player performs the 2-3 pull down function to generate a standard 30 frames per second video output.

NOTES

Model KW-34HD1 - Normal Operation

These are normal operating conditions for Sony’s first high Definition TV during power on/off and input selection conditions.

Operation Initial Step Sounds Visual Conditions Plug in AC connection Nothing Nothing Front panel Master power button off Power ONAMaster power ON

Power ONBPower ON in

TV OFF A TV OFF B

button press ed

remote pressed

Master Power OFF pressed Remote power OFF pressed

1. 2 Relays click imme diately

2. Degaussing c oil energized (humming sound)

3. TV audio 1 sec afte r relays click

1. 2 Relays click imme diately

2. Degaussing c oil energized (humming sound)

3. TV audio 1 sec afte r relays click

2 relays clicks TV sound mutes 2 relays clicks TV sound mutes

1. Front panel Standby light :

2. Blinking after relay click

3. Stops blinking in ab out 7 se c onds when the picture appears.

4. OSD: Yellow characters “Please check DTV receiver connections”

1. Front panel Standby light :

2. Standby light starts blinking afte r rel ay click

3. Stops blinking in 7 seconds when the picture appears.

4. OSD reads in Yellow characters “Please check DTV receiver connections”.

Picture goes dark All lights out Picture goes dark Standby light comes ON

AC connected. Set formerly OFF (by remote) .

1.3 Amps @120Vac

AC connected. Master power button ON Standby light ON TV OFF

1.3 Amps @120Vac

When this TV is ON there is no static electricity felt at the CRT screen. It is normal to have black left & right borders on both sides of the picture when viewing a 4:3 aspect ratio picture on a 16x9 aspect ratio TV picture tube.

TV Operation with NO Inputs connected

Selection Access Step Sounds Visual Conditions

Power ON

Video input Press TV/Video butt on

DVD, HD, input or High Definition TV input from external box VHF / UHF input Press the TV button on

Cable Input Pre ss the TV button on

until video 1, 2, or 3 appear on the screen Press TV/Vide o button until DVD or HD input is selected.

the remote

No sound when there is no video input.

No sound when there is no input.

Off the air white noise from the unconne cted VHF/UHF input. Off the air white noise from the unconne cted cable input.

Video 1, 2, or 3 appears in green letters at the upper left corner of the sc re en. Screen is dark with no video input.

DVD or HD appears in green letters at the upper left corner of the screen. Screen is dark with no input.

OSD station number appears in green at the upper right corner of the screen with snow. TV channels can be entered by remote or the up/down buttons will work if stations were p rogrammed during set up. OSD “C _” appears in green at the upper right corner of the screen with snow. Cable channels can be entered by remote or the up/down buttons will work if cable stations were programmed during set u p.

Power ON No inputs

Input Connections Programming Steps Results

Input Selection

VHF / UHF VHF / UHF antenna to rear panel “VHF /

UHF” F type connector.

Cable Connect cable feed to rear panel “Cable” F type

connector.

High DefinitionTVConnect an UHF antenna to the DTV Receiver

(external set-back box) and the rec eiver to the rear of the TV using the supplied mult i-pin I/O cable.

DVD, Video 13, or HD

Connect the vi deo and audio cables of the DVD, VCR, game, or camcorder to the rear panel phono jacks. The video 2 input is lo cated on the front panel. The HD box has component video (Y, R-Y, BY) outputs. They plug into the HD input (phono jacks ).

1. Power

ON.

2. Use the remote TV/Video button to select TV.

3. The remote ANT button toggles between VHF / UHF and cable. Sel ec t without a C prefix).

4. From the 4

Program: VHF / UHF

VHF / UHF

Menu icon, select & enter “

(channel number

Auto

”.

5. Use Channel Up/Dwn to change stations for norma l operation.

1. Power

ON.

2. Use the remote TV/Video button to select TV.

3. The remote ANT button toggles between VHF / UHF and letter “C”. Select a C prefix station like C4.

4. From the 4

. Cable station numbers are preceded with a

cable

Menu icon, selec t & enter

“Auto

Program: Cable”.

5. Use Channel Up/Dwn to change stations for norma l operation.

1. Power

2. Use the remote TV/Video button to s el ect

ON.

TV.

3. The remote ANT button toggles between VHF / UHF and cable. Sel ec t

4. From the 4

Program: VHF / UHF

VHF / UHF

Menu icon, select & enter “

(without a C prefix).

Auto

”. This tells th e s et-back box to auto program D TV stations too. (“ D T V A u to A dd” is only used to add DTV stations after one w as found.).

5. Use Channel Up/Dwn to change stations for HDTV reception.

1. Power

ON.

2. Use the remote TV/Video button to s el ect the desired input

1. See previous Power ON chart.

2. Snow or a TV station with a channel number will appear if you are corr ectly in the TV mode.

3. Correct VHF / UHF channels will be numbered 2-69. Cable channels are preceded with a letter C like C78.

4. It takes almost 1 m in . to scan through all the VHF / UHF stations. At the end it will select the lowest active VHF station.

1. See previous Power ON chart.

2. Snow or a TV station with a channel number will appear if you are corr ectly in the TV mode.

3. Correct Cable channels will be displayed as C1 to C125.

4. It takes about 1 min. to scan through all the cable stations. At the end it w ill select the lowest number active cable station.

1. See previous Power ON chart.

2. Snow or a TV station with a channel number will appear if you are corr ectly in the TV mode.

3. Correct VHF / UHF channels will be numbered 2-69. Cable channels are preceded with a letter C like C78.

4. It takes about 1 min. to scan through all the VHF/UHF stations. At the end it will select the lowest nu mber active statio n.

1. See previous Power ON chart.

2. The OSD will show the input selected as you press the T V /V ideo button. The input sequence is: Video 1-3, DVD, HD, TV and it repeats.

Inputs

RF Inputs

There are three independent RF inputs which allow the user to have cable, an outdoor antenna aimed for VHF and UHF stations and another antenna oriented for digital TV stations. Each RF input has a channel numbers assigned to it:

RF C hannel Num ber Assignm ent Input Channel Num bers Cable 1-125 VH F / UH F 2-13 / 14-69 DTV 1-99

They are selected from the ANT remote control button.

Composite Video

This is a single video 1, 2, or 3 input cable that carries the combined Y and C signal. The TV/Video remote control button selects it. This composite signal requires the receiver to first separate the two components, usually using a comb filter. The chroma is demodulated into individual color components, such as RGB, before the color information can be used. These additional processing steps reduce resolution and could add noise, but composite video is a convenient method of transporting a video signal.

PM3394, FLUKE & PHILIPS

ch1

ch2

ch3

CH1!5.00 V~

CH2!1.00 V~ L=121

CH3! 500mV= CHP MTB10.0us- 1.08dv ch1p

This scope shot is taken of a video signal that produces a blue screen. The top waveform is composite video and contains a combined signal. The middle waveform is the chroma signal from the S video output. It contains the burst after the retrace blanking area. The bottom waveform is the luminance signal containing the H sync pulse below the base line.

S Video Input

The S input refers to Separate Video inputs consisting of independent luminance (Y) and chroma (C) signals and a shield wire for each. They are input using a 5 pin standard connector. The fifth pin serves to close a switch in the jack that identifies the presence of the S video plug. The S Video signal is selected instead of the composite video 1-3 when the S video plug is detected.

The S video’s luminance signal is the picture’s brightness level signal. This Y input signal also carries both of the horizontal and vertical sync pulses. The chroma signal contains the color information phase referenced to the burst frequency of 3.58MHz. This C input contains 8 cycles of reference burst signal in the open retrace interval. The chroma signal requires demodulation into individual color components such as RGB before the color information can be used.

Component Video

Conversion

Video can be made of four components:

· Luminance or Y which defines the brightness level and

· Color, which is made of three components, called R-Y, B-Y and G-Y.

We can mathematically calculate the fourth component (G-Y) from the others so only three components are required for video:

Assuming R+B+G = Y, and (R-Y)+Y = R, then (G-Y) = -R-B. The manufacture of the G-Y signal can be performed in an electric matrix

consisting of summing op amps for adding (+) and subtractive op amps for the difference of the two signals (-). By adding the (inverted) signals, the last G-Y component can be derived.

DIGITAL

ANTENNA

VHF/UHF

(DTV)

SET-BACK

DOLBY DIGITAL

OUTPUT

(OPTICAL)

BOX

DTV I/O

FOR USE WITH

KW-34HD1

(DTV TV)

ONLY

ANALOG

INPUT

CABLE

VHF/UHF

L R

DVD

REAR PANEL

FOR USE WITH

HD (1080)

INPUT ONLY

DTV I/O

FOR USE WITH

KW-34HD1

(DTV RECEIVER)

S VIDEO

VIDEO

(MONO)

AUDIO

CONTROL S IN OUT

ONLY

AUDIO OUT

VAR/FIX

(MONO)

TV/VIDEO

RF (ANT)

VIDEO 1 VIDEO 2 VIDEO 3

DVD

INPUTS

ANT

- VHF AND SETBACK BOX HDTV

- CABLE

- VIDEO SETTINGS

- AUDIO SETTINGS

- VERTICAL SIZE AND CENTER

- CLOSED CAPTION/VERTICAL SHIFT/TILT

KW34HD1 REMOTE CONTROL

HDTV44

These simple matrixes are found in ICs frequently labeled as decoders or are part of a processor. A video processor IC can contain an additional simple electric matrix to convert the R-Y signals to their base Red signal voltages by just adding the Y signal as (R-Y) + Y = R. The RGB signals output can be used to drive the CRT.

R-Y resistor A R signal Y resistor B

Identification

Component video is usually carried on three lines: Y, R-Y, & B-Y. They can also abbreviated differently, but are the same:

· Y, U, V

· Y, Cr, Cb

· Y, Pr, Pb

· Y, R-Y, & B-Y.

The Y, Pr, Pb version designates the progressive instead of interlaced picture scan format. This TV selects the DVD or HD component video input from the TV/Video remote button. However, the HD signal must have a horizontal frequency of 31 to 34kHz or the screen will remain dark with just an “HD” OSD.

Waveforms

The following is a scope shot of component video signals that makes up a blue screen picture. In the top waveform is the Y signal. It houses the horizontal sync pulses (the vertical is not seen at this time base, but it is present in the Y signal). The line between the sync pulses represents the brightness level. The higher the line, the brighter the picture. Therefore, a voltage at the sync pulse level is black.

PM3394, FLUKE & PHILIPS

ch1

ch2

ch3

Channel 1 Y DV D output 7.5Vp-p Channel 2 B-Y DV D output 5Vp-p Channel 3 R-Y D VD output 1Vp-p Tim e base 10usec/div

For comparison, the following component video waveforms are of a picture on a blue screen. The Y signal contains voltages of various brightness levels centered on the screen between the H. sync pulses. The B-Y and R-Y signals contain changing color levels in the middle of the screen. Note that by looking at either color signal without the Y signal level, it is not possible to know where the sync area is. It is therefore difficult for your scope to sync on the R-Y or B-Y signal alone without a reference.

ch1

ch2

ch3

CH1!5.00 V~

CH2!5.00 V~ L=121

CH3!5.00 V= CHP MTB10.0us- 1.08dv ch1p

Blue screen – waveform Y UV

Nam e Location Voltage/div

PM3394, FLUKE & PHILIPS

The middle waveform is the B-Y signal. The area corresponding to the horizontal sync pulse in the Y signal is at 0Vdc. The remainder of the voltage minus the Y level is the Blue color level. Since this is a picture of a blue screen, the voltage is high.

The bottom waveform is the R-Y signal. The area corresponding to the horizontal sync pulse in the Y signal is also at 0Vdc. The red - Y level during a blue screen is below 0Vdc. It will be equal to 0Vdc if the Y signal is subtracted.

CH1!10.0 V~

CH2!5.00 V~ L=121

CH3!5.00 V= CHP MTB10.0us- 1.08dv ch1p

Picture centered on Blue screen – waveform Y sig

Nam e Locatio n Voltage/div Channel 1 Y DV D output 7.5Vp-p Channel 2 B-Y DV D output 5Vp-p Channel 3 R-Y D VD output 1Vp-p Tim e base 10usec/div

DIGITAL

ANTENNA

VHF/UHF

(DTV)

SET-BACK

DOLBY DIGITAL

OUTPUT

(OPTICAL)

BOX

DTV I/O

FOR USE WITH

KW-34HD1

(DTV TV)

ONLY

ANALOG

INPUT

CABLE

VHF/UHF

L R

DVD

REAR PANEL

FOR USE WITH

HD (1080)

INPUT ONLY

DTV I/O

FOR USE WITH

KW-34HD1

(DTV RECEIVER)

S VIDEO

VIDEO

(MONO)

AUDIO

CONTROL S IN OUT

ONLY

AUDIO OUT

VAR/FIX

(MONO)

TV/VIDEO

RF (ANT)

VIDEO 1 VIDEO 2 VIDEO 3

DVD

INPUTS

ANT

- VHF AND SETBACK BOX HDTV

- CABLE

- VIDEO SETTINGS

- AUDIO SETTINGS

- VERTICAL SIZE AND CENTER

- CLOSED CAPTION/VERTICAL SHIFT/TILT

KW34HD1 REMOTE CONTROL

HDTV44

Overall Block

There are three main sections in Sony’s model KW34HD1 first generation High Definition T elevision (HDTV):

1. Video Processing

2. Deflection

3. Power Supply The additional circuit blocks in each section and the external box needed to receive the off the air UHF, HDTV signals distinguish this High Definition TV from a conventional TV .

Video Processing

Because no one HDTV standard has been determined, this first generation HDTV has the flexibility to accept any of the following inputs:

Sony m odel KW 34H D1 inputs

Input B lock Location Signal form at VH F/UH F antenna Digital channels 1-99 VH F/UH F antenna Analog channels 2-69 Cable Channels 1-125 Video 1 – 3 Phono jacks DVD Phono jacks HD Phono jacks

The signal path for these inputs is shown below:

Digital Input

VHF/UHF antenna HDTV Box (accepts all 18 DTV formats) Video Processor

Þ DTV Sw (twin view or SD picture)

ß MID (stores both twin pictures)

RGB Driver Sel (selects twin pix path) CRT cathode Video processor

HD TV external box RF

Main & Sub Tuners via antenna switch

Video Selector Sw C om posite video;

DVD Switch Y, Pb, Pr

Video Processor Y, Pb, Pr

L & R channel audio.

L & R channel audio

Þ RGB Driver Þ CRT

VHF/UHF /Cable Analog Reception

Air or cable selection by the Main Micro is performed at the input antenna switch (SW). Thereafter the signal path is the same.

VHF/UHF antenna or cable Input antenna switch (SW) Main/sub tuners Video selector DVD switch DTV switch DRC SEL Video processor RGB Driver CRT cathodes

Video Inputs 1 – 3

Composite video from a VCR or satellite (DSB) receiver Video selector DVD switch DTV switch DRC SEL Video processor RGB Driver CRT cathodes

DVD Input

DVD switch DTV switch DRC SEL

Video processor RGB Driver CRT cathodes

HD Input

This input is for an external HDTV (perhaps cable) box that receives and decodes the HDTV to output component video: Y, R-Y , B-Y (also called Y, Pb, Pr or Y , Cb, Cr , or Y, U, V , depending upon where you are in the world). The component video path introduces the component video directly into the video processor block. The scan width of this picture is a function of the horizontal frequency .

Video processor RGB Driver CRT cathodes

Deflection

The deflection control IC develops signals for:

= Vertical and horizontal deflection (VD & HD) = Horizontal pincushion (EW) = Picture tilt & horizontal trapezoid correction (VD) = Focus (V blk)

Vertical and horizontal deflection

The vertical stage is conventional, but the horizontal stage is not. Both the horizontal driver and output stages have individual PWM stages that supply regulated B+ voltage to them. The H. output B+ comes from the PWM stage through the flyback.

Horizontal Pincushion

The horizontal pincushion correction stage compensates for a picture that is bent inward at the middle of the screen. The E/W correction signal from the deflection controller is amplified and applied to the yoke at the horizontal output transistor’s collector to correct for insufficient scan.

Picture tilt and horizontal trapezoid correction

Vertical drive (VD) signals not only feed the vertical deflection stage, but also the picture tilt stage that handles trapezoid correction. A controlled level of vertical sawtooth (VD) signal is used for trapezoid correction. This correction signal is mixed with a DC voltage for tilt correction and applied to the N/S coil suspended about the bell of the picture tube by the yoke.

Focus

There are two focus circuits used in this TV. The dynamic focus circuit uses horizontal pulses to correct the left and right side picture focus caused by the flat screen. The dynamic correction voltage is added into the static (DC) focus voltage that is applied to the picture tube.

The quad focus circuit uses both H & V signals to correct spot shape at the four corners of the screen. The circuit’s correction voltage is output to four “QP” coils mounted on a board surrounding the picture tube’s electron gun.

Power Supply

The power supply consists of:

= A small 60Hz standby power supply that supplies standby +5V to the

Main Micro.

= A Main Micro IC that controls the power relay as well as the deflection,

video, and audio stages.

= A degaussing circuit. = Two almost identical converter stages. Converter 2 turns on converter

1. Different voltages are output from each converter to power the TV .

= A protection circuit to detect excessive voltage and excessive current

in various parts of the TV. The protect circuit also monitors vertical drive. A failure in the detected areas causes the power ON command to be removed from AC relay .

Video Block 1

Input Formats

This direct view 34” model KW34HD1 High Definition TV can accept various formats and present them in a single or double Twin View To perform this, each input signal must be processed into a common format, then selected for viewing. The inputs are:

Sony M odel KW 34HD 1 Inputs

Input Format Processing

NT SC analog VHF/U HF channels 2-69

Cable (analog) channels 1-125

Video 1 – 3 Com posite video

DV D Com ponent

HD Sam e as above C om ponent video into R G B

RF Dem odulation into video.

Video into Y & C . Y & C into com ponent video (Y,

C b , C r .) Com ponent video into R GB

RF Sam e as above except different

L & R audio

video L & R audio

RF frequencies are received. Video into Y & C . Y & C into com ponent video (Y,

C b , C r .) Com ponent video into R GB Com ponent video into R GB .

Ò picture.

The main and sub (Y & C) outputs run parallel paths through similar ICs before leaving the A board. The main and sub signals are converted to component video in Chroma Decoders IC2403 (sub path) and IC2404 (main path). The Y, R-y, B-Y signals are applied to switches IC2405 and IC2406 to enable DVD input selection.

DVD Input

Switches IC2405 and IC2406 can now select between the processed composite video signal and the rear panel DVD input. The DVD signal must also be applied to the sub input line so that it can appear as the second or sub picture in the Twin V iew mode. Whatever is input on the main picture path is duplicated in the sub path. Switch selection is performed using serial data from the Main Micro IC3251 (not shown). The switched signal is applied to the next switch in both signal paths.

DTV Input

Switches IC2407 and IC2408 introduce the digital TV from the external setback box. This DTV signal path is used when:

· Viewing the HD or SD Digital TV signal as a sub picture (Twin View mode); or

· The DTV signal is of standard definition (525 lines/480 lines viewable) and line doubling is required.

When viewing just the single HDTV picture, the DTV signal is applied directly into the video processor IC3005 (Video Block 3) and does not come this way (except during Twin V iew).

Signal Flow

RF Input

The RF signals input to the main and sub tuners are channel selected and RF demodulated into composite video. The composite video from the tuner is applied to the video Switch IC2006 along with composite videos 13 from the rear and front panel for user selection.

Video Inputs

Video Switch IC2006 selects the video for the main and sub pictures. It also sends the video through comb filters. The comb filters separate the composite video into their luminance (Y) and chroma (C) parts.

A Board Output

The main and sub picture paths leave the A board and are passed through the G board into the digital processing stages on the V board. This signal routing through the G board is necessary because both the vertical A and V boards plug into the horizontal G board.

Ò Sony , Trinitron, and Twin View are registered trademarks of Sony.

Video Process A

The external video input from the rear panel and internal video from both main and sub tuners is applied to this stage for selection and conversion to (Y, R-y, B-y) component video. The major parts in this early video processing are listed below:

Major Video Processing Components Shown Name Input Output Purpose Video Switch

IC2006

Buffers Q2016, Q2420, Q2422.

YUV Switch ½ IC2406

Buffers Q2015, Q2421

2 tuners, 3 video inputs Y & C from 2

comb filters 1Vp-p of Y from

IC2006/pin 35 1Vp-p of Y at

IC2406/pin 28 1Vp-p of C

from IC2006/pin 31

Main Y & C Sub Y & C

(similar processing not shown)

1Vp-p of Y to IC2406/pin 28

2Vp-p at pin 22 6db amp

1Vp-p of C to IC2404/pin 32

Selects composite video

Routes to comb filter

Y buffers

C buffers

Video Switch

Five composite video inputs are applied to video switch IC2006. Serial data from Main Micro IC3251 (not shown) chooses which input signals take the main and sub picture signal paths. The chosen signals go to their respective comb filters. The 3D filter is always kept in the main picture path and the glass filter (FL2001) is used in the sub picture path.

The Y & C outputs from both comb filters are returned to IC2006 and output again. The main picture path is from pins 31 and 35. The sub video path is from switch IC2006/pins 25 and 30 and runs a parallel route to the main one (Video Block 1) for identical processing.

Component Video

Then the Y signal is input the Chroma Decoder. The chroma (C) signal is also buffered and input to Chroma Decoder IC2404/pin 32. IC2404 uses both the Y & C inputs for level conversion to Y, Cr, Cb (component video).

Chroma Decoder IC2404

All signal levels were taken using a color bar input.

Main Y & C at pins 34 and 32

Y=2Vp-p, C=1Vp-p

Y = 1Vp-p; Cr, Cb = 0.5Vp-

p @ pins 18-20

Changes Y/C to component video

Video Process B

Signal Flow

Input Selection

Main component video from the Chroma Decoder IC2406 is only one input into switch IC2406. The second input to IC2406 is DVD component video from the rear panel phono jacks.

The Main Micro IC3251/pin 78 and 79 sends logic level voltages into IC2406/ pins 25 and 4/27 for the input selection. The chart shows the switching voltages for selecting an input:

IC2406 Selection

Input selected IC2406/pin 25 I C2406/pins 4, 27 M ain (RF, video) L H DVD H L

Closed Caption

The luminance passes through switch IC2406, which adds closed caption or XDS station information as an OSD. If the user requests this feature, this caption information enters IC2406 as an RGB signal from IC2409. The take off or input signal for the closed caption decoder IC2409 is at the output of this YUV switch at IC2406/pin 22.

DTV Selection

Switch IC2407 chooses between the main and DTV signal for the main picture path. The DTV signal is chosen only when:

· Viewing the HD or SD Digital TV signal as a sub picture (Twin View mode) or

· The DTV signal is of standard definition (525 lines/480 lines viewable) and line doubling is required.

The DTV path is chosen when IC2407/pin 9-1 1 is low:

IC2407 Selection

Input selected Sw signal IC2407/pin 9, 10, 11 M ain (RF, video) H DTV L

The output of the DTV/Main switch IC2407 is buffered and sent through the G board to the V board for digital processing.

Filtering

When high frequency analog signals are sent into a digital stage, the high frequency component can create a secondary signal. This second signal is called an alias component. Alias signals are eliminated by low pass filtering (LPF) the analog input. That is the purpose of the filter networks at the output of IC2406.

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